JP2002245487A - Device and method for image display, image processor, and medical image diagnostic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image display device which makes it easy to grasp the spatial position relation between an arbitrary section and volume data and determine a sectional position in the arbitrary section and can shorten the time needed for diagnosis when a medical image is displayed in three dimensions. SOLUTION: This image display system 100 is equipped with an image processor 1 including a CPU 10 running a program based upon image processing algorithm which fetches at least two pieces of identical or nearly identical volume data regarding three-dimensional image of an object position of a body to be examined, generates a three-dimensional image from one of the at least two pieces of the volume data and an arbitrary section image from the other(s), displaying the three-dimensional image and the arbitrary section image together on a display device 4, and displays a sectional image obtained by viewing the arbitrary section image from the front simultaneously with the three-dimensional image and arbitrary section 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, an image display method, an image processing device, and a medical image diagnostic device. More particularly, the present invention relates to the field of medical images by using an image collecting device such as an ultrasonic diagnostic device. The present invention relates to an image display device that collects image information on a body tissue or the like and displays the image three-dimensionally.
In particular, three-dimensional display of medical images and arbitrary cross-section display (MP
R).

[0002]

2. Description of the Related Art Image display devices for displaying medical images include:
2. Description of the Related Art There is known an apparatus for displaying a three-dimensional image of a three-dimensional image based on image information on a body tissue of a subject obtained by a medical modality such as an ultrasonic diagnostic apparatus and an X-ray CT scanner.

An image display apparatus for displaying a medical image three-dimensionally usually has an MPR (MultiPlanar) as an image processing method for displaying an arbitrary cross section of a three-dimensional image.
Reconstruction) is employed. According to the MPR, for example, an image of an arbitrary cross section set on a projection image based on volume rendering of a three-dimensional image can be displayed. An example of this display is shown in FIG.

In FIG. 11, a projected image IM of a three-dimensional image
An arbitrary cross-sectional image IM showing the position of an arbitrary cross section set on the frame 100 and viewing the arbitrary cross section from the front.
101 can be simultaneously displayed on another screen. In this case, there is also known an image in which a spatial relationship between an arbitrary cross section and a three-dimensional image is schematically displayed by a graphic indicator.

[0005]

However, in the above-described conventional three-dimensional display / arbitrary cross-section display, the position of the arbitrary cross-section is displayed as a frame on the three-dimensional image. It is necessary to search for a desired arbitrary cross-sectional image while moving the line of sight alternately between the frame display and the image display of the arbitrary cross-section. For this reason, skill is required to grasp the spatial positional relationship between the three-dimensional image and the arbitrary cross section, and as a result, it takes time to determine the arbitrary cross section of the region of interest, and the diagnosis time becomes longer. Was.

Further, in the above-described conventional graphic indicator display, the spatial positional relationship between the three-dimensional image and the arbitrary cross-sectional image is known, but since the line-of-sight directions of both are unknown, misdiagnosis may occur in the worst case. There was also.

The present invention has been made in view of such a conventional situation. In a three-dimensional display of a medical image, the spatial positional relationship between an arbitrary cross section and volume data can be easily grasped. It is an object of the present invention to provide an image display device which can easily determine a cross-sectional position of a cross-section and can shorten a time required for diagnosis.

It is another object of the present invention to provide an image display device which makes it easy to grasp the line of sight between a three-dimensional image and an arbitrary cross-sectional image, and is useful for preventing misdiagnosis.

[0009]

SUMMARY OF THE INVENTION The present invention achieves the above object by, for example, displaying three-dimensional ultrasonic images.
A cross-section where the B-mode image is clipped on the three-dimensionally displayed image obtained by combining the B-mode image and the color Doppler image (or a cross-section where the B-mode image is displayed as an arbitrary cross-sectional image) and the arbitrary cross-section A means for interactively rotating / moving an arbitrary cross-section by displaying the cross-sectional image of the cross-section image facing the front on a separate screen, and graphically showing the spatial positional relationship between the arbitrary cross-section and the volume data and the line of sight -It focuses on means for displaying with an indicator or the like. It has been confirmed that these means make it easier to grasp the spatial position between the arbitrary cross section and the volume data, and also to easily determine the cross sectional position of the arbitrary cross section.

