JP4110226B2 - 3D image display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a three-dimensional image display device with a guide image, and in particular, a three-dimensional image display device capable of displaying the inside of an observation target as an image viewed with an endoscope (hereinafter referred to as an endoscopic image). About.
[0002]
[Prior art]
The medical image includes various images such as an X-ray CT image, an MRI image, and an ultrasonic tomographic image. As a method of obtaining a pseudo three-dimensional image, a viewpoint and a projection plane are given, and a three-dimensional original image (a plurality of tomographic images) existing between the viewpoint and the projection plane is viewed from the viewpoint on the projection plane. There is a projection method to project. As the projection method, a parallel projection method and a central projection method are known.
[0003]
In order to obtain an endoscopic image, a central projection method in which the viewpoint can be set inside the observation target is used. This central projection method for obtaining an endoscopic image is described in Japanese Patent Application Laid-Open Nos. 7-210704 and 7-296184.
[0004]
[Problems to be solved by the invention]
However, since the viewpoint of the endoscopic image obtained by the central projection method is set inside the observation target, it is possible to determine which position in the entire observation target is located and which part is being observed. There was a problem that it was difficult to grasp. Note that in order to move the viewpoint to a desired position while viewing the endoscopic image, it is necessary to immediately know where the viewpoint is in the observation target.
[0005]
Further, Japanese Patent Application No. 8-76933 filed by the patent applicant of the present application has a problem that only one so-called guide image is displayed correspondingly and no consideration is given to three-dimensionally grasping the viewpoint or line of sight. was there.
The present invention has been made in view of such circumstances, and provides a three-dimensional image display device that can easily recognize the position of the viewpoint of the endoscopic image in the observation target. The purpose is that. It is another object of the present invention to provide a three-dimensional image display apparatus having a guide image that can grasp the position of the viewpoint three-dimensionally.
[0006]
[Means for solving the problems]
  In order to achieve the above object, the present invention sets a viewpoint inside the observation object on the image in order to endoscopically observe the inside of the observation object on the image, and at a position a predetermined distance from this viewpoint. Using a means for setting a projection plane and a plurality of tomographic images or volume images indicating observation objects on the image, and when an arbitrary viewpoint is set by the setting means, the respective tomographic images are projected from the viewpoint. A 3D image projected onto a surface and shadedAn endoscopic image in which the inside of the observation target is drawn endoscopically from the viewpoint and the viewpoint is not drawn.Cross-sectional images parallel to the xy plane, the yz plane, and the zx plane, respectively, based on the first image creation means to create, the plurality of tomographic images or volume images, and the set viewpoint.OrArbitrary cross-sectional image obtained by cutting the observation target on the image at an arbitrary angleaboveBy drawing the position of the viewpoint, on the cross-sectional imageAnd in the whole observation objectThe position of the viewpoint inWhereA second image creating means for creating a recognizable guide image, and the first image creating means.Endoscopic imageAnd the guide image created by the second image creation means are displayed simultaneously orEndoscopic imageAnd means capable of switching and displaying the guide image.
  Moreover, you may further provide the display means which displays the said endoscopic image and the said guide image simultaneously or switched by the said means.
Further, in order to endoscopically observe the inside of the observation object on the image, a means for setting a viewpoint inside the observation object on the image and setting a projection plane at a predetermined distance from the viewpoint; and When an arbitrary viewpoint is set by the setting means using a plurality of tomographic images or volume images indicating an observation target on the image, the tomographic images are projected onto the projection plane and shaded from the viewpoint. A first image creating means for endoscopically drawing the inside of the observation target from the viewpoint and creating the endoscopic image without drawing the viewpoint; and the plurality of tomographic images On the basis of the image or volume image and the set viewpoint, the cross-sectional image parallel to the xy plane, the yz plane, and the zx plane, or the arbitrary cross-sectional image obtained by cutting the observation object on the image at an arbitrary angle, Viewpoint position By drawing, a second image creating unit that creates a plurality of different types of guide images that can recognize the position of the viewpoint on the cross-sectional image and in the entire observation target, and the first image creating unit You may provide the display means which displays the produced endoscopic image and the guide image produced in multiple numbers by the said 2nd image production means simultaneously or switching.
  Further, the second image creating means calculates a tomographic image in which the viewpoint exists from the plurality of tomographic images, obtains a position of the viewpoint on the tomographic image, and draws on the calculated tomographic image. By doing so, a guide image may be created.
  Further, parameters necessary for reconstruction for creating a guide image are input, a first process for performing a reconstruction operation for creating the guide image, and the three-dimensional coordinates of the observation target are the first From the second processing for storing data indicating which position on the display image of the guide image created in one processing is projected, and from the viewpoint position at the time of reconstruction of the endoscopic image, the second processing A third process for obtaining the position of the viewpoint on the guide image based on the data stored in the process of (4), and a fourth process for drawing the position of the viewpoint on the guide image, The guide three-dimensional image is reconstructed by the second image creating means, and the guide three-dimensional image is arbitrarily rotated by repeatedly executing the first to fourth processes. May be displayed.
  Further, the setting of the position of the viewpoint by the setting means may be performed on either the display screen of each cross-sectional image or the display screen of the endoscopic image.
[0007]
According to the present invention, the first image creating means creates a three-dimensional image as if the inside of the observation target is observed endoscopically from a certain viewpoint, and the second image creating means observes the viewpoint. A guide image is created so that the position inside the target can be grasped. Then, the display means displays a three-dimensional image indicating an endoscopic image and a guide image simultaneously or by switching. As a result, an endoscopic image can be obtained, and the position of the viewpoint of the endoscopic image in the observation target can be grasped by the guide image.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of a three-dimensional image display device according to the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a flowchart showing an outline of processing in a 3D image display apparatus with a guide image according to the present invention.
[0009]
In the figure, in step 1, an endoscopic image is reconstructed from the three-dimensional original image (tomographic image) showing the observation target by the central projection method.
Here, a method for reconstructing an endoscopic image by central projection will be described.
First, coordinate conversion by center projection will be described. When each tomographic image is projected onto the projection plane by central projection, the pixel coordinates of each tomographic image are converted to coordinates on the projection plane as follows.
[0010]
In the example shown in FIG. 10, in order to simplify the explanation, the coordinate system is taken so that the projection plane 6 and the tomographic image 8A, and further the xy plane are parallel to each other. In FIG. 10, x, y, z are axes of the three-dimensional coordinate system (x, y, z), e point (x1, y1, d1) is the position of viewpoint e, and P point (X, Y) is projected. A point on the surface (corresponding to the display screen) 6 and an S point (x0, y0, d0) intersect with a straight line 7 passing through the e point (x1, y1, d1) and the P point (X, Y) and the tomographic image 8A. Is a point.
[0011]
D can be arbitrarily set at the position of the projection plane 6 (on the z axis).
d0 is the position of the tomographic image 8A (on the z axis) and is determined at the time of measurement.
d1 is the z coordinate of the viewpoint e.
According to this, the following equation holds.
[0012]
[Expression 1]
X = {(D−d1) / (d0−d1)} × (x0−x1) + x1 (1)
[Expression 2]
Y = {(D−d1) / (d0−d1)} × (y0−y1) + y1 (2)
[Equation 3]
x0 = {(d0−D) / (d1−D)} × (x1−x) + X (3)
[Expression 4]
y0 = {(d0−D) / (d1−D)} × (y1−y) + Y (4)
When a projected image is displayed on a display screen (not shown) corresponding to the projection plane 6 in a vertical 512 pixel × horizontal 512 pixel, X and Y take values from −256 to +256. On the tomographic image 8A of d0 for each X and Y, x0 and y0 are determined by the above equations (3) and (4), and which point should be projected. Since there are a plurality of tomographic images 8A and a plurality of d0, a plurality of points x0 and y0 to be projected are determined for a set of X and Y.
[0013]
In the same coordinate system, tomographic images 8B to 8E are prepared in addition to the tomographic image 8A, and a diagram viewed from the y-axis direction is shown in FIG. In FIG. 11A, tomographic images 8A to 8E are tomographic images obtained at equal intervals in the same direction with respect to the same object (in the illustrated example, they are equal intervals, but are not necessarily equal intervals). In the tomographic image 8B, the organ regions B1, B2, and B3 are emphasized. When organ regions B1, B2, and B3 are projected onto the projection surface 6, B1 ', B2', and B3 'are obtained. Similarly, when organ regions C1 and C2 of the tomographic image 8C are projected onto the projection plane 6, C1 'and C2' are obtained. Here, when writing projection data (here, B1 ′, B2 ′, B3 ′; C1 ′, C2 ′) into a display memory (not shown), in order to produce a three-dimensional effect, the projection data is viewed from the viewpoint e. Projection data existing farther away is written first, and projection data closer to it is overwritten later. Accordingly, here, since the projection data B1, B2, and B3 are located farther from the viewpoint e than the projection data C1 and C2, the projection data B1 ′, B2 ′, and B3 ′ are written first, and the projection data C1 ′. , C2 'will be overwritten later. In FIG. 11 (a), the projection data B1 ′, B2 ′, B3 ′; C1 ′, C2 ′ are shown separately from the projection plane 6, but these are written into the display memory and are projected data B1 ′, B2 ', B3'; only because the order of C1 ', C2' has been made easier to understand, the projection data B1 ', B2', B3 'written first and the projection data C1', C2 'overwritten on it are actually Is written on the projection plane 6.
[0014]
FIG. 11B shows a more generalized form than FIG. 11A, and shows an example in which the projection plane and the tomographic image plane are not parallel. In this case, it is necessary to create tomographic images 8a, 8b, 8c... Directed to a plane parallel to the projection plane 6 by interpolation calculation from the tomographic images 8A, 8B, 8C. Others are the same as in the case of FIG. Note that b1 '; c1', c2 '; d1' are projection data of the organ regions b1; c1, c2; d1 on the tomographic images 8b, 8c, 8d subjected to the interpolation calculation.
[0015]
FIG. 12 is a diagram for explaining coordinate transformation by central projection when the viewpoint, tomographic image, and projection plane have a more complicated positional relationship, and projection of the S point (x0, z0, y0) on the tomographic image 8. It shows that the result is P point (x, y, z) on the projection plane.
In FIG. 12, when the tomographic image 8 is projected onto the projection plane 6 by central projection, the pixel coordinates of the tomographic image 8 are converted into coordinates on the projection plane 6 as follows.
[0016]
here,
a is the point where the x-axis and the projection plane 6 intersect,
b is the point where the y-axis and the projection plane 6 intersect;
c is the point where the z-axis and the projection plane 6 intersect;
It is. Also,
α is an angle formed by a line projected from the origin to the projection plane 6 on the zx plane and the x-axis.
β is the angle between the perpendicular and the xz plane,
The point e (x1, y1, z1) is the position of the viewpoint e,
P point (x, y, z) is a point on the projection plane (corresponding to the display screen) 6,
S point (x0, z0, y0) is e point (x1, y1, z1) and P point (x, y, z)
The point where the straight line 7 passing through and the tomographic image 8A intersect,
Then, the following equation holds.
[0017]
First, the projection plane 6 is
[0018]
[Equation 5]
(X / a) + (y / b) + (z / c) = 1 (5)
It is represented by
A straight line 7 passing through the point e (x1, y1, z1) and the point P (x, y, z) is
[0019]
[Formula 6]
(X0-x) / (x1-x) = (y0-y) / (y1-y) = (z0-z) / (z1-z) (6)
Given in.
When the projection plane 6 passes through the C1 point (xc1, yc1, zc1),
k1 = sin α
k2 = cos α / sin β
k3 = cos α · cos β / sin β
ai = 1 / a
bi = 1 / b
ci = 1 / c
As
[0020]
[Expression 7]
z = [X * k1-Y * k2-ycl * k3-{(ci * k3 * zcl) / bi} + {(ai * k3 * X) / (bi * cos [alpha])}-{(ai * k3 * xcl). ) / Bi}] / [1-{(ci · k3) / bi} + {(ai · k3 · sin α) / (bi · cos α)}] (7)
[Equation 8]
x = (X−z · sin α) / cos α (8)
[Equation 9]
y = [ycl + {− ci · (z−zcl) −ai · (x−xcl)}] / bi (9)
Here, the C1 point (xcl, ycl, zcl) is, for example, a point where a perpendicular line dropped from the viewpoint e (x1, y1, z1) to the projection plane 6 and the projection plane 6 intersect (between this point and the viewpoint e). The distance is h)
[0021]
[Expression 10]
zcl = z1 + − [h / sqrt {1+ (c²/ A²) + (C²/ B²)}] (“−” Of “zl + −” is when z0 <zcl) (10)
[Expression 11]
xcl = x1 + {c · (z1−zcl) / a} (11)
[Expression 12]
ycl = y1 + {c · (z1−zc1) / b} (12)
May be used.
[0022]
When the projected image is displayed on a display screen (not shown) corresponding to the projection plane 6 in a vertical 512 pixel × horizontal 512 pixel, X and Y take values from −256 to +256. For each X and Y, x and y are determined by the above equations (7), (8), and (9). Since x1, y1, and z1 of the e point are arbitrarily given, the coordinates x0 and z0 of the pixel S point are determined on the tomographic image of y0 = d0 by the following equations (13) and (14).
[0023]
[Formula 13]
x0 = {(d0−y) / (y1−y)} × (x1−x) + x (13)
[Expression 14]
x0 = {(d0−y) / (y1−y)} × (z1−z) + z (14)
Since there are a plurality of tomographic images and a plurality of d0, a plurality of points x0 and y0 to be projected are determined for one set of X and Y.
[0024]
Note that R in FIG. 12 indicates the distance from the viewpoint e to the S point, and this R is a parameter for obtaining the pixel value (luminance) of the P point. The pixel value at point P is proportional to a value obtained by subtracting R from the maximum value Rmax of the set pixel value (luminance). Since the P point corresponds to the (η, ξ) point on the display memory, the pixel value is stored at the (η, ξ) point.
[0025]
The coordinate conversion as described above is performed for all points on the projection plane 6 corresponding to the display screen. This is performed for all tomographic images 8. Furthermore, it may be performed on a three-dimensional image that is a constructed result image, or may be performed on one tomographic image before construction. When the position and the projection plane of the viewpoint e are set in this way, a three-dimensional image (endoscopic image) can be reconstructed. Note that shading of the endoscopic image is performed based on the size of each pixel value stored in the display memory.
[0026]
When the endoscopic image reconstruction calculation is performed as described above in step 1 of FIG. 1, the position (x, y, z) of the viewpoint e used for the reconstruction calculation in step 1 is saved (step 2). ).
Next, in step 3, a guide image is created. As the guide image, for example, one tomographic image, an xy plane, a yz plane, a cross-sectional image parallel to the zx plane, an arbitrary cross-sectional image obtained by cutting an observation target at an arbitrary angle, and a three-dimensional image are conceivable. Note that this three-dimensional image is reconstructed with a field of view that allows the positional relationship of viewpoints to be easily grasped.
[0027]
After obtaining the guide image in step 3, the viewpoint position on the guide image is obtained from the viewpoint position (x, y, z) saved in step 2, and the position is drawn so that the position can be visually recognized.
Step 4 displays an endoscopic image obtained as a result of calculation in Step 1, and Step 5 displays a guide image created in Step 3. The above process is repeated every time the viewpoint is moved, and the position of the viewpoint is presented to the operator.
[0028]
Next, a guide image creation procedure and a screen configuration example for displaying each image will be described.
FIG. 2 is a flowchart showing a guide image creation procedure when a tomographic image perpendicular to the body axis direction is used as a guide image. FIG. 3 is a diagram showing an example of the relationship between the coordinate system and a plurality of tomographic images, viewpoints, and projection planes during reconstruction.
[0029]
In FIG. 2, a step 11 specifies a tomographic image in which a viewpoint exists from coordinates corresponding to the body axis direction. Here, the coordinates corresponding to the body axis direction are y coordinates when tomographic images are stacked in the y-axis direction.
Now, as shown in FIG. 3, if the coordinate axis corresponding to the body axis direction is y, the tomographic image in which the viewpoint exists is Mth, the total number of tomographic images is N, and the constant that can be determined from the resolution is S, Since the composition calculation uses the origin of the coordinate system as the center of the observation target (N / 2), the y-coordinate value of the tomographic image where the viewpoint exists is expressed by the following equation:
[0030]
[Expression 15]
y = (N / 2−M + 1) * S (15)
It becomes. This equation (15) is the following equation:
[0031]
[Expression 16]
M = N / 2 + 1−y / S (16)
Can be rewritten. Therefore, by substituting the y coordinate of the viewpoint position (x, y, z) into the above equation (16) and obtaining M, it can be seen that the viewpoint exists on the Mth tomographic image.
[0032]
Step 12 in FIG. 2 obtains the position of the viewpoint on the tomographic image specified as described above from the position (x, z) of the viewpoint. In FIG. 3, the viewpoint position (x, z) is a coordinate value with the image center as the origin. The position coordinates when drawing the image of the viewpoint are converted so as to correspond to the origin since the upper left of the image is the origin.
In step 13, the viewpoint position obtained in step 12 is drawn on the guide image (tomographic image) obtained in step 11.
[0033]
FIG. 6 shows a screen configuration example in which an endoscopic image and the guide image (tomographic image) are displayed on a monitor screen.
The operator can grasp the position of the viewpoint of the endoscopic image from the guide image shown in FIG. 6, and refers to the guide image when moving the viewpoint to a desired position while viewing the endoscopic image. can do.
[0034]
Next, an example of a method for setting a viewpoint (a method for moving the viewpoint) will be described.
The viewpoint of the endoscopic image displayed in FIG. 6 is the center position of the display screen and is in front of the screen. When the viewpoint is moved up, down, left, and right, and back and forth, for example, a cursor indicating the position in the display screen is moved with the mouse and clicked to set the amount of movement of the viewpoint up, down, left, and right. When moving the viewpoint back and forth, the position of the viewpoint on the display screen is set as described above, and then the amount of movement of the viewpoint in the front-rear direction is set by moving the mouse up and down.
[0035]
After the viewpoint position is set in this manner, the processing shown in FIG. 1 is executed to create new endoscopic images and guide images, and these images are displayed. Then, when the position of the viewpoint is designated again as described above using the new endoscopic image and the guide image, a further new endoscopic image and guide image are created based on the position of the viewpoint. These images are displayed. By sequentially moving the viewpoint position in this manner, the viewpoint can be moved to a desired position inside the observation target.
[0036]
FIG. 4 is a flowchart showing a guide image creation procedure when a cross-sectional image parallel to the xy plane, the yz plane, and the xz plane is used as a guide image.
In step 21, cross-sectional images that pass through the viewpoint positions (x, y, z) saved in step 2 of FIG. 1 and are parallel to the xy plane, yz plane, and xz plane in the coordinate system of FIG. 3 are obtained. These cross-sectional images become guide images. Step 22 determines the position of the viewpoint on each cross-sectional image. Step 23 draws the position of the viewpoint on each cross-sectional image.
[0037]
FIG. 7 shows a screen configuration example in which an endoscopic image and the guide image (each cross-sectional image) are displayed on a monitor screen.
As shown in the figure, the viewpoint position (x, y) can be grasped from a cross-sectional image parallel to the xy plane, and the viewpoint position (y, z) can be grasped from a cross-sectional image parallel to the yz plane. The viewpoint position (x, z) can be grasped from a cross-sectional image parallel to the xz plane.
[0038]
The viewpoint position may be set on the display screen of each cross-sectional image. For example, the position (x, y) of the viewpoint is changed by performing an operation of moving the position of the viewpoint drawn on the display screen of the cross-sectional image parallel to the xy plane on the display screen. According to this, the viewpoint can be set to a desired position inside the observation target relatively quickly. Note that when the position of the viewpoint is set more accurately or when the position of the viewpoint is moved little by little, it is preferable to use the display screen of the endoscopic image as described above.
[0039]
Furthermore, the cross-sectional image used as the guide image is not limited to the cross-sectional image parallel to the xy plane, the yz plane, or the xz plane, and may be an arbitrary cross-sectional image that passes through the position of the viewpoint and cuts the observation target at an arbitrary angle. As this arbitrary cross-sectional image, a cross-sectional image orthogonal to the line-of-sight direction when viewing the observation object from the viewpoint, a cross-sectional image parallel to the line-of-sight direction, etc. are conceivable. It can be automatically set according to the setting.
[0040]
FIG. 5 is a flowchart showing a procedure for creating a guide image when a three-dimensional image is used as a guide image.
In step 31, parameters necessary for reconstruction for creating a guide image are input, and in step 32, reconstruction calculation for creating a guide image is performed. Examples of the method for reconstructing the guide image (three-dimensional image) include surface rendering and volume rendering.
[0041]
In step 33, the position where the three-dimensional coordinates (x, y, z) to be observed are projected on the display image (X, Y) of the guide image created in step 32 is stored.
