JPH087074A - Method and device for displaying image and image diagnostic device - Google Patents

Abstract

PURPOSE:To easily and correctly recognize the upper limit value and lower limit value of a picture element value in a region of interest. CONSTITUTION:The range of a CT value is divided into two parts being a background part(except for G2) and a region of interest part G2. The luminance gradation of a display monitor is device into two parts being a low luminance part L and a high luminance part U. Then, the CT value of the backgraound part (except for G2) is converted into the luminance value of the low luminance part L by a background window B, the CT value of the region of interest part G2 is converted into the luminance value of the high luminance part U by a highlight window H and the image is displayed. Moreover, an operator is permitted to be able to optionally change the width of the highlight window H and a center position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display method, an image display device, and an image diagnostic device, and more particularly, it is possible to display a background with low brightness and a region of interest with high brightness to improve usability. The present invention relates to an image display method, an image display device, and an image diagnostic device.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional X-ray CT (Computed To
1 is a block diagram of an example of a mography device. The X-ray CT apparatus 500 includes a scanner device 1, a processing device 52, a display monitor 3, and an operating device 54. The scanner device 1 scans the patient K and collects scan data. The processing device 52 generates a scan image having CT values as pixel values from the scan data. The operator operates the operation device 54 to input the window width WW and the center position (window level) WL. Then, the window setting unit 52a of the processing device 52 sets the window W having the window width WW and the center position WL as shown in FIG. The range of the brightness value is the range of the brightness gradation (for example, 0 to 255) of the display monitor 3.
The window W may be, for example, a LUT (Look Up
Table) or calculation formula.

The window processing section 52d of the processing unit 52
As shown in (a) of FIG. 7, using the window W, the CT value of the scan image (CT value of air G0, tissue G1
Value of tissue, CT value of tissue G2 and CT value of tissue G3)
To a brightness value. Then, based on the brightness value,
As shown in FIG. 7B, the image is displayed on the display monitor 3.

FIG. 8 is a flow chart of an operation procedure performed by an operator using the conventional X-ray CT apparatus 500 in order to know the lower limit value and the upper limit value of the CT value in the region of interest.
For convenience of explanation, the tissue G2 is assumed as the region of interest. In step B1, the operator operates the window width change button 54b and the window level change button 54c of the operation device 54 to reduce the width WW of the window W to the minimum as shown in FIG. , The center position WL is lowered to the minimum. Then, the screen of the display monitor 3 becomes pure white as shown in FIG. In addition,
The window processor 52d of the processor 52 displays the center position WL (= w0) of the window W on the screen of the display monitor 3.

In steps B2 and B3, the operator operates the window level change button 54c to raise the center position WL of the window W until the tissue G2 starts to be seen.
At the time when the tissue G2 starts to be seen, as shown in FIG. 10A, the center position WL of the window W is CT of the tissue G2.
The lower limit of the value is met. Further, on the screen of the display monitor 3, as shown in FIG. 10B, the air G0 and the tissue G1 are black, the tissue G2 is partially visible, and the tissue G3 is white. In step B4, the operator recognizes the center position WL (= w1) of the window W when the tissue G2 starts to be seen as the lower limit value of the CT value of the tissue G2.

In steps B5 and B6, the operator operates the window level change button 54c to raise the center position WL of the window W until the tissue G2 is no longer visible. At the time when the tissue G2 has just disappeared, FIG.
As shown in 1 (a), the center position WL of the window W
Matches the upper limit of the CT value of the tissue G2. In addition, as shown in FIG. 11B, the screen of the display monitor 3 becomes black in the air G0, the tissue G1, and the tissue G2, and becomes white in the tissue G3. In step B7, the operator recognizes the center position WL (= w2) of the window W when the tissue G2 is just out of sight as the upper limit of the CT value of the tissue G2.

[0007]

The above-mentioned X-ray CT apparatus 50
At 0, the operator remembers the region of interest in his head,
CT of the ROI is judged by judging "when the ROI starts to be visible" and "when the ROI has just disappeared".
It recognizes the upper and lower limits of the value. However, it is easy to judge "when the region of interest begins to be seen" and "when the region of interest has just disappeared" by observing a screen with only a part of intermediate luminance gradation and mostly black or white. However, there is a problem that it is likely to be inaccurate. Therefore, a first object of the present invention is to provide an image display method and an image display device which allow the user to see the entire image and also to clearly distinguish the background (non-region of interest) from the region of interest. And to provide an image diagnostic apparatus. A second object of the present invention is to provide an image diagnostic apparatus capable of easily and accurately knowing the upper limit value and the lower limit value of the pixel value of the region of interest.

[0008]

SUMMARY OF THE INVENTION In a first aspect, the present invention provides an image display method for performing window processing on a pixel value to convert it into a brightness value, and displaying an image on a display means based on the brightness value. , The pixel value range is divided into at least two parts, a background part and a region of interest, and the brightness gradation of the display means is divided into at least two parts, a low brightness part and a high brightness part. A background window that uses the low-luminance portion is assigned, a highlight window that uses the high-luminance portion is assigned to the region of interest, and the operator can change the width or center position of the highlight window. An image display method is provided.

According to a second aspect, the present invention provides an image display device for performing window processing on a pixel value to convert it into a luminance value and displaying an image on a display means based on the luminance value.
When the range of pixel values is divided into at least two parts, a background part and a region of interest, and the brightness gradation of the display means is divided into at least two parts, a low brightness part and a high brightness part, Background window processing means for converting a pixel value into a brightness value of the low brightness portion, highlight window processing means for converting a pixel value of the region of interest into a brightness value of the high brightness portion, and width of the highlight window Alternatively, an image display device is provided, which is provided with an operation unit for an operator to change the center position.

According to a third aspect of the present invention, the pixel value of a scan image obtained by scanning a subject is windowed to be converted into a brightness value, and an image is displayed on a display means based on the brightness value. In the image diagnostic apparatus described above, when the range of the pixel value is divided into at least two parts of a background part and a region of interest, and the brightness gradation of the display means is divided into at least two parts of a low brightness part and a high brightness part. In the background window processing means for converting the pixel value of the background portion into the luminance value of the low luminance portion, the highlight window processing means for converting the pixel value of the region of interest portion into the luminance value of the high luminance portion, There is provided an image diagnostic apparatus comprising: an operation unit for an operator to change the width or center position of the highlight window. It is preferable that the image diagnostic apparatus configured as described above further includes threshold acquisition means for acquiring the minimum value and the maximum value of the pixel values of the highlight window changed by the operator and displaying the acquired minimum and maximum pixel values on the display means.

[0011]

In the image display method, the image display device and the image diagnostic device of the present invention, the range of pixel values is divided into at least two parts, that is, the background part and the region of interest, and the brightness gradation of the display means is divided into the low brightness part. Divide into at least two parts of the high brightness part. Then, the pixel value of the background portion is converted into the luminance value of the low luminance portion by the background window, and the pixel value of the region of interest is converted into the luminance value of the high luminance portion by the highlight window. Furthermore, the operator can change the width or the center position of the highlight window to some extent. This allows
Although the display state is relatively low, the entire image can be seen. Therefore, the operator can easily change the width or center position of the highlight window so that the desired region of interest is displayed with high brightness. Then, after the change, the region of interest can be brightly emphasized and viewed in the relatively dark background. Further, it becomes possible to easily know the lower limit value and the upper limit value of the pixel value of the region of interest from the minimum value and the maximum value of the pixel value of the highlight window.

[0012]

The present invention will be described in more detail with reference to the embodiments shown in the drawings. The present invention is not limited to this. FIG. 1 is a configuration diagram of an X-ray CT apparatus 100 according to an embodiment of the present invention. This X-ray CT device 10
0 is a scanner device 1, a processing device 2, and a display monitor 3
And an operating device 4. The scanner device 1 scans the patient K and collects scan data. The processing device 2 generates a scan image having CT values as pixel values from the scan data. The operator operates the operating device 4
By operating the window selection button 4a, the normal window (W in FIG. 6) or the background window (B in FIG. 2) can be selected. The window width change button 4b and the window level change button 4c are enabled for the selected window. Further, independently of that, the highlight window selection button 4d can be operated to enable or disable the highlight window (H in FIG. 2). When the highlight window is activated, the highlight window width change button 4e and the highlight window level change button 4f are activated.

The normal window is the same as the conventional window W described in FIG. 6, and when this is selected, the normal window setting section 2a and the window processing section 2 of the processing device 2 are selected.
d has the same function as the window setting unit 52a and the window processing unit 52d in FIG. Therefore, the operation is the same as the conventional one.

As shown in FIG. 2, the background window B is
Using the low brightness part L of the brightness gradation of the display monitor 3, C
It is a window for converting a T value into a luminance value. According to the operation of the operator, the background window setting unit 2 of the processing device 2
b sets the width BW and the center position BL of the background window B. The highlight window H is a window for converting a CT value into a brightness value using the high brightness portion U of the brightness gradation of the display monitor 3. The highlight window setting unit 2c of the processing device 2 sets the width HW and the center position HL of the highlight window H according to the operation of the operator. In FIG. 2, the luminance gradation of the display monitor 3 is divided into two equal parts in the low-luminance portion L and the high-luminance portion U, and the luminance value of the highlight window H is calculated from the luminance value of the background window B for the same CT value. Also, it is increased by 1/2 of the full width of the brightness gradation of the display monitor 3.

The window processing unit 2d of the processing device 2 performs window processing using a normal window, a background window B and a highlight window H set in the form of, for example, an LUT or a calculation formula. At that time, the highlight window H is given priority over the normal window and the background window B. The window processing using the normal window and the background window B and the window processing using the highlight window H may be separately performed to generate images separately, and they may be superposed when displayed.

The threshold acquisition unit 2e of the processing device 2 acquires the minimum and maximum CT values of the highlight window H and displays them on the display monitor 3.

FIG. 3 is a flow chart of an operation procedure performed by the operator using the X-ray CT apparatus 100 in order to know the lower limit value and the upper limit value of the CT value of the region of interest. For convenience of explanation, the tissue G2 in FIG. 4 is assumed as the region of interest. In step S1, the operator operates the window selection button 4a of the operation device 4 to select the background window B, operates the window width change button 4b and the window level change button 4c, and the entire image is displayed on the display monitor 3. Adjust to see. In step S2, the operator selects the highlight window selection button 4 on the operation device 4.
The highlight window H is validated by operating d, and the highlight window width change button 4e and the highlight window level change button 4f are operated so that the organization G2 is displayed on the display monitor 3 with high brightness. When the steps S1 and S2 are completed, as shown in FIG. 4A, the CT value of the air G0 and the CT of the tissue G1 in the scan image.
The value and the CT value of the tissue G3 are converted into the brightness value of the low brightness part of the brightness gradation of the display monitor 3. On the other hand, the CT value of the tissue G2 of the scan image is converted into the brightness value of the high brightness portion of the brightness gradation of the display monitor 3. Therefore, as shown in FIG. 4B, the tissue G2, which is the region of interest, appears brighter and emphasized than other portions.

In step S3, the threshold acquisition unit 2e of the processing device 2 has the minimum CT value h of the highlight window H.
1 and the maximum value h2 are acquired and displayed on the display monitor 3. In step S4, the operator determines the minimum CT value h1 of the highlight window H displayed on the display monitor 3.
By observing the maximum value h2 and the maximum value h2, the lower limit and the upper limit of the CT value of the tissue G2 are recognized.

According to the above X-ray CT apparatus 100, although the display state is relatively low in brightness, the entire image can be viewed. Therefore, the operator can easily set the width H of the highlight window H so that the desired region of interest is displayed with high brightness.
W and the center position HL can be changed. And after the change,
A region of interest can be brightly emphasized in a relatively dark background. Further, from the minimum value and the maximum value of the CT value of the highlight window H, it becomes possible to know the lower limit value and the upper limit value of the CT value of the region of interest.

Although the X-ray CT apparatus has been described in the above embodiment, for example, MRI (Magnetic Resonan) is used.
ce imaging) equipment and other image diagnostic equipment
The present invention can be applied.

[0021]

According to the image display method, the image display device, and the image diagnostic device of the present invention, the entire image can be viewed although the display state is relatively low in luminance. Therefore,
The operator should set the desired region of interest to a high brightness display.
You can easily change the width or the center position of the highlight window. After the change, the region of interest is displayed brightly in the relatively dark background, so that the two can be clearly distinguished and viewed. Further, it becomes possible to easily and accurately know the lower limit value and the upper limit value of the pixel value of the region of interest.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an X-ray CT apparatus according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a background window and a highlight window in the X-ray CT apparatus of FIG.

FIG. 3 is a flow chart of an operation procedure performed by an operator using the X-ray CT apparatus in FIG.

FIG. 4 is an explanatory diagram of window processing using a background window and a highlight window.

FIG. 5 is a configuration diagram of an example of a conventional X-ray CT apparatus.

FIG. 6 is a conceptual diagram showing a window in the X-ray CT apparatus in FIG.

FIG. 7 is an explanatory diagram of window processing.

8 is a flow chart of an operation procedure performed by an operator using the X-ray CT apparatus in FIG.

FIG. 9 is an explanatory diagram showing a state where the center position of the window is moved to one end.

FIG. 10 is an explanatory diagram showing a state in which the center position of the window is adjusted to the minimum CT value of the region of interest.

FIG. 11 is an explanatory diagram showing a state in which the center position of the window is adjusted to the maximum CT value of the region of interest.

[Explanation of symbols]

 100 X-ray CT apparatus 1 Scanner apparatus 2 Processing apparatus 2a Normal window setting section 2b Background window setting section 2c Highlight window setting section 2d Window processing section 2e Threshold acquisition section 3 Display monitor 4 Operating device B Background window H Highlight window h1 CT Lower limit of value h2 Upper limit of CT value

Claims (4)

[Claims] 1. An image display method in which a pixel value is subjected to window processing to be converted into a luminance value, and an image is displayed on a display means based on the luminance value, wherein the range of the pixel value includes a background portion and a region of interest. And dividing the brightness gradation of the display means into at least two parts, a low brightness part and a high brightness part, and assigning a background window using the low brightness part to the background part. An image display method characterized in that a highlight window using the high-brightness portion is assigned to the area portion, and an operator can change the width or center position of the highlight window. 2. An image display device for windowing pixel values to convert them into brightness values, and displaying an image on a display means based on the brightness values, wherein the range of pixel values includes a background portion and a region of interest. When the brightness gradation of the display means is divided into at least two parts, that is, the low brightness part and the high brightness part, the pixel value of the background part is converted into the brightness value of the low brightness part. Background window processing means, highlight window processing means for converting pixel values of the region of interest into luminance values of the high brightness portion, and operating means for the operator to change the width or center position of the highlight window. An image display device comprising: 3. An image diagnostic apparatus for window-processing pixel values of a scan image obtained by scanning a subject to convert the pixel values into brightness values, and displaying an image on a display means based on the brightness values. When the value range is divided into at least two parts of a background part and a region of interest and the brightness gradation of the display means is divided into at least two parts of a low brightness part and a high brightness part, the pixel value of the background part To a brightness value of the low brightness part, a background window processing means, a highlight window processing means for converting a pixel value of the region of interest to a brightness value of the high brightness part, and a width or center of the highlight window. An image diagnostic apparatus comprising: an operation unit for an operator to change a position. 4. The image diagnostic apparatus according to claim 3, further comprising threshold acquisition means for acquiring the minimum value and the maximum value of the pixel values of the highlight window changed by the operator and displaying them on the display means. An image diagnostic apparatus characterized by: