JP4359749B2 - Movement display method and diagnostic imaging apparatus for living tissue - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a motion display method for a living tissue such as a moving myocardium, which is applied to an ultrasound diagnostic image, a magnetic resonance image, or an X-ray CT image, and an image diagnostic apparatus using the method.
[0002]
[Prior art]
Image diagnostic apparatuses such as an ultrasonic diagnostic apparatus, a magnetic resonance imaging (MRI) apparatus, and an X-ray CT apparatus are all provided for diagnosis by displaying a tomographic image relating to the examination site of the subject on a monitor. For example, in the case of a circulatory system such as the heart and blood vessels and other organs with movement, the movement of living tissues (hereinafter referred to as tissues) constituting them is observed by a tomographic image, and the functions of the organs and the like are observed. Diagnosis is going on.
[0003]
In particular, if the motor function such as the heart can be quantitatively evaluated, it is expected that the accuracy of diagnosis is further improved. For example, conventionally, the contour of the heart wall is extracted from the image obtained by the ultrasonic diagnostic apparatus, and the heart function (heart pump function) is calculated based on the heart wall contour based on the area and volume of the ventricle and the rate of change thereof. Attempts have been made to evaluate or to observe and diagnose local wall motion (Patent Document 1). In addition, the displacement of the tissue is measured based on a measurement signal such as a Doppler signal, and for example, a local contraction or relaxation distribution is imaged. Based on this, the location where the ventricular motion is activated is accurately determined. Or a method for quantitatively measuring tissue motion, such as measuring the thickness (wall thickness) of a ventricular wall during systole (Patent Document 2). Furthermore, a technique has been proposed in which the contours of the atria and ventricles that change from time to time are extracted, the contours are superimposed on the image, and the volume of the ventricles and the like is calculated based on the contours (Patent Document 3).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-13145 [Patent Document 2]
JP-T-2001-518342 [Patent Document 3]
US Pat. No. 5,322,067 (USP 5,322,067)
[0005]
[Problems to be solved by the invention]
However, any of the above conventional techniques is only a method for evaluating the overall function of the heart, and no consideration is given to quantitatively evaluating the movement of each tissue such as the myocardium. In particular, the conventional technique for extracting the outline of the heart wall by image processing and measuring the thickness (wall thickness) of the ventricular wall based on the outline or measuring the change in the wall thickness is not necessarily sufficient to obtain sufficient accuracy. Has not reached.
[0006]
In general, for example, if blood does not pass through the myocardium due to a thrombus or the like, the movement of the myocardium is said to decrease. Therefore, if the movement of each tissue of the heart, such as the movement of the myocardium constituting the ventricle and the change in the wall thickness, can be measured quantitatively, it is possible to provide effective diagnostic information when determining the treatment method. For example, if the degree of ischemia is known, it is effective as an index for selecting a treatment method for the heart such as coronary artery regeneration and specifying a treatment site.
[0007]
In particular, since the heart circulates blood by repeatedly contracting and expanding, a scoring method has been proposed in which the degree of change in myocardial wall thickness is scored for diagnosis. In this scoring method, for example, the heart wall is divided into six in the extending direction of the heart wall, and the degree of wall thickness movement for each divided region is evaluated in five stages while observing a moving image. . In addition, this scoring is divided into four modes: a normal state, a load I state in which a patient exercises a load on the heart, a load II state in which a greater load is applied, and a state in which the load is removed and recovered. The diagnosis of the heart is also performed.
[0008]
However, since conventional scoring must be evaluated by subjective judgment of the observer who observed the motion of the heart based on the moving image of the tomogram, the scoring result is not necessarily objective and accurate diagnosis There is a problem that considerable experience is required to do.
[0009]
Therefore, the inventors of the present invention set a pair of tracking points (marks) on the inside and outside of the myocardial wall on the monitor on which the tomographic image of the heart is displayed, and move the cutout image including the tracking points on the moving image. The tip is detected by image processing such as correlation method, and the tracking point is moved and superimposed according to the movement of the myocardial wall, while the distance (wall thickness) between the pair of tracking points is quantified based on the tracking result It proposes to measure automatically (Japanese Patent Application No. 2002-266864).
