JP2009011581A - Ultrasound diagnosis apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a method of calculating the displacement amount of an object tissue surface. <P>SOLUTION: A displacement amount detection part 50 calculates the displacement amount for each region on the object tissue surface on the basis of two or more pieces of voxel data gathered for each time phase. A displacement amount smoothing part 80 calculates the displacement amount after smoothing processing for each region by applying the smoothing processing to the displacement amount of each region calculated in the displacement amount detection part 50 utilizing the displacement amount of a vicinity region present near the region. A coloring processing part 56 forms three-dimensional displacement image data by executing coloring processing corresponding to the displacement amount after the smoothing processing of the region to pixel data corresponding to each region on the surface of the object tissue within three-dimensional image data formed for each time phase on the basis of the two or more pieces of voxel data. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to a three-dimensional ultrasonic diagnostic apparatus for diagnosing the motion of a target tissue.

  An ultrasonic diagnostic apparatus is used for diagnosing abnormal motion of a target tissue, for example, abnormal motion in the expansion / contraction motion of the heart. In order to diagnose abnormal motion of the target tissue, it is desirable to use an ultrasonic diagnostic apparatus that can accurately diagnose the motion of the target tissue.

  On the other hand, with the advancement of ultrasonic technology, diagnosis using a three-dimensional ultrasonic diagnostic apparatus that can three-dimensionally express a target tissue in a three-dimensional space has become a reality. The superiority of the three-dimensional ultrasonic diagnostic apparatus is also remarkable in, for example, cardiac ultrasonic diagnosis. In other words, by observing the expansion / contraction motion of the heart using a three-dimensional ultrasonic diagnostic apparatus, it is possible to perform a diagnosis based on a three-dimensional shape grasp that is difficult with a two-dimensional ultrasonic diagnostic apparatus.

  Under such circumstances, Patent Document 1 proposes an epoch-making technique that realizes a display method capable of visually grasping the displacement of a target tissue in a three-dimensional ultrasonic diagnostic apparatus. According to the technique described in Patent Document 1, by performing a coloring process based on the amount of displacement on the surface of a target tissue such as the heart, it is possible to accurately diagnose abnormal movement or abnormality occurrence position of the target tissue. Is possible.

JP 2004-195082 A

  The inventor of the present application has conducted research and development on an epoch-making improvement in the technique described in Patent Document 1. In particular, studies have been made on methods for calculating the amount of displacement of the target tissue surface.

  The present invention has been made in the course of research and development, and an object thereof is to improve a method for calculating the amount of displacement of the target tissue surface.

  In order to achieve the above object, an ultrasonic diagnostic apparatus according to a preferred embodiment of the present invention collects a plurality of voxel data for each time phase from within a three-dimensional space including a target tissue by transmitting and receiving ultrasonic waves. Transmission / reception means, displacement amount calculating means for calculating a displacement amount for each part on the target tissue surface based on a plurality of voxel data collected for each time phase, and each part calculated by the displacement amount calculating means Smoothing means for calculating the amount of displacement after smoothing for each part by applying a smoothing process to the amount of displacement of the part using the amount of displacement of the neighboring part existing in the vicinity of the part; In the three-dimensional image data formed for each time phase based on the voxel data, the pixel data corresponding to each part on the surface of the target tissue is displayed according to the displacement amount after smoothing the part. Processing More, and having a displacement image forming means for forming a three-dimensional displacement image data, and display image forming means for forming a display image based on the three-dimensional displacement image data.

  According to the above aspect, since the smoothing process is performed on the displacement amount, the result of the display process corresponding to the displacement amount is relatively smooth. For example, when the coloring process is performed as the display process, a smooth coloring display can be obtained.

  In a desirable mode, the smoothing means calculates an average value of the displacement amount of each part calculated by the displacement amount calculating means and the displacement amount of at least one neighboring part on the target tissue surface adjacent to the part, The calculated average value is used as a displacement amount after the smoothing process of the part.

  In a preferred aspect, the displacement amount calculation means includes a reference point and a target tissue set based on a structure of a target tissue in a three-dimensional data space constituted by a plurality of voxel data collected from the three-dimensional space. The amount of displacement is calculated for each part by tracking the movement of each part along a straight line connecting each part on the surface.

  In a preferred aspect, the displacement amount calculation means is configured to calculate the position based on the spatial distance between two voxel data of different phases corresponding to the position existing on or near the straight line connecting the reference point and each position. The amount of displacement is calculated.

