JP6731275B2 - Ultrasonic diagnostic equipment - Google Patents

Description

The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an apparatus for forming a tissue trace line.

The ultrasonic diagnostic apparatus is an apparatus that forms and displays an ultrasonic image based on the reception data obtained by transmitting and receiving ultrasonic waves. Generally, the ultrasonic diagnostic apparatus has a plurality of operation modes (B mode, Doppler mode, etc.). Furthermore, an ultrasonic diagnostic apparatus having a plurality of measuring functions is also known. A preferable example of those measuring functions is a measuring function relating to the heart.

For example, Patent Document 1 describes a technique for automatically tracing the contour of the endocardium of the heart in an ultrasonic image as a technique for supporting measurement of the heart by ultrasonic waves. In Patent Document 1, a trace line (trace line) obtained by automatic tracing is composed of a plurality of control points (trace points).

Further, Patent Document 2 describes a technique of correcting a closed curve (trace line) set according to the shape of the left ventricle chamber. That is, a point selected from a plurality of points (a plurality of trace points) forming a closed curve (trace line) is moved in the direction instructed by the operator, and other points within the influence range near that point are also moved. A technique for forming a corrected closed curve by a plurality of points after the movement is described.

Japanese Patent No. 4085315 JP, 2005-28051, A

The present invention has been made in view of the background art described above, and an object thereof is to provide an improved technique related to correction of a plurality of trace points forming a trace line.

A suitable ultrasonic diagnostic apparatus that serves the above purpose is a movement processing unit that moves selected trace points among a plurality of trace points that form a trace line of a tissue in an ultrasonic image, and from among the plurality of trace points. A follow-up target determination unit that determines a follow-up trace point within a target range of the follow-up process with the selected trace point as a base point according to a constraint condition that the feature trace point corresponding to the feature point of the organization is not a target of the follow-up process. And a tracking processing unit that moves the tracking trace point so as to follow the movement of the selected trace point.

When forming a trace line indicating a boundary of a tissue in an ultrasonic image, it is desirable to use a feature point of the tissue that can be detected with relatively high accuracy in the ultrasonic image. This is because the feature trace points corresponding to such feature points of the organization can be respected with relatively high reliability. For example, the annulus of the heart in the ultrasonic image has a relatively high brightness and is one of the characteristic points suitable for detection. Further, the apex of the heart identified based on the positions of the two annulus portions is also one of the preferable feature points. Therefore, for example, when forming a trace line of the lumen of the left ventricle, three suitable points are two annulus portions and one apex.

On the other hand, the trace points other than the feature trace points are less reliable than the feature trace points because the accuracy of the boundary detection decreases in a part where the boundary of the tissue is ambiguous or a part with a lot of noise. There is a high possibility that it will be the target of the correction.

Therefore, the ultrasonic diagnostic apparatus with the above configuration determines the tracing trace point to be the subject of the tracing process according to the constraint condition that the characteristic trace point is not the subject of the tracing process, and traces the tracing so as to follow the movement of the selected trace point. Performs follow-up processing to move a point. The target range of the tracking process is preferably, for example, a range near the selected trace point. For example, when the user designates a selected trace point from a plurality of trace points and corrects the position, the trace points in the vicinity of the selected trace point are also tracked. In the tracking process, it is desirable that the characteristic trace points remain fixed and not moved.

As a result, it becomes possible to collectively correct, for example, the following trace points in the vicinity together with the selected trace point to be corrected while maintaining the relatively reliable feature trace point as it is.

In a preferred specific example, the tracking target determination unit sets the target range to be wider as the movement amount of the selected trace point is larger.

In a preferred specific example, the tracking target determination unit, when setting the target range extending from the selected trace point side to the characteristic trace point side, sets the target range so as not to exceed the characteristic trace point. Characterize.

In a preferred specific example, the tracking processing unit determines the amount of movement of the following trace point based on the amount of movement of the selected trace point and the distance from the selected trace point to the following trace point. ..

In a preferred specific example, the tracking processing section may move the tracking trace point in parallel in the same direction as the moving direction of the selected trace point.

In a preferred specific example, the ultrasonic diagnostic apparatus uses, as the characteristic trace points, a trace point corresponding to an apex of the heart and a trace point corresponding to an annulus of the plurality of trace points forming a trace line of a heart chamber. The tracking trace point is moved so as to follow the movement of the selected trace point while fixing the characteristic trace point.

In addition, the function corresponding to each unit included in the above-described suitable ultrasonic diagnostic apparatus (including a desirable specific example) may be realized by a computer (including a tablet terminal). For example, a movement processing function of moving a selected trace point among a plurality of trace points forming a trace line of a tissue in an ultrasonic image, and a feature corresponding to the feature point of the tissue from the plurality of trace points According to the constraint condition that the trace point is not the subject of the follow-up processing, the follow-up target determination function of determining the follow-up trace point within the target range of the follow-up processing with the selected trace point as the base point, and following the movement of the selected trace point A computer can be caused to function as the above-described suitable ultrasonic diagnostic apparatus by a program that causes the computer to implement the following processing function of moving the following trace point. The program may be stored in a computer-readable storage medium such as a disk or a memory and provided to the computer via the storage medium, or may be provided to the computer via a telecommunication line such as the Internet. May be provided.

The present invention provides an improved technique for correcting a plurality of trace points forming a trace line. For example, according to a preferred aspect of the present invention, while maintaining relatively reliable feature trace points, for example, as they are, the selected trace points to be corrected and the following trace points in the vicinity are also collectively corrected. It becomes possible to do.

It is a figure which shows the specific example of an ultrasonic diagnosing device suitable for implementation of this invention. It is a figure which shows the specific example of a trace line. It is a figure which shows the specific example of the object range and movement amount of a tracking process. It is a figure for demonstrating the setting pattern of a target range. It is a figure which shows the specific example of a process until the movement amount of a following trace point is determined. It is a figure which shows the specific example 1 of correction of a trace line. It is a figure which shows the specific example 2 of correction of a trace line.

FIG. 1 is a diagram showing a specific example of an ultrasonic diagnostic apparatus suitable for implementing the present invention. The probe 10 is an ultrasonic probe that transmits and receives ultrasonic waves to and from tissues in the living body, for example, a region including the heart of the subject. The probe 10 includes a plurality of vibrating elements, and the plurality of vibrating elements are electronically scan-controlled to scan an ultrasonic beam in a space including the heart. The probe 10 is used, for example, by being grasped by a user such as a doctor or a laboratory technician and abutting on the body surface of the subject. The probe 10 may be a probe that combines electronic scanning and mechanical scanning.

The transmission/reception unit 12 has the functions of a transmission beam former and a reception beam former. That is, the transmission/reception unit 12 forms a transmission beam by outputting a transmission signal to each of the plurality of vibrating elements included in the probe 10, and further, for a plurality of received signals obtained from the plurality of vibrating elements. A reception beam is formed by performing phasing addition processing and the like. As a result, the ultrasonic beams (transmission beam and reception beam) are scanned in the scanning plane, and while the reception signals (reception data) corresponding to the ultrasonic beams are collected, a plurality of frames (a plurality of scanning phases) corresponding to a plurality of time phases are acquired. Frame) is formed. In order to obtain the reception signal of the ultrasonic wave, the ultrasonic beam may be three-dimensionally scanned in the tertiary space, or a technique such as transmission aperture synthesis may be used.

The image forming unit 20 forms an ultrasonic image (image data) on the basis of an ultrasonic wave reception signal (reception data) that forms each frame, which is obtained from the transmission/reception unit 12. The image forming unit 20 forms a plurality of frames of tomographic images (B-mode images), for example, by performing detection processing, filter processing, AD conversion processing, or the like on the received ultrasonic signals.

The image forming unit 20 forms image data in a scanning coordinate system corresponding to ultrasonic scanning, for example, in an rθ coordinate system based on the r direction corresponding to the beam depth direction and the θ direction corresponding to the beam scanning direction. Image data obtained in the scanning coordinate system (for example, rθ coordinate system) is preferably subjected to coordinate conversion processing by, for example, a digital scan converter to be converted into image data for the display coordinate system (for example, xy orthogonal coordinate system). .. The function of the digital scan converter is provided in, for example, the image forming unit 20 or the display processing unit 50.