[0010]
However, since there is not enough consideration about the specific method of displaying the ventricular wall thickness data measured quantitatively, there was a point to be improved when the viewer made an accurate diagnosis.
[0011]
The subject of this invention is improving the display method of the movement of the predetermined part of the biological tissue which has a motion, such as the ventricular wall thickness measured quantitatively.
[0012]
[Means for Solving the Problems]
Movement display method of the biological tissue of the present invention for solving the above-mentioned problem, the displays on the display unit reads one frame image from the image storage unit for moving image sections ing by imaging the tissue is stored with motion A first step, a second step of setting at least a pair of marks facing each other across a predetermined part on the displayed one frame image, and a motion of the predetermined part of the part where each mark is set And performing a third step of tracking above and a fourth step of changing the position of each mark in accordance with the movement of the predetermined portion and obtaining the distance between the pair of marks after the change. . Further, a fifth step of obtaining at least one momentum of the distance between the pair of marks, the rate of change of the distance, and the rate of change of the distance, and the momentum of the predetermined portion at the position of each pair of marks is defined as A motion display image in which at least one of luminance and color is changed is displayed on the display unit, and the first to sixth steps are executed for the tomographic image of the tissue having the motion. Can be.
[0013]
According to the biological tissue motion display method of the present invention as described above, a tissue movement, for example, a change in wall thickness, which is a movement of the myocardium , is associated with a mark position as a change in luminance or color instead of a numerical value. Since it is displayed, the score of each divided region regarding the movement of the myocardium can be evaluated at a glance based on the luminance and the color. Therefore, the variation in evaluation can be reduced as compared with the case where the qualitative evaluation is subjectively performed for each observer. Here, the above-mentioned step of tracking the movement of the part (for example, myocardium) where each mark is set on the moving image sets the cut image having a size including the mark as the one-frame image, Searching other frame images of the moving image to extract a local image of the same size having the highest matching degree between the cut-out image and the image, and based on a coordinate difference between the local image having the highest matching degree and the cut-out image And determining the movement destination of the mark. In this case, the extracted local image is used as a new cut-out image, a step of extracting the local image having the highest match with the other frame images of the moving image, and the local image and the cut-out image having the highest matching degree are extracted. It is also possible to repeatedly perform the step of obtaining the movement destination of the mark based on the coordinate difference and sequentially obtain the movement destination of the mark, thereby moving and displaying the mark following the movement of the myocardium.
[0014]
The image diagnostic apparatus of the present invention includes a display unit displaying an image storage unit for moving image data that is obtained by imaging a tomographic tissue having a motion is stored, a tomographic image of the tissue, the image storage Display control means for reading out the moving image data stored in the means and displaying a moving image or a still image on the display unit, and at least a pair facing each other across a predetermined part on the still image displayed on the display unit An operation unit for setting the mark, and a cutout image including each mark is set in the still image displayed on the display unit, and the moving destination of the cutout image is based on the moving image displayed on the display unit A cut-out image tracking means for tracking the movement, a movement amount calculating means for obtaining a movement amount of each mark based on a movement destination of the cut-out image, and a tomographic image having a different movement based on the movement amount. It can be constructed and an image generating means for displaying on said display unit to generate a display image. Furthermore, a motion calculation means for obtaining at least one momentum of a distance between the pair of marks, a change rate of the distance, and a change speed of the distance based on the movement amount of each mark obtained by the movement amount calculation means. The image generation means may be configured to generate the motion display image by changing at least one pixel value of luminance and color according to the amount of motion obtained by the motion calculation means.
[0015]
In the present invention, it is preferable to display the exercise display images in each load state side by side on the display screen, but the exercise display images in each load state may be sequentially displayed in time series. In addition, it is desirable to divide one cycle of the heart into a plurality of time phases and display the time phases of the motion display images of the heart in different load states side by side. Furthermore, it is preferable to align and display the electrocardiogram measured by the electrocardiograph and the electrocardiogram measured by the electrocardiograph in alignment with the motion display image of the present invention.
