JPH08625A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To calculate a contour point of internal organs with high accuracy by making respective brightness informations at expanding time from contracting time of the internal organs almost coincide at a brightness point with selected brightness information when an A mode extracting line crossing the internal organs is designated on a display surface on which a tomographic image containing the interal organis such as the heart is displayed. CONSTITUTION:A tomographic image containing the heart 20 is displayed on a display surface 6A of a display device 6 in an ultrasonic diagnostic device together with an A mode extracting line 30. Respective image data changing according to a movement of the heart 20 are outputted to a control operation graphic part 8, and here, present time picture element data and previous picture element data are compared with each other, and the ratio obtained by the comparison is stored in a memory 12 as a correction value. Next, respective picture element data normalized by a data converting part 13 are inputted to a brightness inclination operation circuit 16 through a smoothing circuit 14 and a shift register 15, and a place approaching the cardiac cavity side at a specific rate from a part of a cardiac muscle having a maximum brightness value is judged as a boundary point on the cardiac cavity side of the cardiac muscle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an image diagnostic apparatus equipped with means for extracting the contour of a displayed tomographic organ.

[0002]

2. Description of the Related Art For example, in an ultrasonic diagnostic apparatus, when a so-called A mode extraction line is designated and displayed so as to cross the heart on the still image plane of the heart displayed on its display (CRT), the A mode extraction is performed. A contour point of the heart, for example, a boundary point on the heart chamber side of the myocardium is calculated from the brightness information along the line, and changes in the movement of the heart and the like can be accurately grasped based on the boundary point.

Further, by calculating such boundary points, it becomes possible to approximately calculate the volume of the heart chamber of the heart.

Conventionally, in the case of calculating such a boundary point, from the luminance information along the A-mode extraction line, the point from the point with the lowest luminance value to the maximum point is detected, and the point is fixed from the maximum point. The point having the brightness value having the brightness value subtracted by the ratio is calculated.

That is, it is based on the empirical rule that the portion of the myocardium having the maximum brightness value that is close to the heart chamber at a constant rate is the boundary point on the heart chamber side of the myocardium.

[0006]

However, in recent years,
It is desired to extract the contour points of the heart in real time only by designating and displaying the A-mode extraction line so as to traverse the heart on the display surface in which the heart is repeatedly contracting and expanding. Came to.

By being able to do in this way, it is possible to grasp the accurate movement of the heart and the like, and to bring about a diagnostic effect.

However, since the brightness information along the A-mode extraction line changes sequentially at each time when the heart repeats its contraction and expansion, for example, it is constant from the part of the myocardium having the maximum brightness value. The problem that the above-mentioned idea that the part close to the side of the heart chamber is the boundary point of the myocardium on the side of the heart chamber cannot be uniformly applied as it is.

Therefore, the present invention has been made under such circumstances, and an object thereof is an organ which operates by repeatedly contracting and expanding from luminance information along the A-mode extraction line. Another object of the present invention is to provide an ultrasonic diagnostic apparatus capable of easily and accurately calculating contour points in each morphological change.

[0010]

In order to achieve such an object, the present invention basically provides a display surface on which a tomographic image including an organ that repeatedly contracts and expands is displayed. A-mode extraction line designating means for designating an A-mode extraction line so as to traverse, and luminance information along the A-mode extraction line designated by the A-mode extraction line designating means at the time of contraction and expansion of the organ. The luminance information extracting means for extracting each of the luminance information and the luminance standardization for making the luminance information from the contraction time to the expansion time extracted from the luminance information extraction means substantially coincide with the selected luminance information in terms of luminance. And a contour calculator for calculating the contour points of the organ from the respective luminance information at the time of contraction and at the time of expansion obtained from the luminance normalizing means. When, it is characterized in that it comprises a.

[0011]

According to the ultrasonic diagnostic apparatus having such a configuration, the brightness information along the designated A-mode extraction line across the organ is extracted even when the organ contracts and expands. The luminance information on one side is matched with the luminance information on the other side in terms of luminance.

That is, the brightness that relatively changes in the process of organ movement is corrected as if it did not change.

On the basis of the corrected brightness information, for example, a portion close to the heart chamber side at a constant rate from the part of the myocardium having the maximum brightness value is a boundary point (contour) on the heart chamber side of the myocardium. Point).

Therefore, such a determination can be performed uniformly, that is, easily even when the organ is contracted and expanded, and the contour points can be accurately calculated.

[0015]

1 is a block diagram showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention.

In the figure, first, there is an ultrasonic probe 1 which is used by being brought into contact with a subject. This ultrasonic probe 1
Is composed of, for example, a so-called sector scanning probe in which an ultrasonic beam is scanned in a fan shape with the probe as an apex.

Here, in the case of this embodiment, for example, a case of obtaining a tomographic image including the heart will be described. Therefore, the ultrasonic probe 1 is used by being brought into contact with the body surface in the vicinity of the heart. .

The ultrasonic probe 1 can transmit ultrasonic waves into the subject by driving the ultrasonic transmitter / receiver 2.
Ultrasonic information, which is the reflected wave (echo), is captured and input to the ultrasonic transceiver 2.

The ultrasonic wave information captured by the ultrasonic wave transmitter / receiver 2 is digitized by an A / D converter in the ultrasonic wave transmitter / receiver 2 and then input to the cine memory 3.

The cine memory 3 sequentially stores reflection echo information (US line data) for each ultrasonic beam from the ultrasonic probe 1 and repeats this for each frame. Therefore, when the electrocardiographic waveform diagram is also displayed based on the output from the EGS electrode 18 described later, the time correspondence can be taken, and the information corresponding to the time is output to the electrocardiographic unit 19. It has become so.

This memory also has a buffer function for output to the digital scan converter 4 connected to the next stage.

The digital scan converter 4 writes the ultrasonic wave information from the cine memory 3 into a built-in line memory for each scanning line or plural scanning lines of the ultrasonic beam to form a tomographic image (B mode) image data. It is like this.

Further, the image data from the digital scan converter 4 is input to a display device 6 such as a CRT via a synthesizing circuit 5, and a tomographic image including the heart is displayed on the display surface of the display device 6. It is like this.

In this case, as shown in FIG.
A tomographic image including the heart 20 is imaged on the display surface 6A, and the A mode extraction line 30 can be designated to be drawn on the image surface as shown in FIG.

The designation of the A-mode extraction line 30 can be performed by the input unit 7 which is operated by, for example, operating the trackball. For example, the start point and the end point of the A mode extraction line 30 to be designated by scanning the trackball are designated, and the mode for connecting these points is designated.

Information of such an operation in the input section 7 is inputted to the writing / reading circuit 9A in the reflection intensity change detecting section 9 which will be described later in detail through the control arithmetic graphic circuit 8.

Information specified by the A-mode extraction line 30 from the input unit 7 is displayed as specified on the tomographic image displayed on the display device 6 via the graphic display unit 10 and the synthesis circuit 5. It has become.

In this case, the A-mode extraction line 30 thus displayed is displayed at a fixed position with respect to the display surface 6A, but the heart 20 in the tomographic image is repeatedly contracted and expanded to form an image. Has been done.

On the other hand, the ultrasonic wave data from the cine memory 3 is input to the frame memory 11 of the reflection intensity change detecting section 9.

Here, the frame memory 11 is composed of two frame memories 11A and 11B, and after the ultrasonic data for one scan is input to the frame memory 11A, the ultrasonic data for the next one scan is framed. The operation of inputting to the memory 11B and further ultrasonic data for the next one scan to the frame memory 11A is repeated.

The frame memory 11 for each such input
Writing to A and 11B is performed by the write / read control circuit 9A.

Then, the writing / reading control circuit 9A reads out the pixel data along the direction of the A-mode extraction line 30 based on the information of the A-mode extraction line 30 inputted from the input section 7. It has become so. That is, the pixel data of each of the frame memories 11A and 11B is read based on the address that determines the A mode extraction line 30.

The pixel data read from each of the frame memories 11A and 11B as described above is sent to the multiplexer 9B.
Pixel data along the A-mode extraction line 30 for each ultrasonic data in each scan is sequentially output by the multiplexer 9B.

FIG. 3 shows pixel data 4 obtained along the A mode extraction line 30 for each ultrasonic data in each scan.
0 is shown. It is found that this pixel data has high brightness in the part of the myocardium and is low in other parts.

Here, the pixel data 40 along the A-mode extraction line 30 follows the movement of the heart 20, and in the process in which the heart 20 moves from expansion (solid line) to contraction (dotted line). It is designed to change from (a) to (b) in the figure. Here, the width of the high-intensity part indicating the part of the myocardium changes according to the movement of the heart, and the brightness of each high-intensity part changes.

The pixel data that changes in accordance with the movement of the heart 20 in this way is stored in the control calculation graphic unit 8
In the control calculation graphic unit 8, for example, the pixel data input at the present time is compared with the pixel data input at a previous time point (comparison of brightness), the ratio is calculated, and the calculation is performed. The value is stored as a correction value in the correction value memory 12.

In this way, the correction value memory 12 stores
Correction values according to each pixel data will be stored,
The respective correction values are sequentially output to the data conversion unit 13.

On the other hand, the pixel data read from the digital scan converter 4 based on the preset address on the A-mode extraction line 30 is supplied to the data converter 13 in accordance with the movement of the heart. Corresponding correction values from the correction value memory 12 that are input and that are input at the same time are sequentially multiplied.

As a result, the pixel data on the A-mode extraction line extracted from the heart at the time of contraction is shown in FIG.
4B, the pixel data on the A-mode extraction line converted from that shown in FIG. 4B and extracted from the heart at the time of expansion is as shown in FIG. 5A. If so, the conversion is performed as shown in FIG. 5 (b). In this case,
As shown in (b) and FIG. 5 (b), the luminance values h of the high-luminance portions of the converted pixel data become equal to each other, and so-called normalization is performed.

The normalized pixel data are sequentially input to the smoothing circuit 14, and the smoothing circuit 14 smoothes the pixel data along a line segment.

As a smoothing method in this case, for example,
As shown in FIG. 6, the highest parts of the respective edges of the waveform are connected. As another method, the lowest part of each edge of the waveform may be connected, the middle of the highest part and the lowest part of each edge may be connected, or the so-called moving average processing method may be used. It goes without saying that there is a method such as the above, and any of these may be applied.

Further, the pixel data thus smoothed is input to the shift register 15.

The shift register 15 is a primary storage device that sequentially holds the input pixel data for, for example, 5 addresses.

This means that the smoothed pixel data shown in FIG. 6 are sequentially stored with luminance values (peak values) of 5 pixels each from the right side to the left side in the figure, and the luminance values are collectively and sequentially processed. It is adapted to be input to the brightness gradient calculating circuit 16.

The brightness gradient calculating circuit 16 detects the degree of change with time from the five input brightness values, whereby the maximum value in the waveform of FIG. 7, that is, from monotonous increase to monotonous decrease. The value of the change point of is calculated.

In this case, the maximum values P ₁ and P ₂ are detected in the waveform shown in FIG. Then, a luminance value Q _{1 obtained} by subtracting a constant ratio a / h (a value based on an empirical rule, for example, 95%) from the luminance value at the maximum values P ₁ and P ₂ ,
The addresses of Q ₂ are detected, and the information of these addresses is input to the control calculation graphic unit 8.

The addresses of the brightness values Q ₁ and Q ₂ in this case are the A mode extraction line 30 of the heart 20 in FIG.
It corresponds to the points of contour points C ₁ and C ₂ which are the septums of the myocardium and the heart chamber in.

By doing so, the brightness on the A-mode extraction line 20 that changes relatively in the course of the movement of the heart 20 is corrected as if it did not change.

Then, based on this corrected luminance information, for example, a portion close to the heart chamber side at a constant rate from the portion of the myocardium having the maximum luminance value is the boundary point (outline of the heart chamber side of the myocardium). Point).

Therefore, such a determination can be performed uniformly, that is, easily even when the organ is contracted and expanded, and an accurate contour point can be calculated.

Then, in the control calculation graphic unit 8, as shown in FIG. 8, a graph of the change in movement of Q _{1 with} the passage of time of the heart 20 on the right side of the sectional image on the display surface 6A of the display device 6 is shown. A graph β of changes in movement of α and Q ₂ with time is created. By observing the graphs α and β, it becomes possible to easily recognize the separation and proximity of the contour points C ₁ and C ₂ with the passage of time.