The image storage unit 22 stores image files of a plurality of ultrasonic moving images. Each image file is moving image data composed of a plurality of tomographic images (moving B-mode images) formed in the image forming unit 20. The image storage unit 22 stores, for example, a plurality of image files corresponding to a plurality of dates and times regarding the heart of the same subject, a plurality of image files regarding hearts of a plurality of subjects, and the like.

In addition, it is desirable that each image file stored in the image storage unit 22 is associated with electrocardiographic waveform information. That is, it is desirable that the time phases of a plurality of frames and the time phase of the electrocardiographic waveform that make up each image file are associated with each other. Accordingly, for example, it is possible to specify, among a plurality of frames forming each image file, a frame corresponding to a characteristic time phase (for example, R wave) in the electrocardiographic waveform.

The image selection unit 30 selects each image file used for diagnosis or measurement of the heart from the plurality of image files stored in the image storage unit 22. For example, a display image showing the contents of a plurality of image files stored in the image storage unit 22 (a list of thumbnail images of typical frames included in each image file, etc.) is displayed on the display unit 52, and a doctor or a technologist is displayed. While operating the operation device 60 while viewing the displayed image, the user specifies at least one image file used for heart diagnosis and measurement. The image selection unit 30 selects at least one image file designated by the user.

The trace line processing unit 40 processes a trace line used for diagnosis or measurement of the heart based on each image file selected by the image selection unit 30. The trace line processing unit 40 includes a trace line forming unit 42, a selection point movement processing unit 44, a tracking target determination unit 46, and a tracking processing unit 48. The processing relating to the trace line executed by the trace line processing unit 40 will be described in detail later.

The display processing unit 50 forms a display image including a moving image regarding a cross section of the heart based on the tomographic images of a plurality of frames obtained from the image forming unit 20. The display processing unit 50 also displays a moving image corresponding to each image file stored in the image storage unit 22 and a display image showing the contents of a plurality of image files stored in the image storage unit 22 (for example, in each image file (Eg, a list of thumbnail images of representative frames included). Further, the display processing unit 50, based on each image file for diagnosis or measurement selected by the image selection unit 30 and the trace result obtained from the trace line processing unit 40, as a display image related to heart diagnosis or measurement, Form a display image of the heart with trace lines set. The display image formed by the display processing unit 50 is displayed on the display unit 52.

The control unit 100 generally controls the inside of the ultrasonic diagnostic apparatus of FIG. An instruction received from a user such as a doctor or an inspection technician via the operation device 60 is also reflected in the overall control by the control unit 100.

In the configuration (each part denoted by reference numeral) shown in FIG. 1, the transmitting/receiving section 12, the image forming section 20, the image selecting section 30, the trace line processing section 40 (the trace line forming section 42, the selected point movement processing section 44, the tracking target). Each unit of the determining unit 46, the follow-up processing unit 48), and the display processing unit 50 can be realized by using hardware such as an electric/electronic circuit or a processor. May be used. Further, at least a part of the functions corresponding to each of the above units may be realized by a computer. That is, at least a part of the functions corresponding to the respective units may be realized by the cooperation of the hardware such as the CPU, the processor, and the memory, and the software (program) that defines the operation of the CPU and the processor.

The image storage unit 22 can be realized by a storage device such as a semiconductor memory or a hard disk drive. A preferred specific example of the display unit 52 is a liquid crystal monitor or the like. The operation device 60 can be realized by, for example, at least one of a mouse, a keyboard, a trackball, a touch panel, and other switches. The control unit 100 can be realized by, for example, cooperation between hardware such as a CPU, a processor, and a memory, and software (program) that defines the operation of the CPU and the processor.

The overall configuration of the ultrasonic diagnostic apparatus of FIG. 1 is as described above. Next, the heart tracing process realized by the ultrasonic diagnostic apparatus of FIG. 1 will be described in detail. In addition, regarding the configuration (part) shown in FIG. 1, the reference numerals of FIG. 1 are used in the following description.