[0016]
A specific motion display image can be displayed with one axis of the rectangular region corresponding to the set positions of a plurality of pairs of marks arranged along the myocardium and the other axis corresponding to the time axis. In this case, there is provided a step of displaying on the display unit a graph representing a change in momentum along the designated line by inputting and setting a line designating at least one of the time of the rectangular area and the setting positions of the plurality of pairs of marks.
[0017]
As another specific example of the motion display image, an image in which at least one of luminance and color of a region corresponding to the myocardium of the moving image at each pair of mark positions is changed according to the amount of motion at the position, or the inner wall of the myocardium And an image in which at least one of the luminance and color of the area corresponding to each pair of mark positions in the schematic figure is changed according to the momentum at the position is superimposed on the schematic figure simulating the outer wall. it can. In particular, by displaying a motion display image superimposed on a schematic figure of the myocardium, it is possible to directly diagnose a site where the myocardial movement is bad.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
An image diagnostic apparatus according to an embodiment to which the heart motion display method of the present invention is applied will be described with reference to FIGS. FIG. 1 shows the procedure of the heart motion display method of this embodiment, and FIG. 2 is a block diagram of an image diagnostic apparatus to which the heart motion display method of FIG. 1 is applied. As shown in FIG. 2, the diagnostic imaging apparatus inputs an image storage unit 1 that stores a moving image obtained by imaging a tomogram of a living body that is a subject, a display unit 2 that displays an image, and various commands. An operation console 3, an automatic tracking unit 4 that tracks the movement of the heart of a moving image displayed on the display unit 2, and a tracking result of the automatic tracking unit 4 or based on measurement information of the motion calculation unit 6. An image generation storage unit 5 that generates and stores an exercise display image, an exercise calculation unit 6 that calculates various measurement information based on the tracking result of the automatic tracking unit 4, and a signal transmission path 7 formed by connecting them. It is configured to include.
[0019]
In the image storage unit 1, a moving image obtained by capturing a tomographic image of a subject from the diagnostic image capturing apparatus 8 indicated by a broken line is stored online or offline. As the diagnostic image imaging apparatus 8, diagnostic apparatuses such as an ultrasonic diagnostic apparatus, a magnetic resonance imaging (MRI) apparatus, and an X-ray CT apparatus can be applied. In the present embodiment, for example, four-state moving images obtained by capturing tomographic images of the heart under different exercise loads of the subject are stored. That is, the normal load state A, the load I state B in which the patient is exercised to load the heart, the load II state C in which a larger load is applied, and the state D in which the load is removed and recovered A moving image of the aspect is stored. In addition, it is preferable that these tomographic images are captured in synchronization with an electrocardiogram waveform output from an electrocardiograph (not shown), and the electrocardiographic waveform is stored in synchronization with the tomographic image. However, the time axis is synchronized and stored.
[0020]
The console 3 superimposes a mark (mark) on a part of a living tissue whose movement is desired to be tracked on the still image displayed on the still image displayed on the still image displayed on the display unit 2. Various commands such as a command to be displayed and a command to select the type of image to be displayed on the display unit 2 can be input. When setting a mark, four still images of four different load states A to D may be displayed side by side, or may be displayed separately at different times.
[0021]
The automatic tracking unit 4 includes a control unit 10 that controls the entire image diagnostic apparatus, a display control unit 11 that controls switching of an image displayed on the display unit 2, and a mark position of one frame image displayed on the display unit 2. A cut-out image setting unit 12 that sets a cut-out image having a size including the corresponding tracking part, and another frame image of the moving image is read out from the image storage unit 1 and the cut-out image and the local image of the same size having the highest degree of coincidence between the images. Cutout image tracking means 13 for extracting an image, movement amount calculation means 14 for obtaining the coordinate difference between the local image having the highest degree of coincidence and the cutout image, and movement tracking means for obtaining the movement destination coordinates of the tracking portion based on the coordinate difference 15. The movement destination of the tracking part (mark) obtained by the movement tracking unit 15 may be sequentially stored according to the moving image to generate a tracking image of the moving image.