The present invention has been completed based on such an idea, and has at least two data acquisition means for acquiring at least two mutually identical or substantially identical volume data relating to a three-dimensional image of a target region of a subject; At least two volumes acquired by the data acquisition means;
Image processing means for creating a three-dimensional image from one of the data and an arbitrary cross-sectional image from the other of the at least two volume data; and a three-dimensional image created by the image processing means.
Combination display means for composing and displaying a two-dimensional image and an arbitrary cross-sectional image thereof, and an arbitrary cross-sectional image created by the image processing means together with the three-dimensional image and the arbitrary cross-sectional image combined and displayed by the composite display means. Display means for simultaneously displaying images.

In the present invention, it is possible to provide a means for displaying a spatial positional relationship between the three-dimensional image and the arbitrary cross-sectional image and a line of sight thereof. In this case, it is possible to use a graphic indicator that schematically shows the spatial positional relationship between the arbitrary cross section and the volume data and the line of sight.

[0012] The display means may include means for displaying, in addition to the cross-sectional image of the arbitrary cross-sectional image viewed from the front, a plurality of cross-sectional images passing through the cross-sectional position of the image.

According to the image display method of the present invention, at least two mutually identical or substantially identical volume data concerning a three-dimensional image of a target region of a subject are acquired, and at least two volume data acquired thereby are acquired. Generating an arbitrary cross-sectional image from one of the three-dimensional image and the other of the at least two volume data; synthesizing and displaying the three-dimensional image generated thereby and the arbitrary cross-sectional image with each other; Simultaneously displaying a cross-sectional image of the arbitrary cross-sectional image created by the image processing means as viewed from the front, together with the displayed three-dimensional image and the arbitrary cross-sectional image.

[0014] An image processing apparatus according to the present invention comprises a storage means for storing first volume data relating to a three-dimensional area in a subject and second volume data different in type from the first volume data; Means for designating an arbitrary cross-section in the three-dimensional area, means for designating a projection direction when generating a three-dimensional image from the volume data, and setting the three-dimensional area in the first volume data to the projection direction Means for generating a first image obtained by aligning a cross-sectional image based on the second volume data with the projection image projected from the first cross-sectional image and synthesizing the arbitrary cross-section, and generating the first cross-sectional image based on the second volume data Means for generating a second image of the second image viewed from the front, and a second image of the second image viewed from the front orthogonal to the cross section of the second image based on the second volume data. Means for generating an image, the second image and the third on the basis of the second volume data
4th section viewed from the front of a section orthogonal to each section of the image
It is characterized by comprising: means for generating an image; and display means for simultaneously displaying the first to fourth images.

In the present invention, corresponding to each of the second and third images, a graphic image representing a polyhedron image representing the three-dimensional region and a surface image representing the position of the cross section is registered and aligned. It is possible to display.

In the present invention, the second and third images are based on the first volume data and the second volume data, and the two-dimensional color distribution of the speed information and the speed information on the B-mode tomographic image. It is possible that the images are superimposed.

[0017] A medical image diagnostic apparatus according to the present invention is provided with the above-described image display apparatus or the image processing apparatus according to the fifth aspect.

An ultrasonic diagnostic apparatus according to the present invention is provided with the above-described image display apparatus or the image processing apparatus according to the fifth aspect.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an image display device, an image display method, an image processing device, and a medical image diagnostic device according to the present invention will be specifically described below with reference to FIGS.

FIG. 1 is a diagram for explaining an outline of the overall configuration of an image display system of the present embodiment (which constitutes the image display device of the present invention).

An image display system 100 shown in FIG. 1 includes two or more identical medical images of a subject obtained by a medical modality (medical image diagnostic apparatus) 101 such as an ultrasonic diagnostic apparatus 110 and an X-ray CT scanner 111. Alternatively, an image processing apparatus (which constitutes the image processing apparatus of the present invention) 1 which fetches and processes substantially the same volume data, a system memory 2 for storing the volume data,
A magnetic disk device 3 for reading / storing the volume data stored in the memory 2 in a file format, a display device 4 for displaying a 3D image, an image of an arbitrary cross section, a graphic indicator and the like created by the image processing device 1 An input device (for example, a keyboard, a keyboard, etc.) for the operator to perform various operations such as setting an arbitrary cross section while watching the display image on the display device 4.
Trackball, mouse, etc.) 5.

The image processing apparatus 1 includes a computer, and includes a CPU 10, a RAM 11, a ROM 1
2. I / F (various input / output interfaces) 13
And other various elements based on the computer architecture. In the ROM 12 or other recording medium (not shown), in addition to various programs based on an image processing algorithm related to a known 3D image display to be executed by the CPU 10, a 3D image display, an arbitrary cross section display, and a graphic indicator display according to the present invention are provided. Various programs based on an image processing algorithm (see below) are mounted in advance.

Next, the overall operation of this embodiment will be described with reference to FIGS.

First, the case of the ultrasonic diagnostic apparatus 110 as the medical modality 101 will be described as an example. In this case, the image display system 100 can be integrally mounted in the ultrasonic diagnostic apparatus 110, or can be applied to an image display apparatus such as a dedicated workstation independent from the ultrasonic diagnostic apparatus 110 or a PC. is there.

In FIG. 2, first, the ultrasonic diagnostic apparatus 11
By the process 0, the ultrasonic probe (one-dimensional array probe) is manually or mechanically moved within a range covering the target part of the subject three-dimensionally, and B-mode image data on the two-dimensional scanning plane of the ultrasonic beam. And B-mode image data including blood flow information are acquired in multiple slices.

Here, the B-mode image data is an ultrasonic image (hereinafter referred to as “B / W (Black / Black)” that reflects the intensity of the ultrasonic wave reflected by the difference in acoustic impedance of the living tissue.
White) image, which represents the tissue structure in the living body and the ultrasonic contrast agent image in the living body. The color image data is based on the velocity information (velocity value, velocity dispersion value, power value) of the moving body, which is obtained from the frequency shift due to the Doppler effect of the ultrasonic echo reflected from the moving body in the subject. Is a two-dimensional distribution image to which colors are assigned, and represents blood flow information and tissue movement information. In this color image, for example, a value of one pixel is composed of a total of 24 bits of data having RGB values each having a luminance accuracy of 8 bits.

Therefore, in the image display system 100, the processing performed by the image processing apparatus 1 causes the ultrasonic diagnostic apparatus 110 to obtain the B /
W image and color image are collected simultaneously (step S
1) Convert all slices into 8-bit values of, for example, 0 to 255 (step S2). At this time, the part without blood flow information is 0. This can be obtained directly from the original blood flow velocity or power value, or can be obtained from a 24-bit color image in the reverse procedure of assigning a color map to the blood flow velocity or power value. .

Next, with respect to the multi-slice image data that has been converted to 8 bits in this manner, the position data (position and position) Angle) The volume data of the B / W image and the color image are individually generated by performing three-dimensional interpolation processing based on the PD (step S4). At this time, the position data PD of each slice is obtained from information on the position and angle of the ultrasonic probe measured by a probe position detecting device (not shown) at the time of multi-slice ultrasonic scanning by the ultrasonic diagnostic device 110.
For example, volume data of a color image can be obtained by performing an interpolation process on a blood flow direction and a velocity or a power value (blood flow vector information) with respect to a probe in accordance with information on a position and an angle of an ultrasonic probe.

The above-described interpolation processing (step S4) is an example in which a multi-slice scan is performed using a one-dimensional array probe as an ultrasonic probe of the ultrasonic diagnostic apparatus 110. For example, a two-dimensional array probe is used. When volume scanning is performed by using the above, since the volume data is directly obtained, the interpolation processing of each slice as described above is not necessarily required.

The volume data obtained as described above is composed of a minimum unit (voxel) of a three-dimensional image having blood flow vector information. Therefore, in the image processing apparatus 1, by performing volume rendering using the volume data, a projection image reflecting the value of each voxel can be constructed.

Therefore, the image processing apparatus 1 has a volume
A projection image (in this example, a color image) of a three-dimensional image by volume rendering projected and displayed by setting opacity to each voxel value of data and a cross-sectional position arbitrarily set by an operator in the volume A three-dimensional image combined with an image of an arbitrary cross section (B / W image in this example) displaying the voxel value is displayed on the display device 4 (step S5). This display example is shown in FIG.

In FIG. 3, a projection image IM2 of a three-dimensional image obtained by synthesizing the image IM1 of an arbitrary cross section and a picture I of the arbitrary cross section are displayed on a four-split screen on the display device 4.
An image IM3 displaying M1 facing the front, and an image I
Images IM4 and IM5 in which two orthogonal cross sections perpendicular to two directions perpendicular to each other of M3 are displayed facing the front, respectively.

Here, the image processing apparatus 1 is displayed on the above-mentioned screen of the display device 4 only by the operation of the operator using the input device 5 such as a trackball, for example, the operation of moving the trackball up, down, left and right. The position of the arbitrary cross section can be rotated, moved, enlarged and reduced, and the four arbitrary cross sectional images IM1, IM3, IM4 and IM5 are interactively changed and displayed on the display device 4 following the cross section position.

The image processing apparatus 1 is displayed on the screen of the display device 4 only by the operation of the operator using the input device 5 such as a trackball, for example, only the vertical and horizontal movement of the trackball. Rotating, moving, and moving the projection image IM2 of the three-dimensional image by volume rendering while maintaining the spatial positional relationship with the arbitrary cross section and the line of sight direction
The arbitrary cross-sectional image IM1 is interactively rotated, moved, enlarged, reduced, and displayed on the display device 4 in accordance with the projection image IM2.

Then, returning to FIG. 3, the image processing apparatus 1
After the composite display of the three-dimensional image and the arbitrary cross-sectional image described above (step S5), it is determined whether or not the cross-sectional position of the arbitrary cross-sectional image has been changed by the rotation, movement, enlargement, or reduction operation of the input device 5 by the operator. (Step S6) If YES (changed), an arbitrary slice image at the changed slice position is displayed (Step S7). After that, various measurements are performed on the target site by using a known image processing algorithm using such an arbitrary cross section. In this case, for example, when the operator operates the input device 5 (presses an operation button, clicks a mouse, operates a trackball, and the like), the length, thickness, and area of a diagnostic site such as a blood vessel or a tumor ,
Shapes such as volume and other measurements can be automatically executed.

As the above-mentioned arbitrary cross-sectional image, it is possible to use a composite display of volume data of a B / W image (tissue information) and volume data of a color image (blood flow information). FIG. 4 shows a processing example in this case.

In FIG. 4, the image processing apparatus 1 sets a predetermined threshold value (10 in the example in the figure) to the voxel value of the volume data of the color image in step 4 described above, and Volume with voxel values of
Only the data is set as a projection target (step S41), and an arbitrary cross-sectional image of a color image having a voxel value equal to or larger than the threshold is displayed on the display device 4 so as to be superimposed on an arbitrary cross-sectional image of the B / W image (step S5a). ).

The image processing apparatus 1 uses a graphic indicator to determine the positional relationship between the three-dimensional image and its cross-sectional image for each image displayed on a different screen (display device 4 or display area). To display. Display examples of this graphic indicator are shown in FIGS.

In FIG. 5, a graphic indicator 20 is displayed for each screen displaying the images IM3 to IM5 having arbitrary cross sections similar to the case of FIG. 3 described above. The graphic indicator 20 includes a cubic frame F1 schematically representing three-dimensional data, and a rectangular frame F2 schematically representing a cross section. Among them, the rectangular frame F2 is displayed in different colors (colors A and B in the example in the figure) on the upper side and the right side of the screen. In accordance with this, each side of the outer peripheral portion of each screen displaying the arbitrary cross-sectional images IM3 to IM5 and each side of the outer peripheral portion of the arbitrary cross-sectional image IM1 on the three-dimensional image IM2 have the same A as the rectangular frame.
The image is displayed so as to be surrounded by the color B and the color B, whereby it is possible to associate the rectangular frame with the cross-sectional image.

As shown in FIG. 6, the outer periphery of the cubic frame F1 is represented by a predetermined color (green in the example in the figure), and a quadrangular pyramid indicating the direction of the three-dimensional data is displayed therein. In this case, regarding the correspondence between the direction of the three-dimensional data and the quadrangular pyramid, for example, the four side surfaces are different from each other by 2
The blue side of the four sides is divided into minus (-) directions of the Z axis of the volume, and the red side of the four sides is the Z axis. The plus (+) direction, the vertex is the minus direction of the Y axis, the bottom is the plus direction of the Y axis, the right half of the four sides is blue, the left half is the red side, and the left half is the minus direction of the X axis. It is possible to set such that the right half of the one side is red and the left half is blue in the positive direction of the X-axis. Other associations are of course possible.

As described above, according to this embodiment, three-dimensional display of medical images, arbitrary cross-section display,
By performing the indicator display, the three-dimensional image and the cross-section image are displayed simultaneously, and the positional relationship between the three-dimensional image and the cross-section becomes easier to grasp on the image, and the rotation, movement, enlargement, and rotation of the cross-section can be performed with a simple operation. Because it can be reduced, it becomes easy to display a desired cross-sectional image from the three-dimensional data,
The diagnosis time can be further reduced.

Also, in this example, the relationship between the three-dimensional image and the cross-sectional image and the line of sight thereof are schematically displayed by a graphic indicator. It is possible to easily grasp the gaze direction and to help prevent misdiagnosis.

By utilizing the advantages of such three-dimensional display, arbitrary cross-section display, and graphic indicator display, various diagnoses corresponding to the diagnostic site of the subject, for example, when the diagnostic site is a blood vessel, the thickness and length of the blood vessel Now, measurement of the size of the tumor and the like becomes easier.

The graphic indicators described above are not limited to those of the present embodiment. For example, as shown in FIG. 7, each screen displaying images IM3 to IM5 having arbitrary cross sections similar to FIG. The present invention can also be applied to a triangular (or arrow-shaped) graphic indicator 21 indicating the line-of-sight direction of an arbitrary cross section corresponding to each.

In this embodiment, the case where two volume data obtained by the same medical modality (such as an ultrasonic diagnostic apparatus) are displayed is described. However, the present invention is not limited to this. It is also possible to display two or more identical or approximately identical volumes from image data collected with different medical modalities. FIG. 8 shows a processing example in this case.

In FIG. 8, the image processing apparatus 1
Volume data (A volume in the example in the figure)
Data and B volume data) (step S11), the two volume data are adjusted to the same coordinates (step S12), and a projection image reflecting the value of each voxel is displayed on the display device 1. (Step S5).

In this example, a composite display of an arbitrary section and a projected image by volume rendering is illustrated as a three-dimensional display, but the present invention can be applied to other three-dimensional displays. This example is shown in FIG.

On the four-split screen on the display device 4 shown in FIG. 9, in addition to the milling-through image IM6 constructed based on the image obtained by the X-ray CT scanner or the like, the line-of-sight direction of the fly-through image IM6 And an image IM7 of a cross section corresponding to the viewpoint position, and images IM8 and IM9 of cross sections perpendicular to the X-axis direction and the Y-axis direction of the cross section of the image IM7 are displayed. At this time, when the operator operates the input device 5 to update the line-of-sight direction and viewpoint position of the fly-through image IM6,
Accordingly, the images IM7 to IM9 of the respective sections are also updated.
In this case, the cross-sectional position of the cross-sectional image IM7 corresponding to the line-of-sight direction and the viewpoint position of the fly-through image IM6 is slightly away from the viewpoint position at which the fly-through image IM6 is displayed, for example, several cm away from the line-of-sight direction. It is also possible to display a cross section a few centimeters or a few centimeters earlier, or to be able to arbitrarily designate a cross section position from an input device.

As shown in FIG. 10, the sectional shape of the image IM1 of an arbitrary cross section on the projected image M2 of the three-dimensional image is transformed from the above-mentioned plane into a curved surface of an arbitrary shape by using the curved surface MPR technique. It is also possible to display an image IM3 in which the cross-sectional image IM1 of the curved surface is directed to the front.

Regarding the display of the blood flow information and the blood flow information vector information, a commonly used maximum intensity projection method (Maximum Intensity Project) is used.
Tion: MIP), minimum intensity projection (Minimum)
Intensity Projection: MinI
P), surface rendering (SurfaceRe)
ndering), a display method such as an integrated projection method, and other display methods suitable for diagnosis.

[0051]

As described above, according to the present invention,
The three-dimensional image and the cross-sectional image are displayed at the same time, so that the positional relationship between the three-dimensional image and the cross-section can be more easily grasped on the image, and the cross-section can be rotated / moved with a simple operation. Thus, it is possible to provide an image display device, an image display method, an image processing device, and a medical image diagnostic device that can easily display a desired cross-sectional image and can further shorten the diagnosis time.

According to the present invention, the relationship between the three-dimensional image and the cross-sectional image and the direction of the line of sight can be displayed by a display means such as a graphic indicator. The direction of the line of sight can be easily grasped, and it is possible to help prevent misdiagnosis.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing a configuration of an image display device according to an embodiment of the present invention.

FIG. 2 is a schematic flowchart illustrating a processing procedure of the image display device.

FIG. 3 is a view for explaining a combined display of a three-dimensional image and an arbitrary cross-sectional image and an orthogonal three-sectional image display according to the arbitrary cross section.

FIG. 4 is a view for explaining an example in which a plurality of volume data are combined and displayed using a threshold value.

FIG. 5 is a view showing a display example of a graphic indicator.

FIG. 6 is a view for explaining the correspondence between graphic indicators and three-dimensional data.

FIG. 7 is a diagram showing another display example of the graphic indicator.

FIG. 8 is a schematic flowchart illustrating a processing procedure when using volume data collected and created by different modalities.

FIG. 9 is a diagram showing a case where three orthogonal cross sections are displayed using a fly-through image as three-dimensional display.