The graphs α, β are displayed on the display surface 6A.
The electrocardiographic waveform 40 corresponding to the time axis of is displayed. The electrocardiographic waveform 40 is created as follows.

That is, the signals from the EGS electrodes which are used in contact with the subject at the same time are input to the control calculation graphic unit 8 via the electrocardiographic unit 19.
On the other hand, the control calculation graphic unit 8 takes in information of, for example, beam scanning time (and by extension, time indicating the movement of the heart) that can be detected from the cine memory 3, and creates an electrocardiographic waveform diagram 40 corresponding to this time information. It is like this.

As described above, by displaying the graphs α and β in association with the electrocardiographic waveform diagram 40 in time, it is possible to obtain an effect that the graphs α and β can be accurately determined from their relationship. .

In FIG. 8, the waveform indicated by the reference numeral 50 is the A-mode extraction line 3 displayed as in the conventional case.
It is a waveform showing the luminance on 0, and the luminance is displayed so as to change according to the movement of the heart.

According to the ultrasonic diagnostic apparatus of the above-described embodiment, the brightness information along the designated A-mode extraction line across the heart is extracted even when the heart contracts and expands, The brightness information of one of them is made to substantially match the brightness information of the other in terms of brightness.

That is, the brightness that relatively changes in the course of the movement of the heart is corrected as if it did not change.

Then, based on the corrected brightness information, for example, a portion close to the heart chamber side at a constant rate from the part of the myocardium having the maximum brightness value is the boundary point (outline of the heart chamber side of the myocardium). Point).

Therefore, such a determination can be performed uniformly, that is, easily even when the heart is contracting and expanding, and an accurate contour point can be calculated.

In the above-described embodiment, both the contour points O ₁ and O ₂ on the A mode extraction line 30 are displayed in the form of a graph. However, the present invention is not limited to this, and only one of them is displayed. It goes without saying that it is good. Further, it is needless to say that the invention is not limited to the boundary between the contour point, the myocardium, and the heart chamber, and can be applied to other boundary.

Furthermore, in the above-described embodiment, the description has been made for the heart, but the present invention is not limited to this, and the same effect can be obtained even if the target is a cross section of a blood vessel. be able to. The point is that the same effect can be achieved by targeting an organ that operates by repeating contraction and expansion.

[0062]

As is apparent from the above description,
According to the image diagnostic apparatus of the present invention, it is possible to easily and accurately calculate contour points in each morphological change of an organ that operates by repeating contraction and expansion from luminance information along an A-mode extraction line. become.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention.

FIG. 2 is an explanatory diagram showing an example of setting an A mode extraction line on a display surface of a display device.

FIG. 3 is an explanatory diagram for explaining pixel data along an A mode extraction line.

FIG. 4 is an explanatory diagram showing an example of normalization of pixel data along an A-mode extraction line when the heart contracts.

FIG. 5 is an explanatory diagram showing an example of normalization of pixel data along an A-mode extraction line when the heart is enlarged.

FIG. 6 is an explanatory diagram showing an example of smoothing of pixel data along an A-mode extraction line.

FIG. 7 is an explanatory diagram showing an example of determining a contour point from pixel data along an A-mode extraction line.

FIG. 8 is an explanatory diagram showing an example of a screen displayed on a display device when the present invention is applied.

[Explanation of symbols]

 9 ………… Reflection intensity change detector 12 ………… Correction value memory 13 ………… Data converter

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hiroshi Kanda 1-1-14 Kanda, Chiyoda-ku, Tokyo Inside Hitachi Medical Co., Ltd.

Claims (1)

[Claims] 1. An A-mode extraction line designating unit for designating an A-mode extraction line so as to traverse the organ on a display surface on which a tomographic image including an organ that repeatedly contracts and expands is displayed, and the A-mode. A designated by the extraction line designating means
Luminance information extracting means for extracting the luminance information along the mode extraction line at the time of contraction and expansion of the organ, and the luminance information at the time of contraction to expansion that is extracted from the brightness information extraction means The brightness normalizing means for making the selected brightness information substantially coincide with the brightness information, and the contour points of the organ are calculated from the brightness information at the time of contraction and at the time of expansion obtained from the brightness normalizing means. An image diagnostic apparatus comprising: