JPH0683940A - Image display device - Google Patents

Abstract

PURPOSE:To provide the rage display device which can display a tissue image, whose border is hardly extracted, in three dimensions and also display not only the tissue image, but also its circumferential blood stream image in three dimensions at the same time. CONSTITUTION:The image display device is equipped with image data storage memories 1a and 1b which store 1st and 2nd three-dimensional image data corresponding to a specific three-dimensional space in a sample, a control part 2 which generates 1st projection image data regarding a specific view point by using the 1st three-dimensional image data distributed to the surface area of the remaining space obtained by removing a specific partial space from the three-dimensional space and also generates 2nd projection image data by using the 2nd three-dimensional image data distributed in the partial space, and then generate composite projection image data by superposing the 2nd projection image data on the 1st projection image data, a projection image storage memory 4 which stores the composite projection image data, and a display 5 which displays the composite projection image data as an image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device for displaying a medical image, and more particularly to an image display device for displaying a three-dimensional image.

[0002]

2. Description of the Related Art Conventionally, medical images of the inside of a subject include X-ray CT images, MRI images and ultrasonic tomographic images.

Although these medical images are tomographic images at a predetermined cross-sectional position of the subject, since the subject originally has a three-dimensional structure, an operator such as an inspecting doctor first looks within a predetermined diagnostic region. By making multiple tomographic images with, then observing these tomographic images, and finally reconstructing these tomographic images in the head, so-called mental construction, to grasp the three-dimensional structure of the diagnosis target site It is common to do.

However, when the site to be diagnosed has an anatomically complex three-dimensional structure, it may be difficult for an operator skilled in mental construction to grasp the three-dimensional structure. Not a few.

For this reason, recently, a three-dimensional display method has been researched and developed which makes it possible to easily grasp the three-dimensional structure of a site to be diagnosed.

[0006] First, when it is not necessary to extract the boundary of the diagnosis target region due to the nature of the imaging method, for example, a blood flow image is obtained by color flow mapping (hereinafter referred to as CFM) using an ultrasonic diagnostic apparatus. When the image is captured, the obtained three-dimensional image can be displayed three-dimensionally.

Japanese Patent Application No. 3-213 filed by the same applicant as the present application
Japanese Patent No. 625 discloses a technique of three-dimensionally displaying blood flow by rotating a blood flow image obtained using a CFM around a predetermined rotation axis and continuously displaying the blood flow image.

A similar three-dimensional blood flow image can be obtained by injecting a contrast medium into a blood vessel with an X-ray CT apparatus and photographing it, or by performing MR angiography with an MRI apparatus.

When it is easy to extract the boundary of the site to be diagnosed,
For example, when the site to be diagnosed is bone or the boundary is the epidermis, surface display such as the wire frame method that displays the boundary as a diagram or the surface method that fills the boundary and displays smoothly is effective. .

When it is difficult to extract the boundary of the diagnosis target region,
For example, when the diagnosis target site is an organ, the three-dimensional structure of the diagnosis target site can be grasped to some extent by displaying the above-mentioned tomographic image after cross-sectional conversion (MPR).

[0011]

However, in the cross-section conversion display, it is difficult to clearly grasp the three-dimensional structure of the site to be diagnosed as in the surface display.

Even if the surface of the organ can be displayed by extracting the boundary of the organ, the internal structure of the organ necessary for diagnosis cannot be known.

When it is clinically necessary to simultaneously observe the three-dimensional structure of a tissue and blood vessels around it, for example,
In order to investigate the influence of the tumor and the feeding blood vessels in the vicinity of the tumor, it is desired to display them three-dimensionally at the same time, but an image display method effective in such a case has not been developed yet.

The present invention has been made in consideration of the above-mentioned circumstances. In addition to displaying a three-dimensional tissue image in which boundaries are difficult to extract, not only the tissue image but also blood flow images in the vicinity thereof are simultaneously displayed.
An object is to provide an image display device capable of three-dimensional display.

[0015]

In order to achieve the above object, the image display apparatus of the present invention stores three-dimensional image data corresponding to a predetermined three-dimensional space in a subject as described in claim 1. An image data storage memory, a control unit that creates projection image data for a predetermined viewpoint using the three-dimensional image data distributed in the surface region of the residual space obtained by removing the predetermined subspace from the three-dimensional space; A projection image storage memory for storing image data and a display for displaying the projection image data as an image are provided.

Further, as described in claim 2, the image display device of the present invention stores first and second three-dimensional image data corresponding to a predetermined three-dimensional space in the subject.
First projection image data relating to a predetermined viewpoint using a second image data storage memory and the first three-dimensional image data distributed in the surface area of the residual space obtained by removing a predetermined subspace from the three-dimensional space Is created and second projection image data relating to the viewpoint is created using the second three-dimensional image data distributed in the subspace, and the second projection image data is added to the first projection image data. And a projection image storage memory for storing the combined projection image data, and a display for displaying the combined projection image data as an image.

[0017]

According to the image display device of the present invention, first, three-dimensional image data corresponding to a predetermined three-dimensional space in the subject is stored in the image data storage memory.

Here, in a preferred embodiment, the three-dimensional image data is tissue image data, more preferably B-mode ultrasonic tomographic image data, and non-binarized halftone display data ( (General 3D B-mode image is binarized data).

Next, the subspace to be removed from this three-dimensional space and the position of the viewpoint described later are set.

Next, using the three-dimensional image data distributed in the surface area of the residual space obtained by removing the subspace from the three-dimensional space, projection image data regarding the set viewpoint is created. This projection data has an intermediate gradation similar to that of a three-dimensional image.

Next, the projection image data is stored in the projection image storage memory and displayed on the display.

Regarding the creation and display of projection image data, in a preferred embodiment, two or more different subspaces are set and projection image data is created for each residual space corresponding to each subspace, and each projection image is created. The data is displayed on the display in a predetermined order and at predetermined time intervals.

In a further preferred embodiment, each subspace is set at a predetermined angle around a predetermined axis in the three-dimensional space, and the viewpoint is set at a predetermined position facing the subspace.

Further, according to the image display device of the present invention, first, the first and the second corresponding to a predetermined three-dimensional space in the subject.
The three-dimensional image data is stored in the first and second image data storage memories.

Here, in a preferred embodiment, the first three-dimensional image data is tissue image data, the second three-dimensional image data is blood flow image data, and more preferably the tissue image data is B-mode ultrasound. It is tomographic image data, and is halftone display data that has not been binarized. The blood flow image data is ultrasonic Doppler image data obtained by color flow mapping and is binarized or ternary data.

Next, the subspace to be removed from this three-dimensional space and the position of the viewpoint described later are set.

Next, using the first three-dimensional image data distributed in the surface region of the residual space obtained by removing the subspace from the three-dimensional space, the first projection image data regarding the set viewpoint is created and the subspace is generated. Second projection image data relating to the above-mentioned viewpoint is created using the second three-dimensional image data distributed in the image, and second projection image data is superimposed on the first projection image data to create composite projection image data. To do. It should be noted that the first projection data has an intermediate gradation similar to that of a three-dimensional image.

Next, the composite projection image data is stored in the projection image storage memory and displayed on the display.

Regarding the creation and display of the composite projection image data, in a preferred embodiment, two or more different subspaces are set and the composite projection image data is created for each of the residual spaces corresponding to the respective subspaces. The composite projection image data is displayed on the display in a predetermined order and at predetermined time intervals.

In a further preferred embodiment, each subspace is set at a predetermined angle around a predetermined axis in the three-dimensional space, and the viewpoint is set at a predetermined position facing the subspace.

[0031]

Embodiments of the image display device of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the image display device of this embodiment.

As shown in the figure, the image display device of this embodiment stores first and second three-dimensional image data corresponding to a predetermined three-dimensional space in the subject, respectively. Image data storage memories 1a and 1b.

In this embodiment, the first three-dimensional image data is tissue image data in medical image data, particularly B-mode ultrasonic tomographic image data (hereinafter referred to as B-mode image data).
The second three-dimensional image data will be described as blood flow image data in medical image data, particularly ultrasonic Doppler image data obtained by CFM (hereinafter, referred to as color Doppler image data).

The B-mode image data can be obtained as volume data distributed in the three-dimensional space by performing linear scanning, sector scanning, etc. in the above-mentioned three-dimensional space with the ultrasonic diagnostic apparatus.

Here, the image data at the position where scanning is not performed is preferably obtained by interpolation.

The B-mode image data is 8-bit information that can be expressed in shades of 256 gradations, for example.

The color Doppler image data is image data that can be obtained by performing CFM, and is the image data in which blood flow information is displayed in color by utilizing the Doppler effect of the ultrasonic beam.

The color Doppler image data is, for example, 1-bit information indicating the presence or absence of blood flow.

The image display apparatus according to the present embodiment includes a control unit 2 that creates predetermined combined projection image data using B-mode image data and color Doppler image data, and a projection image that stores the created combined projection image data. A storage memory 4 and a display 5 for displaying the combined projection image data as an image are provided.

As shown in FIG. 2, the control unit 2 removes the predetermined partial space 12 from the three-dimensional space 11 and the residual space 1
By using the first three-dimensional image data distributed in the surface region of No. 3, that is, the B-mode image data, the first projection image data regarding the predetermined viewpoint 14 and the projection surface 15 is created (FIG. 2).
Left half).

Here, the three-dimensional space 11 is a cube,
The subspace 12 is a space that is cut out from the three-dimensional space 11 by two planes that include the central axis 21 of the three-dimensional space 11 and are orthogonal to each other and a plane that divides the three-dimensional space 11 into upper and lower parts.

Since the three-dimensional space 11 rotates about the rotation axis 21 as will be described later, the partial space 12 at the rotational position in FIG. 2 happens to be a cube of a size that divides the three-dimensional space 11 into eight equal parts. However, if the three-dimensional space rotates, the shape of the subspace changes from a cube to another shape.

The control unit 2 uses the second three-dimensional image data distributed in the subspace 12, that is, the color Doppler image data, to create the second projection image data regarding the viewpoint 14 and the projection surface 15. (Right half of Figure 2).

When the second projection image data is created, a so-called Z-buffer algorithm (a method of changing the brightness depending on the depth distance) is used to display the gradation of a color such as red, thereby making it possible to display 3 It is good to express the dimensional depth by shading.

As a projection method for creating a projected image, there are a parallel projection method assuming that the viewpoint position is sufficiently far from the three-dimensional space, a perspective drawing method based on a predetermined viewpoint, and the like. However, in this embodiment, the projection image data is created using the perspective drawing method.

The viewpoint and the projection plane are preferably set by the input unit 3 shown in FIG.

The control unit 2 is configured to superimpose the second projection image data on the first projection image data to create composite projection image data.

FIG. 3 shows the created composite projection image data.

The control unit 2 is configured to set further subspaces and to create synthetic projection image data for each.

FIG. 4 (a) is the synthetic projection image data created for the subspace 12 and the residual space 13 described above, (b)
Is the combined projection image data created for the subspace 12a and the corresponding residual space 13a, and (c) is the subspace 1
2B shows the combined projection image data created for 2b and the corresponding residual space 13b.

As shown in FIG. 4, the control unit 2 sets each subspace 12, 12a, 12b at a predetermined angle around a predetermined axis 21 in the three-dimensional space 11 and sets each viewpoint as a subspace. It is configured to be set at a predetermined position facing 12, 12a, 12b.

FIG. 5 shows the directions 31, 32 and 33 seen from the respective viewpoints when the combined projection image data shown in FIGS. 4 (a), 4 (b) and 4 (c) are created.

Here, as for the relative positional relationship among the three-dimensional space, the subspace and the viewpoint, as shown in FIG. 4, while the three-dimensional space 11 rotates in the clockwise direction, the front portion always becomes the subspace. It may be considered that a blood flow image is displayed, and the three-dimensional space 11 is stationary, and while moving the viewpoint and the subspace in a counterclockwise direction around the three-dimensional space 11, the blood flow in the subspace is reduced. It may be considered that a flow image is displayed.

If the above-mentioned predetermined angle is, for example, 11.25 °, a total of 32 pieces of synthetic projection image data are created in one rotation.

It is preferable that the predetermined angle, that is, the creation angle pitch for creating the projection image, is set finely so that it can be sufficiently grasped as a three-dimensional structure during continuous display.

The projection image storage memory 4 is adapted to store the created composite projection image data for each angle.

Next, the operation of the image display device of this embodiment will be described.

FIG. 6 is a flow chart showing a procedure for three-dimensionally displaying a B mode image and a color Doppler image using the image display device of this embodiment.

First, the B mode image and the color Doppler image captured by the ultrasonic diagnostic apparatus are stored in the image data storage memories 1a and 1b, respectively.

Next, the viewpoint, the creation angle pitch, and the rotation axis line in the three-dimensional space when creating the projected image are set by the input unit 3.

Next, the three-dimensional space is positioned so that the set rotation axis is, for example, in the vertical direction on the display.

Next, the subspace is removed from the three-dimensional space.

Next, the projection image data for the above-mentioned viewpoint is created from the B-mode image data distributed in the surface area of the residual space where the subspace is removed. This projection image data has the same gradation as the three-dimensional image.

At the same time, projection image data for the above-mentioned viewpoint is created from the color Doppler image data distributed in the subspace. This projected image has gradation according to the distance from the viewpoint.

Next, the two created projection image data are superposed to create composite projection image data.

Next, the composite projection image data is stored in the projection image storage memory.

Then, the three-dimensional space is rotated by the creation angle pitch, for example, 11.25 °, and the above procedure is repeated.

Here, when the rotation angle of the three-dimensional space exceeds 360 °, the creation of the synthetic projection image data is completed.

Finally, the 32 composite projection image data thus created are continuously displayed on the display 5 at predetermined time intervals.

As described above, the image display apparatus of this embodiment is configured so that the B-mode image and the color Doppler image can be displayed at the same time. Therefore, for example, a tumor and the surrounding feeding blood vessels can be observed simultaneously. it can.

Therefore, it is possible to accurately and efficiently determine the tumor removal range, the effect of treatment such as ethanol embolization, and the benign or malignant tumor.

In addition, a subspace is set, and B distributed in the surface area of the residual space obtained by removing the subspace from the three-dimensional space.
Since the mode image data is displayed as a projection image, the tumor can be displayed three-dimensionally without extracting the boundary of the tumor.

Therefore, the diagnosis time can be shortened and the diagnosis accuracy can be improved, and by storing these data, it can be effectively used as an explanatory material for patients and the like.

Since a plurality of subspaces are set and the synthetic projection image data for each subspace is continuously displayed, for example, the three-dimensional structure of the tumor itself can be clearly understood and the nutrition around the tumor can be clearly understood. The relationship with blood vessels can be observed three-dimensionally.

Further, in the image display device of the present embodiment, when setting a plurality of subspaces, a predetermined rotation axis is set in the three-dimensional space, and the three-dimensional space is rotated around this rotation axis while the subspace is rotated. Was set up, and synthetic projection image data was created for each such subspace and continuously rotated and displayed. Therefore, for example, to more clearly understand the three-dimensional structure of the tumor or the tumor and the vegetative blood vessels around the tumor. You can

In this embodiment, a plurality of synthetic projection image data are displayed for different subspaces, but only one synthetic projection image data may be displayed for a predetermined subspace.

Even with such a structure, it is possible to observe the three-dimensional structure of the tumor and simultaneously observe the tumor and the surrounding feeding blood vessels three-dimensionally.

In this embodiment, a predetermined rotation axis is set in the three-dimensional space, and the partial space is set while rotating the three-dimensional space around the rotation axis by a predetermined angle. The present invention is not limited to this, and for example, a plurality of synthetic projection image data may be continuously displayed so that a fractured surface, which is a boundary surface between the partial space and the residual space, moves substantially in parallel.

Further, in the present embodiment, the three-dimensional space is described as a cube, but the shape is not limited to this and can be set to any shape.

For example, a cylindrical three-dimensional space 41 may be used as shown in FIG. 7 (a).

The partial space at this time is not a cubic shape like the partial space 12, but a partial space 42 having the shape shown in FIG.

Further, in the present embodiment, the subspace is defined as a space cut by two planes that include the central axis of the three-dimensional space and are orthogonal to each other and a plane that divides the three-dimensional space into upper and lower parts. Not limited to the shape, it can be set to any shape.

For example, as shown in FIG. 7 (b), a partial space 43 having a shape obtained by dividing a sphere into eight at a predetermined rotation position may be used, or as shown in FIG. 7 (c), a three-dimensional space may be formed. A triangular prism-shaped partial space 44 obtained by dividing 11 by half may be used.

In this embodiment, the B-mode image is taken as an example of the tissue image data, but the present invention is not limited to this and may be, for example, an MRI image or a CT image.

Although the color Doppler image is taken as the blood flow image data, it may be an image obtained by MR angiography, for example.

Furthermore, the image display device of the present invention is not necessarily required for the tissue image and the blood flow image of the human body, and the three-dimensional image data for which the boundary extraction is difficult and the three-dimensional image data for which the surface can be displayed are used. It can be applied, and for example, an internal structure image and a defect image of the structural material can be displayed simultaneously.

Further, in the present embodiment, the three-dimensional depth is expressed by shading with the Z-buffer algorithm, but when three-dimensional display can be sufficiently achieved by rotating and continuously displaying a large number of projection image data. May be unshaded with the Z-buffer algorithm.

The shading may be performed by a method other than the Z-buffer algorithm, for example, a phong shading model, a method in which the reflection direction of light is taken into consideration, or the maximum value used in MR angiography. A projection method may be used.

In the above embodiment, the case where the B-mode image and the color Doppler image are displayed simultaneously has been described.
It goes without saying that the mode image can be displayed independently.

Even in such a case, as described above, the tumor can be three-dimensionally displayed without extracting the boundary of the tumor, and the surface and the inside of the tumor can be observed simultaneously.

The modified example of the case of displaying only the B-mode image is substantially the same as the modified example described above with respect to the embodiment in which the B-mode image and the color Doppler image are simultaneously displayed except for the modified example regarding the Z-buffer algorithm. Since this is the case, the description is omitted here.

[0093]

As described above, the image display apparatus according to the present invention has an image data storage memory for storing three-dimensional image data corresponding to a predetermined three-dimensional space in the subject and a predetermined one from the three-dimensional space. Control unit for creating projection image data for a predetermined viewpoint using the three-dimensional image data distributed in the surface area of the residual space obtained by removing the subspace, a projection image storage memory for storing the projection image data, and the projection Since a display for displaying image data as an image is provided, it is possible to three-dimensionally display a tissue image for which boundary extraction is difficult.

Further, the image display device of the present invention includes first and second image data storage memories for respectively storing first and second three-dimensional image data corresponding to a predetermined three-dimensional space in the subject. , Creating first projection image data relating to a predetermined viewpoint using the first three-dimensional image data distributed in the surface area of the residual space obtained by removing a predetermined subspace from the three-dimensional space, and The second distributed in
A control unit that creates second projection image data relating to the viewpoint by using the three-dimensional image data, and creates composite projection image data by superimposing the second projection image data on the first projection image data. Since the projection image storage memory for storing the composite projection image data and the display for displaying the composite projection image data as an image are provided, not only the tissue image is displayed three-dimensionally but also the tissue image in which the boundary extraction is difficult is displayed. Blood flow images in the vicinity can be simultaneously displayed three-dimensionally.

[Brief description of drawings]

FIG. 1 is a block diagram of an image display device according to an embodiment.

FIG. 2 is a diagram showing a procedure for creating projection image data using the image display device of this embodiment.

FIG. 3 is a diagram showing combined projection image data in which two pieces of projection image data are superimposed.

FIG. 4 is a diagram showing synthetic projection image data created one after another by rotating a three-dimensional space.

5 is a diagram showing a viewpoint from which the synthetic projection image data shown in FIG. 4 is created.

FIG. 6 is a flowchart showing a procedure for simultaneously displaying a B-mode image and a color Doppler image using the image display device of this embodiment.

FIG. 7 is a diagram showing a modified example of a three-dimensional space and a partial space in the image display device of the present embodiment.

[Explanation of symbols]

 1 image data storage memory 2 control unit 3 input unit 4 projected image storage memory 5 display

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location G09G 5/36 9177-5G

Claims (6)

[Claims] 1. An image data storage memory for storing three-dimensional image data corresponding to a predetermined three-dimensional space in a subject, and a surface area of a residual space obtained by removing a predetermined subspace from the three-dimensional space. A control unit that creates projection image data regarding a predetermined viewpoint using three-dimensional image data,
An image display device, comprising: a projection image storage memory for storing the projection image data; and a display for displaying the projection image data as an image. 2. A first and a second image data storage memories for respectively storing first and second three-dimensional image data corresponding to a predetermined three-dimensional space in a subject, and a predetermined memory from the three-dimensional space. The first three-dimensional image data distributed in the surface area of the residual space from which the subspace is removed is used to create first projection image data for a predetermined viewpoint, and the second cubic is distributed in the subspace. Second projection image data relating to the viewpoint is created using the original image data, and the first projection image data is created.
A control unit for superimposing the second projection image data on the projection image data to create composite projection image data, a projection image storage memory for storing the composite projection image data, and the composite projection image data as an image. An image display device comprising a display. 3. The control unit sets two or more different subspaces, creates the composite projection image data for each, and displays the composite projection image data in a predetermined order and at a predetermined time interval. The image display device according to claim 2, configured to: 4. The control unit sets each of the subspaces at a predetermined angle around a predetermined axis in the three-dimensional space, and sets the viewpoint at a predetermined position facing the subspace. The image display device according to claim 3, wherein the image display device comprises 5. The image display according to claim 2, wherein the first three-dimensional image data is tissue image data in medical image data, and the second three-dimensional image data is blood flow image data in medical image data. apparatus. 6. The image display device according to claim 5, wherein the tissue image data is B-mode ultrasonic tomographic image data, and the blood flow image data is ultrasonic Doppler image data obtained by color flow mapping.