FIG. 2 is a diagram showing a specific example of the trace line. In FIG. 2, in a tomographic image (B-mode image) representing the left ventricle of the heart, trace lines corresponding to the boundary between the left ventricle, that is, the boundary between the myocardium and the heart chamber are shown by broken lines. Further, in the specific example of FIG. 2, a plurality of circles arranged along a broken line which is a trace line is a plurality of trace points.

The trace line forming unit 42 forms a trace line in a frame (reference frame) serving as a reference included in a plurality of frames forming each image file (moving image) selected by the image selecting unit 30, for example. A trace line consists of multiple trace points. For example, as in the specific example shown in FIG. 2, a trace line is formed so as to connect a plurality of trace points. The trace line forming unit 42 sets (forms) a trace line by, for example, one of manual setting (manual setting), semi-auto setting (designating a plurality of points), and full auto setting (fully automatic tracing).

In the manual setting, all of the plurality of trace points are set by the user. A user such as a doctor or an inspection technician operates the operation device 60 while confirming the display image displayed on the display unit 52, determines a reference frame from a plurality of frames, and determines the reference frame in the image of the reference frame. The position of each trace point is specified to set a plurality of trace points on the contour of the tissue. For example, if the site to be diagnosed is the left ventricle, a plurality of trace points are set on the boundary of the endocardium of the left ventricle.

In the semi-auto setting, at least one representative point of the plurality of trace points is set by the user, and the trace line forming unit 42 sets the remaining plurality of trace points based on the at least one representative point set by the user. .. A user such as a doctor or an inspection technician operates the operation device 60 while confirming the display image displayed on the display unit 52, determines a reference frame from a plurality of frames, and determines the reference frame in the image of the reference frame. The position of each representative point is designated and at least one representative point is set on the contour of the site to be diagnosed. For example, if the site to be diagnosed is the left ventricle, three representative points corresponding to three positions of two annulus portions and one apex of the heart are set.

In the full auto setting, the trace line forming unit 42 sets all of the plurality of trace points. The trace line forming unit 42 first determines a reference frame from a plurality of frames. For example, the first frame (the frame in the earliest time phase) of the plurality of frames to be diagnosed is set as the reference frame. Of course, a frame corresponding to the end systole or end diastole determined from the electrocardiographic waveform information, or a user-specified time phase frame may be used as the reference frame.

Then, in the full auto setting, the trace line forming unit 42 analyzes the image in the cross section of the reference frame to extract the contour of the diagnosis target portion included in the image (cross section). For the contour extraction, for example, pattern matching, an active contour model (ACM), a dynamic shape model (ASM) using machine learning, a dynamic appearance model (AAM), or the like can be applied. In the extraction of the contour, for example, two valve annulus portions having relatively high brightness in the image are extracted as representative points, and the apex specified by the positions of the two valve annulus portions is used as a representative point. It is desirable to set a plurality of trace points based on the representative points. In extracting the representative points, a learning method such as the AdaBoost method may be used. In this way, for example, when the site to be diagnosed is the left ventricle, a plurality of trace points are set on the boundary of the endocardium of the left ventricle.

The trace line processing unit 40 has a function of correcting the trace line formed by the trace line forming unit 42. The correction of the trace line is executed by the selection point movement processing unit 44, the tracking target determination unit 46, and the tracking processing unit 48.

In the correction of the trace line, a selected trace point is selected by a user such as a doctor or an inspection technician from a plurality of trace points forming the trace line. The user operates the operation device 60 while looking at the display image of the trace line displayed on the display unit 52, for example, the tomographic image shown in FIG. 2, and selects one trace point whose position is to be corrected from the plurality of trace points. Select as a trace point. For example, a pointer is displayed in the display image, and the user operates the operation device 60 to move the pointer to or near one trace point whose position is desired to be corrected and perform a selection operation to select the selected trace point. It

When the selected trace point is selected, the selected point movement processing unit 44 moves the selected trace point. The selected point movement processing unit 44 moves the selected trace point in the movement amount and the movement direction according to the instruction from the user. For example, a pointer is displayed in the display image, and the user uses the operation device 60 to perform a drag operation on the selected trace point designated by the pointer, thereby determining the moving direction and the moving amount of the selected trace point.

When the selected trace point moves, the following trace points located near the selected trace point also follow. The tracking trace point is determined by the tracking target determination unit 46. The follow-up target determination unit 46 determines a follow-up trace point within the target range of the follow-up process with the selected trace point as the base point, from the plurality of trace points forming the trace line.

The target range of the tracking process is near the selected trace point, and the larger the moving amount of the selected trace point is, the wider the target range is set. Further, the movement amount becomes smaller as the tracing point is farther from the selected tracing point. The target range and the movement amount of the tracking process are determined by using, for example, the Gaussian function of the following equation.

In Equation 1, X ₀ is the position of the selected trace point (coordinates before movement), X _n is the position of the n-th (n is a natural number) trace point (coordinates before movement), and c is the selected trace. It is the amount of movement of the point and is a variable that determines the spread of the Gaussian function, and the sensitivity is adjusted by the parameter a. The movement amount ratio Rn for the n-th trace point is calculated by the equation (1).

FIG. 3 is a diagram showing a specific example of the target range of the tracking process and the movement amount. FIG. 3 shows the result of the target range and the movement amount obtained by using the Gaussian function of the equation (1). In FIG. 3, the horizontal axis is the distance from the selected trace point (selection point) to the following trace point (neighbor point), and the vertical axis is the moving amount ratio Rn of the following trace point to the moving amount of the selected trace point (selected point). Is shown. FIG. 3 shows each function curve when ac=1, 5, 10, 20 in the equation (1).

According to the specific example of FIG. 3, the moving amount ratio Rn gradually decreases as the distance from the selected trace point increases. The moving amount (following amount) of the following trace point is determined by multiplying the moving amount of the selected trace point by the moving amount ratio Rn. Therefore, as the distance from the selected trace point increases, the movement amount of the following trace point decreases.

Further, in the specific example of FIG. 3, if the parameter a has a constant value, the skirt of the function curve becomes wider as the movement amount c of the selected trace point becomes larger. That is, the larger the movement amount c of the selected trace point, the wider the target range of the following trace point. For example, in the specific example of FIG. 3, the movement amount may be regarded as 0 (zero) when the movement amount ratio Rn is below the lower limit threshold Th. As a result, the range of the neighboring points corresponding to the movement amount ratio Rn exceeding the lower limit threshold Th on the vertical axis becomes the target range of the follow-up trace points.

Further, even if the movement amount c of the selected trace points is the same, the larger the parameter a, the wider the target range of the following trace points. The parameter a may be a fixed value determined in advance, but for example, it is desirable that the user can appropriately adjust the size of the parameter a. By the way, when the parameter a is 0 (zero), the target range disappears, and only the selected trace point becomes the target of movement.

Although a specific example using the Gaussian function has been described, if the function is a monotonically decreasing function that becomes smaller as it gets farther from the selected trace point, a function other than the Gaussian function (exponential function, trigonometric function, etc.) is used to perform the tracking process. The target range and the movement amount may be determined.

Further, the follow-up target determination unit 46 determines the follow-up trace point according to the constraint condition that the feature trace point corresponding to the feature point of the organization is not the target of the follow-up processing. For example, when the site to be diagnosed is the left ventricle and a plurality of trace points are set on the boundary of the intima of the left ventricle, the three features of the two valve annulus portions and one apex are characteristic of the tissue. It becomes a point. That is, the three trace points corresponding to the two annulus portions and one apex are set as the characteristic trace points.

When the trace points other than the characteristic trace points are selected as the selected trace points, the following target determination unit 46 determines the following trace points so that the characteristic trace points are not included. When the characteristic trace point is selected as the selected trace point, the follow-up trace point is determined so that the characteristic trace points other than the selected trace point are not included. Further, when setting the target range extending from the selected trace point side to the characteristic trace point side, the tracking target determination unit 46 sets the target range so as not to exceed the characteristic trace point.