[0022]
On the other hand, the motion calculation unit 5 quantitatively calculates measurement information, which is a physical quantity related to movement such as the movement amount, movement speed, and movement direction of the tracking part, based on the movement destination coordinates of the tracking part obtained by the automatic tracking part 4. It has a function of obtaining and displaying the change of the measurement information on the display unit 2 with a diagram. In particular, the motion calculation unit 5 according to the present embodiment obtains the distance between a pair of marks set to face the inner and outer walls of the myocardium based on the amount of movement of the tracking region as the wall thickness of the myocardium, and the wall of the myocardium. It has a function of obtaining momentum such as change in thickness, rate of change in wall thickness, and rate of change in wall thickness.
[0023]
Further, the image generation storage unit 9 has a function of generating and storing a motion display image in which at least one of luminance and color is changed according to the amount of motion of the myocardium obtained by the motion calculation unit 5. It is configured. In particular, an exercise display image is created for each of four different load states A to D. The electrocardiographic waveform measured by the electrocardiograph is configured to be displayed in synchronization with the motion display image.
[0024]
The display control unit 11 reads out the moving image data stored in the image storage unit 1 in accordance with a command input from the console 3, and displays the moving image or the still image and the exercise stored in the image generation storage unit 5. It has a function of switching or displaying the displayed images.
[0025]
Next, the detailed functional configuration of the diagnostic imaging apparatus of the present embodiment will be described along with the operation according to the processing procedure shown in FIG. First, the motion tracking operation of the heart muscle starts when a command for selecting the tissue motion tracking mode is input from the console 3 (S1). The display control means 11 reads the first frame image ft (t = 0) of the moving image from the image storage unit 1 and displays it on the display unit 2 (S2). For example, it is assumed that a tomographic image of the heart ventricle 21 shown in FIG. 3 is displayed as the first frame image f0. In FIG. 3, when the operator wants to select a specific part of the myocardium 22 as a tracking part of the biological tissue whose movement is to be tracked, the operator operates the mouse or the like of the operation unit 3 to superimpose the tracking part on the frame image f0. The tracking point 23 which is a mark for setting is displayed. Then, the tracking point 23 is moved to be superimposed on the desired tracking part, and the tracking part is input and set. When measuring the wall thickness of the myocardium, which is a feature of the present invention, as shown in FIG. 6A, a pair of tracking points 23 facing each other with the myocardium 23 in between are input and set. In FIG. 3, reference numeral 24 denotes a mitral valve.
[0026]
When the tracking point 23 is input and set, the control means 10 takes in the coordinates of the tracking point 23 on the frame image f0 and sends it to the cutout image setting means 12 (S3). As shown in FIG. 4A, the cut-out image setting means 12 cuts out a rectangular area having a size of 2 (A + 1) pixels in length and width (A is a natural number) around the image of each tracking point 23. (S4). Here, the size of the cut-out image 25 is preferably set in a region having a size including a living tissue different from the living tissue of the tracking point 23.
[0027]
The cutout image tracking unit 13 reads the next frame image f1 of the moving image from the image storage unit 1, and extracts a local image of the same size having the highest degree of matching between the cutout image 25 and the image (S5). This extraction process is image processing called a so-called block matching method or correlation method. If this extraction process is performed for the entire region of the frame image f1, it takes too much processing time. Therefore, in order to shorten the extraction processing time, in the present embodiment, the search area 26 shown in FIG. 4B, which is sufficiently smaller than the frame image f1, is performed. That is, the search area 26 is a rectangular area in which the number of pixels B having a fixed swing width is added to the cutout image 25 in the vertical and horizontal directions. This pixel number B is larger than the amount of movement of the tissue related to the tracking region, and is set to 3 to 10 pixels, for example. This is because the range of movement of the circulatory system such as the heart is limited to a narrow region in a normal visual field. In this way, the local image 27 having the same size in the search area 26 is sequentially shifted to obtain the degree of coincidence with the cut image 25. FIG. 5 shows a specific example of image tracking processing by the correlation method. In this example, in order to simplify the explanation, the size of the cut-out image 25 is assumed to be a rectangular 9-pixel area, and the search area 26 is also assumed to be a rectangular 25-pixel area. That is, the cutout image 25 shown in FIG. 10A is an example in which A = 1 pixel is set around the pixel of the tracking point 23, and the search area 26 shown in FIG. This is an example. According to this, as shown in FIG. 5B, the image coincidence degree is obtained for nine local regions 27. Various known methods can be applied to the method for obtaining the degree of coincidence of images.
[0028]
Next, a local image 27max having the highest image matching degree is extracted from the plurality of searched local images 27, and the local image 27max is set as a movement destination of the cut image 25 to obtain the coordinates of the local image 27max (S6). The coordinates of these images are represented by the coordinates of the center pixel or the coordinates of any corner of the rectangular area. Then, the coordinate difference between the local image 27max and the cut-out image 25 is obtained, and based on this, the movement destination coordinates of the tracking point 23 are obtained and stored. If necessary, the display control means 11 displays the mark of the tracking point 23 on the frame image f1 of the display unit 2 based on the movement destination coordinates of the tracking point 23 (S7). Note that the relative position of the tracking point 23 in the local image 27max and the cutout image 25 is treated as not changing.
[0029]
The motion calculation unit 6 calculates and stores various measurement information related to the movement of the tracking point 23, that is, the movement of the tissue of the tracking part, based on the movement destination coordinates of the tracking point 23 obtained in S7 (S8). That is, the movement direction and the movement amount can be quantitatively measured based on the coordinates of the tracking point 23 before and after the movement. In this embodiment, the wall thickness of the myocardium 23 is calculated from the distance between the pair of tracking points 23, and the change, rate of change, and rate of change of the wall thickness are calculated according to the command and stored (S9). Instead of or in addition to this, it is possible to quantitatively obtain measurement information that is a physical quantity relating to movement such as the movement amount, movement speed, and movement direction of the tracking region. And the various measurement information regarding the movement of the tracking point 23 calculated | required and its change can be displayed on a display part with a graph. Thereby, the viewer can easily observe the movement of the tracking portion.
[0030]
Next, it progresses to step S10, it is judged whether tracking of the tracking point 23 was complete | finished about all the frame images of a moving image, and if there exists an unprocessed frame image, it will return to step S5 and will perform the process of S5-S10. repeat. When the tracking of the tracking point 23 is completed for all the frame images, the tracking processing operation is ended and the movement history data of the tracking point 23 is stored. Next, the image generation storage unit 5 generates a motion display image of the designated wall thickness change, rate of change, and rate of change, and displays the motion display image on the display unit. A specific example of this display image will be described later. As described above, according to the present embodiment, the coordinates of the movement destination of the tracking point 23 can be obtained sequentially, so that the movement of the tracking portion can be easily measured quantitatively and accurately, and diagnostic information can be obtained. Can be provided accurately.
[0031]
Next, a specific example of the heart motion display method, which is a feature of the present invention, will be described with reference to FIGS. First, a command is input from the console 3 to display a tomographic image of the heart on the display unit 2. At this time, as shown in FIG. 6A, still images of four tomographic images having different exercise loads are displayed. On this still image, a plurality of pairs (1 to n) of tracking points 23 are set along the myocardium 22 across the heart wall, and the tracking process is executed by switching to a moving image. In FIG. 6A, only one tomographic still image is shown. However, when necessary, as shown in FIG. 7A, still images of four states A to D in the same time phase. Can be displayed side by side, and a plurality of pairs (1 to n, where n is a natural number) of tracking points 23 can be set for each of the states A to D. When the setting of a plurality of pairs (1 to n) of tracking points 23 is completed in this way, the automatic tracking unit 4 operates to track the movement of each tracking point 23 for each of the states A to D. The motion calculation unit 6 measures the distance (wall thickness) between the tracking points 23 of each pair (1 to n) based on the measurement result of the movement amount of each tracking point 23, and FIG. As shown in c), the wall thickness change and rate of change at an arbitrary pair of tracking points 23 are measured, a graph of the wall thickness change and rate of change is created in the image generation storage unit 5, and the display unit 2 It can be displayed. Thereby, the movement of the myocardium accompanying the expansion and contraction and expansion of the heart can be grasped quantitatively.