  In a desirable mode, the displacement image forming means performs a coloring process according to a displacement amount after the smoothing process of each part as the display process.

  According to the present invention, the method for calculating the displacement amount of the target tissue surface is improved. For example, according to a preferred aspect of the present invention, since the smoothing process is performed on the displacement amount, the result of the display process corresponding to the displacement amount becomes relatively smooth.

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

  FIG. 1 shows a preferred embodiment of an ultrasonic diagnostic apparatus according to the present invention, and FIG. 1 is a functional block diagram showing the overall configuration thereof. The ultrasonic diagnostic apparatus of the present embodiment is suitable for visually expressing the motion of the target tissue. The target tissue is an organ that accompanies exercise, and the ultrasonic diagnostic apparatus of the present embodiment is suitable for diagnosing, for example, the contraction and expansion motion of the heart. Therefore, the function of the ultrasonic diagnostic apparatus according to the present embodiment will be described below with the heart as the target tissue.

  The transmission / reception unit 12 transmits / receives an ultrasonic wave via the probe 10 in a space including the left ventricle as a target tissue. Then, a plurality of echo data in the three-dimensional space including the left ventricle is acquired for each time phase volume and stored in the three-dimensional data memory 14. The inversion binarization processing unit 16 performs inversion processing and binarization processing on the echo value of the echo data of each voxel stored in the three-dimensional data memory 14. That is, a voxel corresponding to the heart chamber in the left ventricle having a relatively small echo value is set as a voxel having a high luminance value, and a voxel corresponding to another portion having a relatively large echo value is set as a voxel having a low luminance value.

  Each voxel having two kinds of high and low luminance values subjected to the inverse binarization processing is mainly intended to remove high-frequency noise components in the noise removal unit 18, the smoothing processing unit 20, the line correlation unit 22, and the frame correlation unit 24. The processed image processing is executed.

  The noise removing unit 18 determines voxels having different luminance values that are spatially isolated as noise and converts the luminance values. For example, when the luminance value of the target voxel and the luminance values of all 26 surrounding voxels spatially adjacent to the target voxel are different, the target voxel having a different luminance value is converted into the same luminance value as that of the surrounding voxels. The smoothing processing unit 20 calculates the average value of the luminance values of the target voxel and the surrounding 26 voxels adjacent to the voxel with respect to the luminance value of each voxel output from the noise removing unit 18, and calculates the calculation result. The brightness value of the target voxel is newly set.

  The line correlator 22 performs an averaging process between the lines in a two-dimensional frame constituting a certain time phase volume on the luminance value of each voxel output from the smoothing processor 20. In addition, the frame correlation unit 24 performs an averaging process between the two-dimensional frames constituting the volume of a certain time phase on the luminance value of each voxel. Each voxel converted into various luminance values in the smoothing processing unit 20, the line correlation unit 22, and the frame correlation unit 24 is output to the coordinate conversion unit 26. The coordinate conversion unit 26 converts the coordinate value of each voxel from the R, θ, φ coordinate system based on the probe to the X, Y, Z coordinate system based on the cube.

  The binarization circuit 30 is composed of a comparator and the like, binarizes an ultrasonic image composed of various luminance values output from the coordinate conversion unit 26 based on a predetermined threshold value, and performs a heart chamber in the left ventricle. A binarized image composed of two types of voxels, that is, a voxel corresponding to a portion and a voxel corresponding to another portion, is formed and output to the edge detecting means 34 and the center of gravity detecting portion 36.

  The edge detection unit 34 performs surface extraction processing of the left indoor wall from the binarized image output from the binarization circuit 30. Here, the edge detection means 34 is demonstrated using FIG.

  FIG. 2 is a block diagram showing the internal configuration of the edge detection means. The edge detection means 34 includes two frame memories (1) and (2), six line memories (1) to (6), a voxel data memory 70, and a surface extraction processing unit 72. The output of the binarization circuit 30 is output as a voxel data string in the order adjacent to each other on the image in units of echo values (voxel data) of voxels constituting each time phase volume. That is, the voxel data string that forms a volume has the voxel data arranged in the order from the first frame to the last frame that constitutes the volume, and in the order from the first line to the last line that constitutes the frame in the frame. It is out.