In step 34, from the viewpoint position at the time of endoscopic image reconstruction (the viewpoint position (x, y, z) saved in step 2 of FIG. 1), based on the data saved in step 33, The position of the viewpoint on the guide image is obtained.
[0042]
In step 35, the position of the viewpoint is drawn on the guide image.
The guide image can be arbitrarily rotated by the operator. When the guide image is rotated, the processing from step 32 to step 35 is repeated for each rotation position. Note that the rotation instruction methods include a mouse drag method, a numerical value input method, and a scale movement method.
[0043]
FIG. 8 shows a screen configuration example in which an endoscopic image and the guide image (three-dimensional image) are displayed on a monitor screen.
As shown in the figure, the position of the viewpoint drawn on the guide image can be grasped only on the position of the guide image, and the position of the viewpoint in the depth direction (direction orthogonal to the paper surface in FIG. 8) is unknown. However, by rotating the guide image, the position of the viewpoint inside the observation target can be grasped.
[0044]
The various guide images described above can be freely switched and displayed according to the intention of the operator, and a plurality of guide images can be displayed simultaneously. For example, as shown in FIG. 13, a three-dimensional first guide image and a tomographic second guide image are displayed simultaneously. Further, an arrow can be displayed on the guide image from the viewpoint position in the line-of-sight direction, and the position of the viewpoint and the line-of-sight direction can be displayed simultaneously. Further, the drawing showing the position of the line of sight can be arbitrarily changed to a shape that is easy to see, such as ◯ and X.
[0045]
In this embodiment, the endoscopic image and the guide image are displayed on the same screen of the monitor. However, the present invention is not limited to this, and the display may be switched.
FIG. 9 is a block diagram showing a hardware configuration example of the guide image-added three-dimensional image display apparatus according to the present invention.
[0046]
As shown in the figure, this three-dimensional image display device with a guide image mainly includes a magnetic disk 41, a main memory 42, a central processing unit (CPU) 43, a display memory 44, a CRT monitor 45, and various types. The keyboard 46, mouse 47, and mouse controller 48 for inputting operation commands, position commands, and menu selection commands, and a common bus 49 that connects these components.
[0047]
The magnetic disk 41 stores a plurality of tomographic images, an image reconstruction program, a guide image creation program, and the like, and the main memory 42 stores a control program for the apparatus and is provided with an arithmetic processing area and the like. ing.
The CPU 43 reads a plurality of tomographic images and various programs, creates an endoscopic image, a guide image, and the like using the main memory 42, sends image data indicating the created image to the display memory 44, and outputs a CRT. It is displayed on the monitor 45.
[0048]
【The invention's effect】
As described above, according to the present invention, the guide image in which the viewpoint position of the endoscopic image can be recognized is displayed at the same time as the endoscopic image or by switching, so that the viewpoint of the endoscopic image is displayed. It is possible to easily recognize the position of the observation position on the observation target, thereby facilitating the movement of the viewpoint.
[Brief description of the drawings]
FIG. 1 is a flowchart showing an outline of processing in a 3D image display apparatus with a guide image according to the present invention.
FIG. 2 is a flowchart showing a guide image creation procedure when a tomographic image perpendicular to the body axis direction is used as a guide image;
FIG. 3 is a diagram illustrating an example of a relationship between a coordinate system, a plurality of tomographic images, a viewpoint, and a projection plane at the time of reconstruction.
FIG. 4 is a flowchart illustrating a procedure for creating a guide image when a cross-sectional image parallel to the xy plane, the yz plane, and the xz plane is used as a guide image;
FIG. 5 is a flowchart illustrating a procedure for creating a guide image when a three-dimensional image is used as a guide image.
6 shows a screen configuration example in which an endoscopic image and a guide image (tomographic image) created by the procedure shown in FIG. 2 are displayed on a monitor screen.
7 shows a screen configuration example in which an endoscopic image and a guide image (each cross-sectional image) created by the procedure shown in FIG. 4 are displayed on a monitor screen.
8 shows an example of a screen configuration in which an endoscopic image and a guide image (three-dimensional image) created by the procedure shown in FIG. 5 are displayed on a monitor screen.
FIG. 9 is a block diagram illustrating a hardware configuration example of a 3D image display apparatus with a guide image according to the present invention.
FIG. 10 is a diagram for explaining conversion of tomographic image pixel coordinates to coordinates on a projection plane in an endoscopic image construction method;
FIG. 11 is a diagram for explaining conversion of pixel coordinates into coordinates on a projection plane for a plurality of tomographic images.
FIG. 12 is a diagram for explaining coordinate conversion by central projection when a viewpoint, a tomographic image, and a projection plane have a more complicated positional relationship;
13 shows an example of a screen configuration in which an endoscopic image and the guide images of FIGS. 6 and 7 are displayed on a monitor image. FIG.
[Explanation of symbols]
6 ... Projection plane
8, 8A-8E, 8a-8e ... Tomographic image
41 ... Magnetic disk
42 ... Main memory
43 ... CPU
44 ... Display memory
45 ... CRT monitor
46 ... Keyboard
47 ... Mouse
48 ... Mouse controller
e ... Viewpoint

Claims (6)

A means for setting a viewpoint in the observation object on the image in order to endoscopically observe the inside of the observation object on the image and setting a projection plane at a predetermined distance from the viewpoint;
When an arbitrary viewpoint is set by the setting means using a plurality of tomographic images or volume images indicating the observation target on the image, the tomographic images are projected onto the projection plane and shaded from the viewpoint. A first image creating means for endoscopically drawing the inside of the observation object from the viewpoint and creating an endoscopic image that does not draw the viewpoint ;
Based on the plurality of tomographic images or volume images and the set viewpoint, cross-sectional images parallel to the xy plane, the yz plane, and the zx plane, respectively, or an arbitrary cross-sectional image obtained by cutting the observation target on the image at an arbitrary angle above, by drawing the position of the viewpoint, and the second image forming means for position of the viewpoint in within the entire cross-sectional image on and the observation target is to create a recognizable guide image,
The endoscopic image created by the first image creating means and the guide image created by the second image creating means are simultaneously displayed or switched between the endoscopic image and the guide image. Means that can be
A three-dimensional image display device. The three-dimensional image display apparatus according to claim 1, further comprising display means for simultaneously displaying or switchingly displaying the endoscopic image and the guide image by the means. A means for setting a viewpoint in the observation object on the image in order to endoscopically observe the inside of the observation object on the image and setting a projection plane at a predetermined distance from the viewpoint;
When an arbitrary viewpoint is set by the setting means using a plurality of tomographic images or volume images indicating the observation target on the image, the tomographic images are projected onto the projection plane and shaded from the viewpoint. A first image creating means for endoscopically drawing the inside of the observation object from the viewpoint and creating an endoscopic image that does not draw the viewpoint ;
Based on the plurality of tomographic images or volume images and the set viewpoint, cross-sectional images parallel to the xy plane, the yz plane, and the zx plane, respectively, or an arbitrary cross-sectional image obtained by cutting the observation target on the image at an arbitrary angle above, by drawing the position of the viewpoint, and the second image forming means for forming a plurality of guide images with different position of the viewpoint of types recognizable in within the whole on and the observation target the cross-sectional image ,
Display means for displaying an endoscopic image created by the first image creating means and a plurality of guide images created by the second image creating means simultaneously or by switching;
A three-dimensional image display device comprising: The second image creation means calculates a tomographic image in which the viewpoint exists from the plurality of tomographic images, obtains the position of the viewpoint on the tomographic image, and draws on the calculated tomographic image. To create a guide image,
  The three-dimensional image display device according to any one of claims 1 to 3. Parameters necessary for reconstruction to create a guide image are entered,
A first process for performing a reconstruction operation for creating the guide image;
A second process for storing data indicating which position on the display image of the guide image created in the first process the three-dimensional coordinates of the observation target;
A third process for determining the position of the viewpoint on the guide image based on the data stored in the second process from the viewpoint position at the time of reconstruction of the endoscopic image;
And a fourth process for drawing the position of the viewpoint on the guide image, and the second image creating means reconstructs a guide three-dimensional image, and the guide three-dimensional image is The display is arbitrarily rotated by repeatedly executing the first to fourth processes. To be
The three-dimensional image display apparatus according to claim 1, wherein the three-dimensional image display apparatus is a display apparatus. The setting of the position of the viewpoint by the setting means can be performed either on the display screen of each cross-sectional image and on the display screen of the endoscopic image.
The three-dimensional image display device according to any one of claims 1 to 5, wherein

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