[0032]
However, in order to compare the wall thickness change and rate of change between a plurality of pairs (1 to n) of tracking points 23, a large number of graphs measured for each of n pairs of tracking points 23 must be displayed side by side. It becomes complicated and impractical. That is, when scoring is performed for a region obtained by dividing the heart's motor function into six parts, even if the average value of the wall thickness change in each divided region of the myocardium 22 is displayed as a graph, six graphs are displayed side by side. Therefore, the comparative observation becomes complicated.
[0033]
Therefore, as shown in FIG. 8A, it is conceivable to display a three-dimensional graph of the change in wall thickness corresponding to each of the states A to D. In the figure, the horizontal axis represents time, the vertical axis represents the wall thickness change rate, the depth axis represents the measurement site along the myocardium 22, and the measurement was started when the heart was most expanded. It is the result measured about one period until it expands again from a systole. In this way, if it can be displayed as a three-dimensional image, it will be easier to see to some extent, but in this embodiment, the change in the wall thickness of the myocardium (momentum) is not changed along the time axis. It is characterized by generating and displaying a colored exercise display image.
[0034]
As an example of the exercise display image, as shown in FIG. 8B, a rectangular display area 30 is set on the display screen of the display unit 2, the horizontal axis is a time axis, and the vertical axis is a measurement part. Changes in the wall thickness (momentum) of the myocardium at each measurement site are displayed in the display area with luminance changes or colorization along the time axis. This figure is schematically shown. In the figure, the auxiliary line corresponds to the equal thickness line of the wall thickness, the region r1 surrounded by each auxiliary line is a low level wall thickness change region, and the region r2 is a medium level. The wall thickness change region, r3, indicates a high level wall thickness change region, and each of these regions is displayed by continuously changing the luminance (shading) or color according to the continuous wall thickness change. As is apparent from the figure, it can be seen at a glance that the wall thickness change near the middle of the myocardium is delayed compared to other regions, while the wall thickness change at both ends of the myocardium is severe. For example, when the wall thickness change is small, the luminance is set to the minimum value (for example, black), and the luminance is increased as the wall thickness change becomes intense. This exercise display image is created and stored by the image generation storage unit 5 based on the measurement result of the exercise calculation unit 6.
[0035]
Instead of the display shown in FIG. 8B, exercise display images shown in FIGS. 9 to 11 can be formed. That is, in FIG. 9, a schema that is a simulated image of the myocardium can be displayed on the display unit, and a motion display image as shown in FIG. 8B can be superimposed on the image. According to this example, since the wall thickness change of the part corresponding to the shape of the myocardium is displayed, the motion state of the myocardium is very easily recognized. In particular, by observing the change in the region r3 where the wall thickness changes drastically in the four states A to D, for example, in the state C corresponding to the load II state, it can be observed that r3 divided into two places is connected. This means, for example, that if the exercise is intense, the blood flow is improved and the myocardium starts to move. Therefore, it can be diagnosed that the myocardium in this portion has room for recovery. The measurement site corresponds to the tomographic image of the myocardium, and the temporal change in the amount of exercise is displayed as a moving image.
[0036]
FIG. 10 is an example in which four states A to D of an exercise display image similar to those in FIG. 8B are displayed side by side, with the horizontal axis corresponding to time and the vertical axis corresponding to the measurement site. FIG. 11 is an example in which the wall thickness change at a specific myocardial position is graphed and the four states A to D are shown side by side, with the horizontal axis representing time and the vertical axis representing wall thickness change. In the case of FIG. 11, by operating the console 3 and inputting a designated line to the measurement site in the display area 30, the wall thickness change at the measurement site on the designated line is displayed as a graph.
[0037]
FIGS. 8B to 11 are examples of motion display images of changes in the wall thickness of the myocardium. However, the change rate of the wall thickness or the change rate of the wall thickness can be similarly imaged and displayed. For example, when imaging the rate of change of wall thickness, a motion display image of the rate of change of wall thickness is generated and displayed with “red” as the direction of change in wall thickness and “blue” as the direction of decrease in thickness. can do. The wall thickness change rate can be obtained by obtaining wall thickness change rate data based on the measurement result of the motion calculation unit 6, generating a motion display image based on the data, and displaying the motion display image on the display area.
[0038]
As described above, according to the above-described embodiment, the following effects can be obtained. First, if the heart movement is biased to only one side after the heart surgery, or if you want to inspect the part where the blood circulation is poor by observing the part where the change in the wall thickness of the myocardial wall is small, mark the tracking point. Even if the movement display is performed following the movement of the myocardium, it is difficult to observe the subtle difference in the change in the wall thickness because the whole heart wall is confused. In this regard, according to the above embodiment, the momentum such as the change in wall thickness of each measurement site of the myocardium corresponding to the position of the mark is displayed by the difference in brightness, color, etc. It is possible to detect a symptom in which the motion of the heart is biased or a site where blood circulation is poor, which is a site where the change in wall thickness is small.
[0039]
In particular, when evaluating the function of the heart by scoring, the heart wall is generally divided into six along the heart wall of the heart, and the degree of change in wall thickness is divided into five stages for each divided region. “5”, “1” when there is no movement, and “2” to “4” according to the degree of movement in the middle. Furthermore, there are four modes: a normal state A, a load I state B in which the patient is exercised to load the heart, a load II state C in which a greater load is applied, and a state D in which the load is removed and recovered Scoring is performed to diagnose the heart. In this case, there is a problem that the scoring result varies when the degree of movement is determined by the subjective judgment of the viewer and given a score. In this regard, according to the present embodiment, the change in wall thickness, that is, the movement of the myocardium can be quantitatively discriminated based on the difference in brightness or the difference in color. Evaluation can be performed, and the same evaluation result can be obtained even by a viewer with little experience. In particular, since four states can be observed in comparison, evaluation with higher reliability can be performed.
[0040]
In addition, since the motion of the myocardium can be recognized quantitatively, it is possible to identify, for example, the ischemic site or the degree of ischemia in ischemic heart disease. Can be used as an indicator.
[0041]
Further, in the above-described embodiment, in order to observe the movement of the myocardium finely, the number of tracking points 23 that are marks of the tracking site is input and set from the console 3, and the setting work is complicated. Therefore, when the tracking point 23 is set along the myocardial wall, an interval is appropriately provided for a portion where the tissue shape changes gently according to the operator's judgment, and an interval is provided for a portion where the tissue shape changes greatly. You may make it set narrowing. In this case, it is preferable that the tracking point 23 is automatically complemented and set at a close interval by the control means 10.
[0042]
Moreover, although the above-mentioned embodiment demonstrated the example performed offline, if the speed concerning an image tracking process is improved, it can be applied also to an online or real-time moving image. In addition, although a two-dimensional tomographic image has been described as an example, it goes without saying that the present invention can also be applied to a three-dimensional tomographic image.
[0043]
【The invention's effect】
As described above, according to the present invention, since the display method of the ventricular wall thickness measured quantitatively is improved, an accurate diagnosis can be performed.
[Brief description of the drawings]
FIG. 1 is a diagram showing a processing procedure of an embodiment of a biological tissue motion tracking display method of the present invention.
FIG. 2 is a block configuration diagram of an image diagnostic apparatus to which the biological tissue motion tracking display method of FIG. 1 is applied.
FIG. 3 is a diagram for explaining the application of motion tracking of a living tissue of the present invention to a tomographic image of the heart.
FIGS. 4A and 4B are diagrams for explaining an embodiment of an image tracking processing method according to the present invention, in which FIG. 4A is an example of a cut-out image, and FIG. 4B is an example of a search area; .
FIG. 5 is a diagram for explaining image tracking processing by a correlation method using a specific example;
FIG. 6 is an example in which a distance between a plurality of pairs of marks set across a heart wall and a change in the distance are measured and displayed as a graph.
FIG. 7 is an example diagram in which four myocardial tomographic images having different exercise loads for scoring the heart are displayed side by side.
FIG. 8 is a diagram showing an example of a graph showing a change in the wall thickness of the myocardium and an example of a motion display image that displays the change in the wall thickness along the time axis by changing the luminance or coloring.
FIG. 9 is a diagram showing an example in which a schema that is a simulated image of the myocardium is displayed on the display unit, and the four-state motion display image of the present invention is superimposed on the image.
FIG. 10 is a diagram showing an example in which motion display images for displaying a change in wall thickness along a time axis with luminance changes or colors are displayed side by side in four states.
