JPH1031761A - Image display method and image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simultaneously display a surface stage and an internal state by producing two-dimensional images for which tomographic images or the like are worked at a cross section position set near a view point. SOLUTION: An endoscopic mode three-dimensional image producing and display part 2d extracts the pixels of a CT value range inside a visual field radially spread from the view point in a visual field center line direction from the data of the two-dimensional images of respective slices, produces the three- dimensional images of viewing the wall surface of an invivo structure and displays them at a display device 3. The cross section position is determined within a prescribed range near a view point position and the cross section position is inputted from an input device 4. A cross section position input part 2e receives the inputted cross section position and delivers it to a peripheral image producing and display part 2f. The part 2f produces the tomographic images on a cross section vertical to a visual field center line at the cross section position, based on the data of the two-dimensional images, produces peripheral images for which the area of the three-dimensional images is eliminated from the tomographic images and displays them at the display device 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image display method and an image display device, and more particularly, to an image display method and an image display device capable of simultaneously displaying a surface state and an internal state.

[0002]

FIG. 13 shows a conventional X-ray CT (Computed).
1 is a configuration diagram illustrating an example of a tomography apparatus. The X-ray CT apparatus 500 includes a scanner apparatus 1 and an image processing apparatus 5
2, a display device 3, and an input device 4. The image processing device 52 includes a two-dimensional image creation display unit 2a, a CT value range input unit 2b, a viewpoint position / view center line direction input unit 2c, and an endoscope mode three-dimensional image creation display unit 52d. In.

The scanner device 1 scans a patient K at different slice (plate-shaped tomographic imaging region) positions and collects scan data of a plurality of slices. Image processing device 5
The two two-dimensional image creation and display unit 2a processes the scan data of the plurality of slices, creates two-dimensional image data of each slice, and displays the two-dimensional image on the display device 3. An operator reads a CT value range of a body structure (for example, a digestive tract or a blood vessel) from which a three-dimensional image in the endoscope mode is desired to be created from a two-dimensional image, and inputs the CT value range from the input device 4. Image processing device 5
The 2nd CT value range input unit 2b receives the input CT value range and outputs the endoscope mode 3D image creation display unit 52
pass to d.

An operator determines a viewpoint position (a lens position of a virtual endoscope) in the internal space of the internal structure, and inputs the viewpoint position from the input device 4. The direction of the center line of the visual field (the direction of the lens optical axis of the virtual endoscope) is input from the input device 4. The viewpoint position / view center line direction input unit 2c of the image processing device 52 receives the input viewpoint position and view center line direction, and passes them to the endoscope mode three-dimensional image creation display unit 52d.

[0005] An endoscope mode three-dimensional image creation display section 52d of the image processing device 52 displays a pixel (pixel) in the CT value range of each slice in a field of view extending radially from the viewpoint to the center line of the field of view. A three-dimensional image is created from the data of the two-dimensional image by looking at the wall of the internal structure, and the three-dimensional image is displayed on the display device 3.

FIG. 14 is a flowchart showing a procedure for displaying a three-dimensional image in the endoscope mode using the X-ray CT apparatus 500. In step V1, the patient K is scanned at different slice positions, and data of a plurality of continuous two-dimensional images is obtained. FIG. 15 illustrates a plurality of continuous two-dimensional images S1 to S7. In the figure, D is the large intestine.
K is a lumen which is an internal space of the large intestine D.

Returning to FIG. 14, in step V2, the operator uses the input device 4 to select an appropriate one of the plurality of continuous two-dimensional images. For example, S5 in the two-dimensional images S1 to S7 is selected. In step V3, the operator reads and inputs the CT value range of the internal structure (for example, large intestine D) for which a three-dimensional image in the endoscope mode is desired to be created from the selected two-dimensional image. For example, if the CT value range of the pixel of the large intestine D is “300 or more” in the two-dimensional image S5, CT
"300" is input as the lower limit of the value range (if necessary, the upper limit may be further input). In step V4, the operator determines a viewpoint position in the internal space of the internal structure, and inputs the viewpoint position. For example, as shown in FIG. 16, the cursor U is pointed to a point in the lumen K which is the internal space of the large intestine D, and pointing is performed. Also, the direction of the line of sight center line is input. For example, the user inputs the “backward direction” of the displayed two-dimensional image.

Returning to FIG. 14, in step V5, the endoscope mode three-dimensional image creation display unit 5 of the image processing device 52
2d is such that a pixel (pixel) in the CT value range is extracted from data of a two-dimensional image of each slice in a visual field radially extending in the direction of the visual field center line from the visual point, and a wall of an internal structure is viewed. Create a three-dimensional image. For example, a three-dimensional image T as shown in FIG. 17 is created. In the figure, A is a tumor formed on the intestinal wall of the large intestine D. Returning to FIG. 14, in step V6a, the endoscope mode three-dimensional image creation display unit 52d of the image processing device 52
Displays a three-dimensional image on the display device 3. In step V7a, it is checked whether the operator has changed the viewpoint position or the direction of the center of the visual field. If the operator has not changed, the current display is maintained. If the operator has changed, the process returns to step V5 to update the three-dimensional image.

[0009]

The above-mentioned conventional X-ray CT apparatus 500 displays a three-dimensional image as viewed by a virtual endoscope. This three-dimensional image conveys the surface condition of the internal structure to the operator, but does not convey internal information. That is, only the surface state can be displayed.
However, there is a problem in that it is not possible to display the internal state for grasping how deep the inside extends. Therefore, an object of the present invention is to provide an image display method and an image display device capable of simultaneously displaying a surface state and an internal state.

[0010]

According to a first aspect, the present invention creates a three-dimensional image of a wall surface of a three-dimensional structure as viewed from a viewpoint outside the three-dimensional structure, and converts the three-dimensional image. In the image display method for displaying, a tomographic image at a cross-sectional position set near the viewpoint or a cross-sectional image of the three-dimensional structure or a two-dimensional image obtained by processing them is created and arranged along with the three-dimensional image or Provided is an image display method characterized by combining and displaying a three-dimensional image. In the image display method according to the first aspect,
At the same time as displaying a three-dimensional image (for example, a three-dimensional image in an endoscope mode) as if a three-dimensional structure was viewed from a certain viewpoint, a tomographic image near the viewpoint or a cross-sectional image of the three-dimensional structure, or the like. Is displayed. Therefore, the surface state and the internal state can be displayed simultaneously.

In a second aspect, the present invention provides a three-dimensional image creating means for creating a three-dimensional image of a wall surface of a three-dimensional structure as viewed from a viewpoint outside the three-dimensional structure; A two-dimensional image creating means for creating a tomographic image at the set sectional position or a sectional image of the three-dimensional structure or a two-dimensional image obtained by processing the sectional image, and the tomographic image or the sectional image or the two-dimensional image An image display device comprising: image display means for displaying the image alongside or combining with the three-dimensional image. The image display device according to the second aspect can suitably implement the image display method according to the first aspect. Therefore, for example, it is possible to simultaneously display the surface state and the internal state of the seed tumor A formed on the intestinal wall of the large intestine.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the embodiments shown in the drawings. Note that the present invention is not limited by this.

First Embodiment FIG. 1 is a configuration diagram of an X-ray CT apparatus according to a first embodiment of the present invention. The X-ray CT apparatus 100 includes a scanner device 1, an image processing device 2, a display device 3, and an input device 4. The image processing device 2
Are a two-dimensional image creation / display unit 2a, a CT value range input unit 2b, a viewpoint position / view center line direction input unit 2c, an endoscope mode three-dimensional image creation / display unit 2d, and a cross-section position input unit 2e. , A peripheral image creation display unit 2f.

The scanner device 1 scans the patient K at different slice (plate-shaped tomographic imaging area) positions and collects scan data of a plurality of slices. Image processing device 2
The two-dimensional image creation display unit 2a processes the scan data of the plurality of slices to create two-dimensional image data of each slice, and displays the two-dimensional image on the display device 3.
To be displayed. The operator wants to create a three-dimensional image in the endoscope mode (eg, a gastrointestinal tract or a blood vessel).
Is read from the two-dimensional image, and the CT value range is input from the input device 4. Image processing device 2
The CT value range input unit 2b receives the input CT value range and passes it to the endoscope mode three-dimensional image creation display unit 2d.

An operator determines a viewpoint position (a lens position of a virtual endoscope) in the internal space of the internal structure, and inputs the viewpoint position from the input device 4. The direction of the center line of the visual field (the direction of the lens optical axis of the virtual endoscope) is input from the input device 4. The viewpoint position / view center line direction input unit 2c of the image processing device 2 receives the input viewpoint position and view center line direction, and outputs the endoscope mode three-dimensional image creation display unit 2
pass to d.

The endoscope mode three-dimensional image creation / display unit 2d of the image processing apparatus 2 assigns a pixel (pixel) in the CT value range to each slice in a field of view extending radially from the viewpoint to the center line of the field of view. A three-dimensional image is created from the data of the two-dimensional image by looking at the wall of the internal structure, and the three-dimensional image is displayed on the display device 3.

An operator determines a cross-sectional position within a predetermined range near the viewpoint position, and inputs the cross-sectional position from the input device 4. The cross-section position input unit 2e of the image processing device 2 receives the input cross-section position and outputs the received cross-sectional position.
pass to f.

The peripheral image creation / display section 2f of the image processing device 2 creates a tomographic image in a cross section perpendicular to the visual field center line at the cross sectional position based on the data of the two-dimensional image. A peripheral image (see FIG. 5) in which the area of the dimensional image is deleted is created and displayed on the display device 3.

FIG. 2 is a flowchart of a procedure for displaying a three-dimensional image in the endoscope mode using the X-ray CT apparatus 100. In step V1, the patient K is scanned at different slice positions, and data of a plurality of continuous two-dimensional images is obtained. FIG. 15 illustrates a plurality of continuous two-dimensional images S1 to S7. In the figure, D is the large intestine. K
Is a lumen which is an internal space of the large intestine D.

Returning to FIG. 2, in step V2, the operator uses the input device 4 to select an appropriate one of the plurality of continuous two-dimensional images. For example, S5 in the two-dimensional images S1 to S7 is selected. In step V3, the operator reads and inputs the CT value range of the internal structure (for example, large intestine D) for which a three-dimensional image in the endoscope mode is desired to be created from the selected two-dimensional image. For example, if the CT value range of the pixel of the large intestine D is “300 or more” in the two-dimensional image S5, CT
"300" is input as the lower limit of the value range (if necessary, the upper limit may be further input). In step V4, the operator determines a viewpoint position in the internal space of the internal structure, and inputs the viewpoint position. For example, as shown in FIG. 16, the cursor U is pointed to a point in the lumen K which is the internal space of the large intestine D, and pointing is performed. Also, the direction of the line of sight center line is input. For example, the user inputs the “backward direction” of the displayed two-dimensional image.

Returning to FIG. 2, in step V5, the endoscope mode three-dimensional image creation display unit 2d of the image processing apparatus 2
Is such that a pixel (pixel) in the CT value range is extracted from data of a two-dimensional image of each slice in a field of view extending radially from the viewpoint to the direction of the center line of the field of view, and the wall of the internal structure is viewed. Create a dimensional image. For example, a three-dimensional image T as shown in FIG. 17 is created.
In the figure, A is a tumor formed on the intestinal wall of the large intestine D. Returning to FIG. 2, in step V6, the endoscope mode three-dimensional image creation display unit 2d of the image processing device 2 displays the three-dimensional image T in the left area GL of the screen of the display device 3, as shown in FIG. I do. In step V7, it is checked whether the operator has changed the viewpoint position or the visual field center direction, and if it has been changed, the process returns to step V5 to update the three-dimensional image, and if not changed, the process proceeds to step V8. That is, while the viewpoint position or the direction of the center line of the visual field is being changed, the three-dimensional image is continuously changed in accordance with the change, and when stopping at a certain three-dimensional image, the process proceeds to step V8.

In step V8, the peripheral image creation display unit 2f of the image processing device 2 sets the position included in the three-dimensional image and closest to the front as the cross-sectional position. Step V9
Then, a tomographic image is created by extracting pixels of a cross section perpendicular to the visual field center line at the cross section position from the data of the two-dimensional image. For example, in the case shown in FIG. 4, a position closest to the viewpoint E1 in the intestinal wall portion of the large intestine D included in the field of view is a cross section Q1, and a tomographic image of this cross section is created. Next, the area of the three-dimensional image is deleted from the tomographic image, and FIG.
A peripheral image C as shown in FIG. Returning to FIG.
In step V10, the peripheral image creation display unit 2f of the image processing device 2 displays the peripheral image C in the right region GR of the screen of the display device 3, as shown in FIG. Returning to FIG. 2, in step V11, a sectional position display SL is performed on the three-dimensional image T as shown in FIG.

At step V12, it is checked whether or not the operator has changed the cross-sectional position.
Then, the peripheral image is updated, the peripheral image is displayed in step V10, and the sectional position is displayed in step V11. For example, if the sectional position is moved to the back, the display is as shown in FIG.

In step V13, it is checked whether the operator has changed the viewpoint position or the direction of the center of the visual field. If not, the process returns to step V12 to maintain the current display.
After the change, the process proceeds to step V14. In step V14, the peripheral image C is deleted, and the display returns to the display in FIG. Then, the process returns to step V5. That is, when the viewpoint position or the visual field center line direction is changed, the three-dimensional image T is changed according to the change, and the peripheral image C is not displayed while the three-dimensional image T is changed.

X-ray CT apparatus 1 according to the first embodiment
According to 00, the three-dimensional image T in the endoscope mode is displayed in the left area of the screen of the display device 3, and the peripheral image C is displayed in the right area of the screen when the viewpoint stops, so that the surface of the tumor A The state and the internal state (such as the CT value inside the tissue) can be displayed simultaneously.

In step V10, the tomographic image may be displayed as it is. Further, a cross-sectional image of the internal structure at a cross-section perpendicular to the visual field center line at the cross-sectional position may be created based on the three-dimensional data at the cross-sectional position, and the cross-sectional image may be displayed at the step V10. .

Second Embodiment FIG. 9 is a configuration diagram of an X-ray CT apparatus according to a second embodiment of the present invention. The X-ray CT apparatus 200 includes a scanner device 1, an image processing device 12, a display device 3, and an input device 4. The image processing device 1
2, a two-dimensional image creation / display unit 2a, a CT value range input unit 2b, a viewpoint position / view center line direction input unit 2c,
It includes an endoscope mode three-dimensional image creation display unit 12d, a section position input unit 2e, a section image creation unit 2f, and an image synthesis display unit 12g.

The scanner device 1 scans the patient K at different slice positions and collects scan data of a plurality of slices. The two-dimensional image creation display unit 2a of the image processing device 12 processes the scan data of the plurality of slices, creates two-dimensional image data of each slice, and displays the two-dimensional image on the display device 3. The operator reads a CT value range of a body structure (for example, a digestive tract or a blood vessel) for which a three-dimensional image in the endoscope mode is to be created from the two-dimensional image, and inputs the CT value range from the input device 4. . The CT value range input unit 2b of the image processing device 12 receives the input CT value range and passes it to the endoscope mode three-dimensional image creation display unit 12d.

The operator determines a viewpoint position in the internal space of the internal structure, and inputs the viewpoint position from the input device 4. The direction of the center line of the visual field is input from the input device 4.
View point position / view center line direction input unit 2 of image processing device 12
c receives the input viewpoint position and visual field center line direction, and passes them to the endoscope mode three-dimensional image creation display unit 12d.

The endoscope mode three-dimensional image creation display unit 12d of the image processing device 12 extracts the pixels (pixels) in the CT value range from the data of the two-dimensional image of each slice, and extracts the three-dimensional data of the internal structure. And, based on the three-dimensional data, a three-dimensional image (see FIG. 17) as if the wall of the internal structure was viewed from the viewpoint in a field of view extending radially in the direction of the center line of the field of view from the viewpoint. 3
To be displayed.

The operator determines a cross-sectional position within a predetermined range near the viewpoint position, and inputs the cross-sectional position from the input device 4. The cross-section position input unit 2e of the image processing device 12 receives the input cross-section position and passes it to the peripheral image creation display unit 2f.

Section image creation section 12f of image processing device 12
Is a cross-sectional image of a body structure at a cross-section perpendicular to the visual field center line at the cross-sectional position based on the three-dimensional data (FIG. 11).
See). The image synthesis display unit 12g of the image processing device 12 synthesizes the three-dimensional image and the cross-sectional image, and displays the synthesized image (see FIG. 12) on the screen of the display device 3.

FIG. 10 is a flowchart of a procedure for displaying a three-dimensional image in the endoscope mode using the X-ray CT apparatus 200. In step V1, the patient K is scanned at different slice positions, and data of a plurality of continuous two-dimensional images is obtained. FIG. 15 illustrates a plurality of continuous two-dimensional images S1 to S7. In the figure, D is the large intestine.
K is a lumen which is an internal space of the large intestine D.

Returning to FIG. 10, in step V2, the operator uses the input device 4 to select an appropriate one of the plurality of continuous two-dimensional images. For example, S5 in the two-dimensional images S1 to S7 is selected. In step V3, the operator reads and inputs the CT value range of the internal structure (for example, large intestine D) for which a three-dimensional image in the endoscope mode is desired to be created from the selected two-dimensional image. For example, if the CT value range of the pixel of the large intestine D is “300 or more” in the two-dimensional image S5, CT
"300" is input as the lower limit of the value range (if necessary, the upper limit may be further input). In step V4, the operator determines a viewpoint position in the internal space of the internal structure, and inputs the viewpoint position. For example, as shown in FIG. 16, the cursor U is pointed to a point in the lumen K which is the internal space of the large intestine D, and pointing is performed. Also, the direction of the line of sight center line is input. For example, the user inputs the “backward direction” of the displayed two-dimensional image.

Returning to FIG. 10, in step V5a, the endoscope mode three-dimensional image creation / display section 12d of the image processing device 12 sets the pixels in the CT value range to 2 in each slice.
The three-dimensional data of the internal structure is created by extracting from the data of the three-dimensional image, and the wall surface of the internal structure is viewed from the viewpoint in the field of view extending radially in the direction of the center line of the visual field based on the three-dimensional data. Create a three-dimensional image as shown below. For example, a three-dimensional image T as shown in FIG. 17 is created. In the figure, A is a tumor formed on the intestinal wall of the large intestine D. Returning to FIG. 10, in step V6a, the endoscope mode three-dimensional image creation display unit 12d of the image processing device 12
Displays the three-dimensional image T on the display device 3. In step V7, it is checked whether the operator has changed the viewpoint position or the direction of the visual field center, and if so, the process returns to step V5a to update the three-dimensional image (there is no need to re-create the three-dimensional data), and to make the change. If not, the process proceeds to step V8a. That is, while the viewpoint position or the direction of the center line of the visual field is being changed, the three-dimensional image is continuously changed in accordance with the change.

In step V8a, the section image creating section 12f of the image processing device 12 sets the innermost position included in the three-dimensional image as the section position. In step V9a, a cross-sectional image is created by extracting pixels of a cross section perpendicular to the visual field center line at the cross-sectional position from the three-dimensional data. For example, a cross-sectional image E as shown in FIG. 11 is created. Returning to FIG. 10, in step V10a, the image synthesis display unit 12g of the image processing device 12 deletes an area in front of the cross-sectional position of the three-dimensional image and synthesizes the image with the cross-sectional image to create a synthesized image. As shown in FIG. 12, the composite image I is displayed.

Returning to FIG. 10, in step V12, it is checked whether or not the operator has changed the cross-sectional position, and if so, the flow returns to step V9a to update the cross-sectional image.
In step 10a, a composite image is created and displayed. Step V1
In step 3, it is checked whether the operator has changed the viewpoint position or the visual field center direction. If the operator has not changed, the process returns to step V12 to maintain the current display.
Proceed to 4. In step V14, the composite image I is deleted, and the display returns to the display in FIG. Then, the process returns to step V5a. That is, when the viewpoint position or the direction of the center line of the visual field is changed, the three-dimensional image T is changed in accordance with the change.
While the dimensional image T is being changed, the composite image I is not displayed.

X-ray CT apparatus 2 according to the second embodiment
According to 00, the three-dimensional image T in the endoscope mode is displayed on the screen of the display device 3, and when the viewpoint is stopped, the synthesized image I obtained by synthesizing the three-dimensional image T and the cross-sectional image E is displayed on the screen. Thus, the surface state and internal state (such as CT value) of the tumor A can be displayed simultaneously.

In step V9a, a tomographic image in a cross section perpendicular to the center line of the visual field at the cross-sectional position is created based on the data of the two-dimensional image, and the tomographic image and the three-dimensional image are combined in step V10a. May be displayed.

In the above embodiment, a case has been described in which data of a plurality of two-dimensional images is used to create a three-dimensional image. However, three-dimensional volume data may be used. Further, in the above embodiment, the X-ray CT apparatus has been described, but for example, an MRI (Magnetic Resonanan) is used.
ce Imaging) devices, such as
The present invention can be applied.