  The frame memory is a memory that outputs a voxel data string after storing it in frame units, and functions as a delay buffer for one frame. The line memory is a memory that outputs a voxel data string after storing it in line units, and functions as a delay buffer for one line. That is, the output of the frame memory (1) is voxel data one frame before the voxel data output from the binarization circuit 30, and the output of the frame memory (2) is output from the binarization circuit 30. It becomes voxel data two frames before the voxel data. In this way, the voxel data memory 70 receives the voxel data of the current frame, one frame before, and two frames before.

  Further, the output of the line memory (1) is voxel data one line before the voxel data output from the binarization circuit 30, and the output of the line memory (2) is output from the binarization circuit 30. It becomes voxel data two lines before the voxel data. The output of the line memory (3) is voxel data one line before the voxel data output from the frame memory (1), and the output of the line memory (4) is voxel data output from the frame memory (1). Voxel data two lines before. The output of the line memory (5) is voxel data one line before the voxel data output from the frame memory (2), and the output of the line memory (6) is voxel data output from the frame memory (2). Voxel data two lines before. In this way, the voxel data memory 70 is input with a total of 9 lines of voxel data of 3 adjacent lines in the current frame, 3 lines before 1 frame, and 3 lines before 2 frames. .

  The voxel data memory 70 has 27 latches, three for each of the nine lines. Three latches corresponding to each line extract three consecutive voxel data on the line.

  As described above, the voxel data output from the latch (14) is set as a target voxel, and 27 voxel data groups obtained by adding 26 adjacent voxel data to the periphery are output to the surface extraction processing unit 72. .

  The surface extraction processing unit 72 has voxel data corresponding to the heart cavity portion as the data of the target voxel, and one of the 26 voxel data adjacent to the periphery of the target voxel data corresponds to other regions. If data exists, this target voxel is determined as a surface voxel of the heart chamber. By making this determination with all voxels in each time phase volume as the target voxel, a group of voxels forming the surface of the heart chamber in each volume, that is, a heart chamber surface image (an outline image of the ventricular wall). can get. The heart cavity surface image formed for each volume is output to the end diastole edge memory (reference numeral 38 in FIG. 1) or the like.

  Returning to FIG. 1, the end diastole edge memory 38 stores the heart chamber surface image at the end diastole time point of the ventricle from the heart chamber surface images at each time phase output from the edge detection means 34. An R wave of an electrocardiographic waveform is input to the end diastole edge memory 38, and the end diastole time point is determined based on the R wave generated at the end diastole time point of the ventricle. The front edge memory 40 is a memory that temporarily stores the cardiac cavity surface image in each time phase output from the edge detection means 34 for each time phase. The selector 42 selects either one of the heart chamber surface image at the end diastole output from the end diastole edge memory 38 and the heart chamber surface image of the past time phase output from the front edge memory 40. And output to the displacement amount detection unit 50. The selection operation by the selector 42 is based on an instruction from the user.

  The binarized image output from the binarization circuit 30 is also input to the centroid detection unit 36, and the centroid detection unit 36 calculates the centroid point coordinates of the heart cavity based on the binarized image. In some cases, the image of the heart chamber does not have a completely closed outer surface. In this case, the calculation of the barycentric point may be performed on the region of interest set in advance so as to surround the heart chamber. The end diastole center point memory 44 stores the center point coordinates of the heart chamber at the end diastole of the ventricle. The R wave of the electrocardiogram waveform is input to the end diastole center-of-gravity point memory 44, and the end diastole time point is determined based on the R wave generated at the end diastole time point of the ventricle.

  The displacement amount detection unit 50 detects a displacement amount between time phases for each part in the heart cavity surface. In the displacement amount detection unit 50, either the cardiac chamber surface image at the end diastole output from the end diastole edge memory 38 or the heart chamber surface image of the past time phase output from the front edge memory 40. One is input via the selector 42. Further, the displacement amount detection unit 50 also receives the current heart chamber surface image output from the edge detection means 34 and stores the center point of the heart chamber at the end diastole stored in the end diastole center point memory 44. Coordinates are also entered. The displacement amount detection unit 50 detects the displacement amount based on the input information. Therefore, a displacement amount detection method by the displacement amount detection unit 50 will be described with reference to FIG.

  FIG. 3 is a diagram for explaining a displacement amount detection method in the present embodiment. FIG. 3A shows a data space constituted by a plurality of echo data (voxel data) collected from a three-dimensional space including the left ventricle of the heart. Although the data space in this embodiment is a three-dimensional data space, in FIG. 3A, the data space is expressed in a two-dimensionally simplified manner by an xy coordinate system. And each voxel data exists in the position of the vertex of the some grid | lattice-like grid shown with a broken line. In addition, when the data space is expressed three-dimensionally, a z-axis that is orthogonal to both the x-axis and the y-axis may be added.

  In FIG. 3A, the current position of the heart chamber surface (surface position B in the current phase) and the position of the heart chamber surface before the current one phase (surface position C in the previous time phase) are xy. It is shown two-dimensionally in the coordinate system. Further, the reference point A indicates the center-of-gravity point coordinates of the heart cavity. The surface position B of the current time phase is based on the heart chamber surface image of the latest time phase output from the edge detection means (reference numeral 34 in FIG. 1). This is based on the surface image of the heart chamber before one time phase obtained from the selector 40 (reference numeral 42 in FIG. 1) from the reference numeral 40). The reference point A is based on the barycentric coordinates of the heart chamber at the end diastole obtained from the end diastole barycentric point memory (reference numeral 44 in FIG. 1).

  When detecting the displacement amount of the surface of the heart cavity, first, a straight line connecting each of a plurality of parts on the surface position B of the current phase and the reference point A is set. That is, in FIG. 3A, a plurality of straight lines connecting each of the plurality of black circle points indicated at the surface position B and the reference point A are set. In the three-dimensional data space, since the surface of the heart cavity exists so as to surround the reference point A that is the center of gravity, a plurality of straight lines are set radially from the reference point A toward the surface of the heart cavity.

  When a plurality of straight lines are set, the surface position C of the previous time phase is searched at equal distances from the reference point A along each straight line. For example, as shown in FIG. 3A, voxel data existing in the vicinity of the position (for example, the closest position) is confirmed at each position intersecting with the arcs of a plurality of two-dot chain lines on each straight line. The search ends when the neighboring voxel data is the voxel data of the surface position C of the previous time phase. In this way, each of the plurality of black circle points indicated at the surface position C in FIG.

  In FIG. 3A, among the plurality of black circle points at the surface position B and the surface position C, the corresponding black circle points are shown connected by arrows. Thus, the length of the arrow (distance between the surfaces) detected for each straight line becomes the displacement amount of each part between the previous time phase and the current time phase.

  FIG. 3B shows the displacement amount of each part detected by the method described with reference to FIG. That is, FIG. 3B shows the inter-surface distance (displacement amount between the previous time phase and the current time phase) for each of the parts (parts 1 to 8) along the y-axis direction. Yes.

  In FIG. 3, the current position of the surface of the heart cavity (surface position B of the current phase) and the position of the surface of the heart cavity before the current time phase (surface position C of the previous time phase). The amount of displacement of each part is detected, but this detection process is executed for each time phase as the time phase advances. That is, as the time phase advances, the displacement amount of each part is detected for each time phase while updating the surface position B of the current time phase and the surface position C of the previous time phase. In addition, instead of the current position of the heart chamber surface one time before (surface position C of the previous time phase), the end diastole edge memory (reference numeral 38 in FIG. 1) is passed through a selector (reference numeral 42 in FIG. 1). The displacement amount of each part may be detected from a comparison between the heart chamber surface at the end diastole obtained and the current heart chamber surface.

  Returning to FIG. 1, when the displacement amount detection unit 50 detects the displacement amount of each part within the surface of the heart chamber, the detected displacement amount of each part is stored in the displacement amount memory 52. The displacement amount (displacement amount data) stored in the displacement amount memory 52 is smoothed in the displacement amount smoothing unit 80 and then stored in the displacement amount memory 53.

  The color determination means 54 determines a color based on the amount of displacement of each part in the heart cavity surface. That is, the displacement amount of the surface portion to be colored is read from the displacement amount memory 53, and for example, a color predetermined for each displacement amount is set as the color of the portion. Then, the coloring processing unit 56 performs a coloring process on the current heart cavity surface image output from the edge detection unit 34 by the color of each part of the surface determined by the color determination unit 54, and the image composition unit 58. Output to.

  The image synthesizing unit 58 synthesizes a three-dimensional displacement image obtained by synthesizing the three-dimensional image including the heart cavity part output as it is from the coordinate conversion unit 26 and the colored heart cavity part surface image output from the coloring processing part 56. Form.

  The display image forming unit 60 forms a two-dimensional display image obtained by projecting the three-dimensional displacement image on a plane. When projecting a three-dimensional image onto a plane, the display image forming unit 60 may perform a rendering operation based on the volume rendering method to form a two-dimensional display image that is transparently displayed inside the target tissue. The rendering calculation based on the volume rendering method is preferably, for example, the method disclosed in JP-A-10-33538. The method described in the above publication is as follows.

  A plurality of rays (for example, coincident with the ultrasonic beam) are set for the three-dimensional space. Echo values are referred to in turn for each ray, and rendering operations are sequentially executed for each echo value. In parallel with this, accumulation of each opacity (opacity) is performed, and when this value becomes 1 or more, the rendering operation for the ray is finished. A rendering calculation result at this time is determined as a two-dimensional display pixel value corresponding to the ray. By determining the pixel value for each ray, a two-dimensional display image in which the inside of the target tissue is transparently displayed as a set is formed.

  In this way, the two-dimensional display image formed by the display image forming unit 60 is displayed on the display 62. An example of a two-dimensional display image obtained by projecting a three-dimensional displacement image on a plane is shown in FIG. 6 described later.

  As described above, in this embodiment, a three-dimensional displacement image is formed by applying a coloring process according to the amount of displacement of each part on the surface of the heart cavity part. At that time, the displacement amount smoothing unit 80 applies a smoothing process to the displacement amount of each part. Therefore, the smoothing process for the displacement amount will be described.

  FIG. 4 is a diagram for explaining the smoothing process for the displacement amount. FIG. 4A shows the inter-surface distance (displacement amount) of each part before the smoothing process. FIG. 4A shows the graph of FIG. 3B in a landscape orientation. In the state before the smoothing process shown in FIG. 4A, the displacement amount of each part has only three stages. That is, the displacement amount of the region 1 and the region 2 is the same size, the displacement amount from the region 3 to the region 5 is the same size, the displacement amount from the region 6 to the region 8 is the same size, Between part 1 to part 8, there are only three different amounts of displacement.

  Therefore, when the coloring process is performed according to the amount of displacement before the smoothing process shown in FIG. 4A, the color change between the part 1 and the part 8 becomes a low gradation with only three stages. Further, since the same color is assigned to the part 1 and the part 2, the same color is assigned to the part 3 to the part 5, and the same color is assigned to the part 6 to the part 8, the distance resolution becomes low. Give the impression.

  Therefore, in the present embodiment, the smoothing process is performed using the displacement amount of the nearby region with respect to the displacement amount of each region. For example, for the part 1 before the smoothing process shown in FIG. 4A, the average value of the displacement amounts of the part 1 and the part 2 is calculated using the displacement amount of the adjacent part 2, and the average value is smoothed. It is set as the displacement amount of the site | part 1 after a process. Further, for the part 2 before the smoothing process shown in FIG. 4A, the average value of the displacements of the part 1, the part 2 and the part 3 is calculated using the displacements of the adjacent part 1 and part 3; The average value is set as the displacement amount of the part 2 after the smoothing process.

  FIG. 4B shows the result of the smoothing process performed on the displacement amounts from the part 1 to the part 8 shown in FIG. Further, in FIG. 4C, the change in the displacement amount of each part before the smoothing process and the change in the displacement amount of each part after the smoothing process are displayed in an overlapping manner. In FIG. 4C, the solid line is the change in the displacement amount before the smoothing process, and the broken line is the change in the displacement amount after the smoothing process.

  As shown in FIG. 4A to FIG. 4C, the change in the displacement amount is only three steps before the smoothing process, whereas from the part 1 to the part 7 after the smoothing process. The amount of displacement changes for each part. Therefore, by applying the coloring process to each part according to the displacement amount after the smoothing process, the color change increases to 7 gradations, and the smooth coloring process can be performed.

  In the present embodiment, the displacement amount smoothing unit 80 in FIG. 1 performs a third-order smoothing process on the displacement amount of each part. Therefore, a specific smoothing process in the displacement amount smoothing unit 80 will be described.

  FIG. 5 is a functional block diagram for explaining the internal configuration of the displacement amount smoothing unit (reference numeral 80 in FIG. 1). The neighborhood data acquisition unit 81 reads out displacement amount data of all the parts (all voxels) stored in the displacement amount memory 52 in a stepwise manner. At that time, the neighborhood data acquisition unit 81 corresponds to the displacement amount data corresponding to the site of interest (target voxel) and 26 neighborhood voxels adjacent to the site of interest so as to surround the site of interest for each stage. The displacement amount data is read from the displacement amount memory 52 and output to the subsequent units.

  The addition processing unit 82 adds displacement amount data relating to a total of 27 voxels of the target voxel and 26 neighboring voxels adjacent to the target voxel. The valid data counting unit 85 counts the number of valid data whose displacement amount is not zero among the displacement amount data regarding a total of 27 voxels of the target voxel and 26 neighboring voxels adjacent to the target voxel. Then, the division processing unit 83 calculates the average value of the displacement amounts by dividing the added value of the displacement amount data by the number of valid data.

  The attention data determination unit 86 determines whether or not the displacement amount regarding the attention voxel is zero, and controls the gate processing unit 84. If the displacement amount of the target voxel is not zero, the gate processing unit 84 stores the average displacement amount obtained by the division processing unit 83 in the displacement amount memory 53. On the other hand, when the displacement amount of the target voxel is zero, the data value zero is stored in the displacement amount memory 53. Thereby, the average value of the displacement amount using the neighboring voxels is stored in the displacement amount memory 53 only when the target voxel has a non-zero displacement amount, that is, the voxel corresponding to the heart chamber surface.

  FIG. 6 is a diagram for explaining a three-dimensional displacement image in the present embodiment. FIG. 6A shows an example of an image when the displacement amount is not smoothed. FIG. 6B shows an example of an image when the displacement is smoothed. Note that FIG. 6 shows an image obtained by performing shading processing according to the amount of displacement on the surface of the ball-shaped sample that looks like a heart chamber, instead of coloring processing.

  In FIG. 6A, a relatively rough shading process can be confirmed on the sample surface, whereas in FIG. 6B, the shading process on the sample surface is smooth. As described above, the smoothing process is performed on the displacement amount, and then the display process (coloring process and shading process) is performed on the portion on the surface, thereby smoothening the result of the display process.

  As mentioned above, although preferred embodiment of this invention was described, embodiment mentioned above is only a mere illustration in all the points, and does not limit the scope of the present invention. The present invention includes various modifications without departing from the essence thereof.

1 is a functional block diagram showing an overall configuration of an ultrasonic diagnostic apparatus according to the present invention. It is a block diagram which shows the internal structure of an edge detection means. It is a figure for demonstrating the detection method of the displacement amount in this embodiment. It is a figure for demonstrating the smoothing process with respect to displacement amount. It is a functional block diagram for demonstrating the internal structure of a displacement amount smoothing part. It is a figure for demonstrating the three-dimensional displacement image in this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Probe, 12 Transmission / reception part, 14 Three-dimensional data memory, 50 Displacement amount detection part, 56 Coloring process part, 58 Image composition part, 60 Display image formation part, 80 Displacement amount smoothing part

Claims (5)

A wave transmitting / receiving means for collecting a plurality of voxel data for each time phase from within a three-dimensional space including the target tissue by transmitting and receiving ultrasonic waves;
A displacement amount calculating means for calculating a displacement amount for each part on the surface of the target tissue based on a plurality of voxel data collected for each time phase;
Displacement after smoothing is performed for each part by applying a smoothing process to the displacement amount of each part calculated by the displacement amount calculation means using the displacement amount of the neighboring part existing in the vicinity of the part. Smoothing means for calculating the quantity;
In the three-dimensional image data formed for each time phase based on a plurality of voxel data, the pixel data corresponding to each part on the target tissue surface corresponds to the displacement amount after the smoothing process of the part Displacement image forming means for forming three-dimensional displacement image data by performing display processing;
Display image forming means for forming a display image based on the three-dimensional displacement image data;
Having
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 1,
The smoothing means calculates the average value of the displacement amount of each part calculated by the displacement amount calculation means and the displacement amount of at least one neighboring part on the target tissue surface adjacent to the part, and calculates the average The value is the amount of displacement after smoothing the part,
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 2,
The displacement amount calculation means includes a reference point set on the basis of the structure of the target tissue and each of the surface on the target tissue in the three-dimensional data space constituted by a plurality of voxel data collected from the three-dimensional space. By tracking the movement of each part along the straight line connecting the parts, the amount of displacement is calculated for each part.
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 3.
The displacement amount calculating means calculates the displacement amount of the part from the spatial distance between two voxel data of different time phases corresponding to the part existing on or near the straight line connecting the reference point and each part. calculate,
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to any one of claims 1 to 4, wherein
The displacement image forming means performs a coloring process according to a displacement amount after the smoothing process of each part as the display process.
An ultrasonic diagnostic apparatus.