11 is an example of a graph showing a change in wall thickness at the specific measurement site in FIG. 10; FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Image memory | storage part 2 Display part 3 Console 4 Automatic tracking part 5 Image generation memory | storage part 6 Motion calculation part 7 Signal transmission path 8 Diagnostic image imaging device 10 Control means 11 Display control means 12 Cutout image setting means 13 Cutout image tracking means 14 Movement amount calculation means 15 Movement tracking means

Claims (7)

  A first step of reading out one frame image from an image storage unit storing a moving image obtained by imaging a tomographic tissue having movement and displaying the frame on a display unit; and a predetermined region on the displayed one frame image A second step of setting at least a pair of marks opposed to each other, a third step of tracking the movement of the predetermined part on which each mark is set on the moving image, and the respective steps according to the movement of the predetermined part A fourth step of determining the distance between the pair of marks after changing the position of the mark, and determining at least one momentum of the distance between the pair of marks, the rate of change of the distance, and the rate of change of the distance; A fifth step and a sixth step of displaying on the display unit an exercise display image in which at least one of luminance and color is changed according to the amount of exercise of the predetermined part obtained in the fifth step. The motion display image is generated and input and set so that one axis of the rectangular region corresponds to a setting position of a plurality of pairs of marks arranged along the predetermined portion and the other axis corresponds to a time axis. A biological tissue motion display method including a seventh step of displaying on the display unit a graph representing a change in the amount of motion along a specified line that specifies at least one of the time of the rectangular region and the setting positions of a plurality of pairs of marks. .   The predetermined part is a predetermined part of an inner wall and an outer wall of a tissue having movement, and the motion display image is a schematic figure simulating the inner wall and the outer wall of the predetermined part, and each pair of marks in the schematic figure The method for displaying a movement of a living tissue according to claim 1, wherein an image in which at least one of luminance and color of a region corresponding to the position is changed according to the amount of movement at the position is superimposed and generated. . Image storage means for storing moving image data obtained by imaging a tomographic tissue having movement, a display unit for displaying the tomographic image of the tissue, and reading out the moving image data stored in the image storage means Display control means for displaying a moving image or a still image on the display unit, an operation unit for setting at least a pair of marks facing each other with a predetermined portion on the still image displayed on the display unit, and the display A cut-out image tracking means for setting a cut-out image including each of the marks in the still image displayed on the section and tracking the movement destination of the cut-out image based on the moving image displayed on the display section; A movement amount calculating means for calculating a movement amount of each mark based on a movement destination of the image; and a movement display image generated based on the movement amount obtained for each tomographic image having different movements, and And an image generating means for displaying on the radical 113,
Further, the image generation means is configured to display the motion display image in which one axis of the rectangular region corresponds to a setting position of a plurality of pairs of marks arranged along the predetermined portion, and the other axis corresponds to the time axis. The pair of marks based on the amount of movement obtained by the amount-of-movement calculating means along a designation line that designates at least one of the time of the rectangular area to be generated and set and the setting position of a plurality of pairs of marks. diagnostic imaging apparatus for displaying in front Symbol display unit to generate a graph showing the change in momentum between. The image diagnostic apparatus according to claim 3 , wherein the image generation unit displays the motion display images of the tomographic images having different motions side by side on a display screen. Based on the movement amount of each mark obtained by the movement amount calculation means, comprising a movement calculation means for obtaining at least one momentum of a distance between the pair of marks, a change rate of the distance, and a change speed of the distance;
The image diagnosis according to claim 3 , wherein the image generation unit generates the motion display image by changing at least one pixel value of luminance and color in accordance with the amount of motion obtained by the motion calculation unit. apparatus. The motion display image is an image in which at least one of luminance and color of an area corresponding to a predetermined part of the moving image at each pair of mark positions is changed according to the amount of movement at the position. The diagnostic imaging apparatus according to claim 3 . The motion display image is a schematic figure simulating the predetermined part, and at least one of luminance and color of an area corresponding to the pair of mark positions in the schematic figure is changed according to the amount of exercise at the position. The diagnostic imaging apparatus according to claim 3 , wherein the diagnostic imaging apparatus is generated by overlapping images.

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