[0041]

According to the image display method and the image display apparatus of the present invention, a three-dimensional structure as viewed from a certain viewpoint is obtained.
In addition to the two-dimensional image (for example, a three-dimensional image in a so-called endoscope mode), a two-dimensional image of a region corresponding to the periphery of the three-dimensional image is displayed, so that the surface state and the internal state can be simultaneously displayed. .

[Brief description of the drawings]

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

FIG. 2 shows an endoscope mode 3 using the X-ray CT apparatus of FIG.
It is a flowchart of the procedure of displaying a dimensional image.

FIG. 3 is an explanatory diagram of displaying a three-dimensional image by the X-ray CT apparatus of FIG. 1;

FIG. 4 is an explanatory diagram showing a positional relationship between a viewpoint and a cross section.

FIG. 5 is a conceptual diagram showing a peripheral image obtained by the X-ray CT apparatus of FIG.

FIG. 6 is an explanatory diagram of a display of a three-dimensional image and a peripheral image by the X-ray CT apparatus of FIG. 1;

FIG. 7 is an explanatory diagram of display of a three-dimensional image, a peripheral image, and a cross-sectional position by the X-ray CT apparatus of FIG. 1;

FIG. 8 is an explanatory diagram of another display of a three-dimensional image, a peripheral image, and a cross-sectional position by the X-ray CT apparatus of FIG. 1;

FIG. 9 is a configuration diagram illustrating an X-ray CT apparatus according to a second embodiment of the present invention.

FIG. 10 is a flowchart of a procedure for displaying a three-dimensional image in an endoscope mode using the X-ray CT apparatus of FIG. 9;

FIG. 11 is a conceptual diagram showing a cross-sectional image obtained by the X-ray CT apparatus of FIG.

FIG. 12 is a conceptual diagram showing a composite image obtained by the X-ray CT apparatus of FIG.

FIG. 13 is a configuration diagram illustrating an example of a conventional X-ray CT apparatus.

FIG. 14 is a flowchart of a procedure for displaying a three-dimensional image in an endoscope mode using the X-ray CT apparatus of FIG. 13;

FIG. 15 is a schematic diagram showing a plurality of two-dimensional images serving as a basis of a three-dimensional image.

FIG. 16 is an explanatory diagram of a screen for inputting a viewpoint on a two-dimensional image.

FIG. 17 is a schematic view showing a three-dimensional image obtained by the X-ray CT apparatus of FIG.

[Explanation of symbols]

100, 200, 500 X-ray CT apparatus 1 Scanner apparatus 2, 12, 52 Processing unit 2a 2D image creation display unit 2b CT value range input unit 2c Viewpoint position / line-of-sight centerline direction input unit 2d, 12d, 52d Endoscope Mode 3D image creation display unit 2e Cross section position input unit 2f Peripheral image creation display unit 12f Cross section image creation unit 12g Image synthesis display unit 3 Display device 4 Input device C Peripheral image E Cross section image I Synthetic image K Lumen S1 to S7 2 3D image T 3D image

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Manabu Minami 5-6-15 Kita-Terao # 301, Tsurumi-ku, Yokohama-shi, Kanagawa

Claims (2)

[Claims] 1. A three-dimensional image of a wall surface of a three-dimensional structure as viewed from a viewpoint outside the three-dimensional structure.
In an image display method for displaying a three-dimensional image, a tomographic image at a cross-sectional position set near the viewpoint or a cross-sectional image of the three-dimensional structure or a two-dimensional image obtained by processing them
An image display method comprising: creating a three-dimensional image, and arranging the three-dimensional image or combining the three-dimensional image with the three-dimensional image and displaying the combined image. 2. A three-dimensional image creating means for creating a three-dimensional image of a wall surface of a three-dimensional structure as viewed from a viewpoint outside the three-dimensional structure, and a tomogram at a sectional position set near the viewpoint. A two-dimensional image creating means for creating an image or a cross-sectional image of the three-dimensional structure or a two-dimensional image obtained by processing the three-dimensional structure; and arranging the tomographic image, the cross-sectional image, or the two-dimensional image with the three-dimensional image, or An image display device, comprising: an image display means for combining and displaying a two-dimensional image.