FIG. 4 is a diagram for explaining the setting pattern of the target range. When setting the target range extending from the selected trace point side to the characteristic trace point side, the tracking target determination unit 46 sets the target range so as not to exceed the characteristic trace points according to a plurality of setting patterns shown in FIG. 4, for example.

FIG. 4 shows a specific example of the setting patterns from pattern 1 to pattern 3. Note that, in FIG. 4, a plurality of trace points (circles) forming the trace line of the left ventricular membrane are illustrated for each pattern, and the selected trace points are displayed as black circles (filled circles). The area indicated by the broken line is the target range.

Patterns 1(a) and (c) are cases in which the characteristic trace points corresponding to the annulus are selected as the selected trace points. In this case, since the characteristic trace point corresponding to the annulus is the selected trace point, it is the target of the movement processing by the selection point movement processing unit 44. Then, the target range is set so as to include the feature trace points corresponding to the annulus portion which is the selected trace point and do not exceed the feature trace points corresponding to the apex.

Pattern 2(b) is a case where the characteristic trace point corresponding to the apex is selected as the selected trace point. In this case, since the characteristic trace point corresponding to the apex is the selected trace point, it is targeted for the movement processing by the selection point movement processing unit 44. Then, the target range is set so as to include the characteristic trace points corresponding to the apex, which is the selected trace point, and do not exceed the characteristic trace points corresponding to the annulus.

Patterns 3(d) and (e) are cases where the trace points other than the characteristic trace points are selected as the selected trace points. The selected trace points are subjected to the movement processing by the selection point movement processing unit 44. Then, the target range is set so as not to exceed the feature trace point corresponding to the valve annulus and the feature trace point corresponding to the apex, including the selected trace point.

In this way, the target range is set so as not to exceed the characteristic trace points according to a plurality of setting patterns shown in FIG. 4, for example. Then, for example, the specific example shown in FIG. 3 is applied to each pattern, and the amount of movement regarding the width of the target range and the following trace points within the target range is determined.

FIG. 5 is a flowchart showing a specific example of the processing until the movement amount of the tracing trace point is determined. When a selected trace point (selected point) is selected from a plurality of trace points that form a trace line, the distance from the selected trace point to each trace point is calculated (S501), and each trace is calculated by, for example, Equation 1. The moving amount ratio of the points is calculated (S502).

Next, it is confirmed whether or not the trace point corresponding to the apex of the plurality of trace points constituting the trace line is designated (S503). For example, the user may specify the trace point corresponding to the apex, or the trace line processing unit 40 may specify the trace point corresponding to the apex based on the positions of the two valve annulus portions, for example.

Then, if the trace point corresponding to the apex is not designated, the movement amounts of all trace points other than the selected trace point are calculated (S504). That is, if the trace point corresponding to the apex is not designated, there is no constraint condition regarding the feature trace point, and all trace points become candidates for the trace processing, and the trace trace points are determined in the vicinity of the selected trace points.

On the other hand, when the trace point corresponding to the apex is designated, the three trace points corresponding to the apex and the two annulus portions are the characteristic trace points, and the selected trace points (selection points) The movement amount of the following trace point is determined according to the pattern according to the position (S505, see FIG. 4).

That is, when the left annulus (the annulus on the left side in the tomographic image) is selected as the selected trace point, a plurality of trace points on the left side of the apex become candidates for the tracking process (Fig. 4(a)), the movement amount of the following trace points corresponding to the movement amount ratio (see FIG. 3) exceeding the lower limit threshold is calculated from the plurality of trace points (S506a). In this case, the amount of movement of the trace point corresponding to the apex is set to 0 (zero).

When the right annulus (the annulus on the right side in the tomographic image) is selected as the selected trace point, a plurality of trace points on the right side of the apex are candidates for tracking processing (see FIG. of the plurality of trace points, the movement amount of the following trace point corresponding to the movement amount ratio (see FIG. 3) exceeding the lower limit threshold value is calculated (S506c). Also in this case, the movement amount of the trace point corresponding to the apex is set to 0 (zero).

If a trace point between the apex and the left valve annulus is selected as the selected trace point, a plurality of trace points between the apex and the left valve annulus become candidates for the tracking process ( 4E), the movement amount of the following trace points corresponding to the movement amount ratio (see FIG. 3) exceeding the lower limit threshold is calculated from the plurality of trace points (S506e). In this case, the amount of movement of the trace point corresponding to the apex and the trace point corresponding to the left annulus is set to 0 (zero).

When a trace point between the apex and the right valve annulus is selected as the selected trace point, a plurality of trace points between the apex and the right valve annulus are candidates for the tracking process (see FIG. 4). (See (d)), of the plurality of trace points, for example, the movement amount of the following trace point corresponding to the movement amount ratio (see FIG. 3) exceeding the lower limit threshold value is calculated (S506d). In this case, the amount of movement of the trace point corresponding to the apex and the trace point corresponding to the right annulus is set to 0 (zero).

When the apex is selected as the selected trace point, a plurality of trace points between the apex and each annulus (the left annulus and the right annulus) are candidates for the tracking process (see FIG. 4). (See (b)), of the plurality of trace points, for example, the movement amount of the following trace point corresponding to the movement amount ratio (see FIG. 3) exceeding the lower limit threshold is calculated (S506b). In this case, the amount of movement of the trace points corresponding to the left valve annulus and the trace points corresponding to the right valve annulus is 0 (zero).

When the selected trace point is selected and the following trace point and its movement amount are determined, the following processing unit 48 moves the following trace point so as to follow the movement of the selected trace point. The tracking processing unit 48 translates the tracking trace points in the same direction as the moving direction of the selected trace points, for example. The tracking processing unit 48 moves the tracking trace point so as to follow the movement of the selected trace point while fixing the characteristic trace point.

FIG. 6 is a diagram showing a specific example 1 of correction of a trace line. In FIG. 6, a plurality of circles lined up along a broken line which is a trace line are a plurality of trace points. Further, FIG. 6 shows a characteristic trace point LP corresponding to the left annulus, a characteristic trace point RP corresponding to the right annulus, and a characteristic trace point AP corresponding to the apex of the heart. The dots are shown as black circles (filled circles).

FIG. 6(0) shows a trace line before correction formed by the trace line forming unit 42. A specific example of the correction process for a plurality of trace points forming the trace line shown in FIG. 6(0) is shown in FIGS. 6(1) and 6(2).

FIG. 6A shows a specific example of the follow-up process when the movement amount of the selected trace point is small. When the movement amount of the selected trace point is small, the target range of the following trace point is narrow and the moving amount of the following trace point is also small.

On the other hand, FIG. 6B shows a specific example of the follow-up process when the movement amount of the selected trace point is large. When the movement amount of the selected trace point is large, the target range of the follow-up trace point is wider and the movement amount of the follow-up trace point is larger than that in the case of FIG. 6A where the movement amount is small.

In either case of FIGS. 6A and 6B, it is desirable that the moving direction of the following trace point is the same as the moving direction of the selected trace point. Then, a corrected trace line is formed based on the plurality of trace lines after the tracking process.

FIG. 7 is a diagram showing a specific example 2 of correction of trace lines. In FIG. 7, a plurality of circles arranged along a broken line which is a trace line are a plurality of trace points. Further, FIG. 7 shows a characteristic trace point LP corresponding to the left annulus, a characteristic trace point RP corresponding to the right annulus, and a characteristic trace point AP corresponding to the apex of the heart, and a selected trace. The dots are shown as black circles (filled circles).

FIG. 7(1) shows a specific example of the follow-up process when the characteristic trace point RP corresponding to the right valve annulus is the selected trace point. In this case, a plurality of trace points on the right side of the characteristic trace point AP corresponding to the apex become candidates for the tracking process (see FIG. 4C), and among the plurality of trace points, the selected trace point is selected. Following trace points are determined in the vicinity. The larger the movement amount of the selected trace point, the wider the target range of the following trace point. The characteristic trace point LP corresponding to the left valve annulus is in the vicinity of the selected trace point, but is fixed and is not the object of follow-up movement. As a result, it is possible to perform follow-up processing targeting the vicinity of the selected trace point while respecting the initial position of the characteristic trace point LP.

FIG. 7B shows a specific example of the tracking process when the characteristic trace point AP corresponding to the apex is set as the selected trace point. In this case, a plurality of trace points between the apex and each annulus (the left annulus and the right annulus) are candidates for the tracking process (see FIG. 4B), and the plurality of traces are traced. Among the points, the following trace point is determined in the vicinity of the selected trace point. The larger the movement amount of the selected trace point, the wider the target range of the following trace point. The characteristic trace point LP corresponding to the left annulus and the characteristic trace point RP corresponding to the right annulus are fixed and are not moved.

FIG. 7C shows a specific example of the follow-up process when the trace point between the characteristic trace point AP corresponding to the apex and the characteristic trace point RP corresponding to the right annulus is set as the selected trace point. There is. In this case, the plurality of trace points between the apex and the right valve annulus become candidates for the tracking process (see FIG. 4D), and the trace is performed in the vicinity of the selected trace point among the plurality of trace points. The trace points are determined. The characteristic trace point AP corresponding to the apex is fixed although it is in the vicinity of the selected trace point, and is not the object of follow-up movement. As a result, it is possible to perform follow-up processing targeting the vicinity of the selected trace point while respecting the initial position of the characteristic trace point AP.

Also in the specific example of FIG. 7, it is desirable that the moving direction of the following trace point is the same as the moving direction of the selected trace point. Then, a corrected trace line is formed based on the plurality of trace lines after the tracking process. As a result, it becomes possible to make corrections in the vicinity of the selected trace point while respecting the initial position of the characteristic trace point. Of course, by selecting the characteristic trace point as the selected trace point, it becomes possible to modify the characteristic trace point and its neighborhood.

Although the preferred embodiments of the present invention have been described above, the above-described embodiments are merely examples in all respects and do not limit the scope of the present invention. The present invention includes various modifications without departing from the essence thereof.

10 probe, 12 transmitting/receiving unit, 20 image forming unit, 22 image storing unit, 30 image selecting unit, 40 trace line processing unit, 42 trace line forming unit, 44 selected point moving processing unit, 46 tracking target determining unit, 48 tracking processing Section, 50 display processing section, 52 display section, 60 operating device, 100 control section.

Claims (4)

A movement processing unit that moves a selected trace point among a plurality of trace points that form a trace line of tissue in an ultrasonic image,
From the plurality of trace points, a constraint condition that does not make a plurality of feature trace points corresponding to a plurality of feature points of the tissue a target of the follow-up process and the target range of the follow-up process that is based on the selected trace point is selected. According to a target range condition in which the larger the moving amount of the trace point is, the following target determination section that determines the following trace point within the target range of the tracking process with the selected trace point as a base point,
A tracking processing unit that moves the tracking trace points so as to follow the movement of the selected trace points,
Have a,
When the selected trace point is a specific feature trace point, another feature trace point is not subject to the tracking process according to the constraint condition, and the movement amount of the specific feature trace point is according to the target range condition. The larger is, the wider the target range is,
An ultrasonic diagnostic apparatus characterized by the above. The ultrasonic diagnostic apparatus according to claim 1 ,
The tracking processing unit determines the amount of movement of the tracking trace point based on the amount of movement of the selected trace point and the distance from the selected trace point to the tracking trace point,
An ultrasonic diagnostic apparatus characterized by the above. The ultrasonic diagnostic apparatus according to claim 1 ,
The tracking processing unit translates the tracking trace point in the same direction as the moving direction of the selected trace point,
An ultrasonic diagnostic apparatus characterized by the above. The ultrasonic diagnostic apparatus according to claim 1 ,
Wherein the plurality of feature trace points, among the plurality of trace points forming the heart chamber of the trace line is a trace line of the tissues, two traces corresponding to the trace point corresponding to the apex and two annulus Is a point ,
An ultrasonic diagnostic apparatus characterized by the above.