FIG. 10 is a diagram illustrating a case where the shape of an arbitrary cross section is a curved surface.

FIG. 11 is a view for explaining three-dimensional display / arbitrary cross-section display in a conventional example.

[Explanation of symbols]

 Reference Signs List 1 image processing device 2 system memory 3 magnetic disk device 4 display device 5 input device 10 CPU 11 RAM 12 ROM 13 I / F 100 image display system 101 medical modality 110 ultrasonic diagnostic device 111 X-ray CT scanner

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G06T 1/00 290 G06T 15/00 200 5B080 15/00 200 A61B 5/05 380 (72) Inventor Atsuko Sugiyama 1385-1, Higashiyama, Shimoishi-kami, Otawara-shi, Tochigi Pref. Toshiba Nasu Factory (72) Inventor Masahide Ichihashi 1385-1, Higashiyama, Shimoishi-kami, Otawara-shi, Tochigi F-term (reference) 4C093 AA22 AA26 CA23 FF42 FF46 FG08 4C096 AA10 AB39 DC36 DC37 DD02 4C301 CC02 DD01 JC11 KK11 KK17 KK19 KK22 5B050 AA02 BA04 BA06 CA07 DA02 DA07 DA10 EA18 EA19 FA02 FA12 FA19 GA08 5B057 AA07 DB08 CE08

Claims (9)

[Claims] 1. Data acquisition means for acquiring at least two identical or substantially identical volume data of a three-dimensional image of a target region of a subject, and at least two volume data acquired by the data acquisition means Image processing means for creating a three-dimensional image from one of them and an arbitrary cross-sectional image from the other of the at least two volume data; and synthesizing the three-dimensional image created by the image processing means and the arbitrary cross-sectional image. Display means, and display means for simultaneously displaying a three-dimensional image and an arbitrary cross-sectional image synthesized and displayed by the synthetic display means and a cross-sectional image of the arbitrary cross-sectional image created by the image processing means as viewed from the front. An image display device characterized by the above-mentioned. 2. The image display device according to claim 1, further comprising means for displaying a spatial positional relationship between the three-dimensional image and the arbitrary cross-sectional image and a line of sight thereof. Image display device. 3. The image display device according to claim 1, wherein the display unit includes a unit that adds the arbitrary cross-sectional image to a cross-sectional image viewed from the front and displays a plurality of cross-sectional images passing through a cross-sectional position of the image. An image display device comprising: 4. Acquiring at least two identical or substantially identical volume data of a three-dimensional image of a target region of a subject; and acquiring a three-dimensional image and a three-dimensional image from one of the at least two acquired volume data. Creating an arbitrary cross-sectional image from the other of the at least two volume data; synthesizing and displaying the three-dimensional image generated thereby and the arbitrary cross-sectional image; Simultaneously displaying the cross-sectional image of the arbitrary cross-sectional image created by the image processing means as viewed from the front together with the arbitrary cross-sectional image. 5. A storage means for storing first volume data and a second volume data of a type different from the first volume data for a three-dimensional area in a subject, and an arbitrary one in the three-dimensional area. Means for specifying a cross-section, means for specifying a projection direction when generating a three-dimensional image from the volume data, and a three-dimensional area in the first volume data projected onto the projection image from the projection direction, Means for generating a first image obtained by aligning and synthesizing a cross-sectional image based on the second volume data with the arbitrary cross-sectional portion, and a second image of the arbitrary cross-section viewed from the front based on the second volume data Means for generating an image; means for generating a third image of a cross section orthogonal to the cross section of the second image as viewed from the front, based on the second volume data; Means for generating a fourth image in which a cross section orthogonal to each of the cross sections of the second image and the third image is viewed from the front based on the second volume data; and a display for simultaneously displaying the first to fourth images. And an image processing apparatus. 6. A graphic image is displayed corresponding to each of the second and third images, wherein the image of the polyhedron representing the three-dimensional region and the image of the surface representing the position of the cross section are aligned with each other. The image processing apparatus according to claim 5, wherein: 7. The second and third images form a two-dimensional color distribution image of velocity information and velocity information on a B-mode tomographic image based on the first volume data and the second volume data. The image processing apparatus according to claim 5, wherein the image processing apparatus is superimposed. 8. A medical image diagnostic apparatus comprising the image display device according to claim 1 or the image processing device according to claim 5. 9. An ultrasonic diagnostic apparatus comprising the image display device according to claim 1 or the image processing device according to claim 5.