JP2001104293A - Three-dimentional imaging display equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide three-dimensional imaging display equipment independent of x-ray CT equipment that prepares and displays three-dimensional images using projection data collected by x-ray CT equipment without using two-dimensional imaging data reconstructed by x-ray CT equipment. SOLUTION: Convolution data are prepared by convolution treatment of projection data using the projection data recorded in portable recording media by x-ray CT equipment and information obtained at data collection. Imaging three-dimensional voxel is prepared by back projection processing to the three- dimensional voxel domain indicated to the data. The three-dimensional voxel is prepared using this imaging three-dimensional voxel and parameters decided in plural number of interested domains. By performing three-dimensional imaging processing such as volume rendering on the three dimensional voxel, the independent three-dimensional imaging display equipment is provided that prepares and displays three-dimensional images using three-dimensional data directly reconstructed from projection data without using two-dimensional data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional image display device independent of an X-ray CT apparatus, and an image collected by the X-ray CT apparatus without using two-dimensional image data reconstructed by the X-ray CT apparatus. Using the projection data before reconstruction, a convolution operation process of this projection data and a back projection process to a specified three-dimensional space, and a separation device equipped with means for performing three-dimensional imaging on the result The present invention relates to a three-dimensional imaging device.

[0002]

2. Description of the Related Art In an X-ray CT apparatus, the X-ray
By rotating the X-ray source around the subject in order to obtain a tomographic X-ray image, the subject lying in the rotation axis direction is irradiated with X-rays from multiple directions. The X-ray transmitted through the subject is converted into a current by the X-ray detector. This current is converted into digital data by a data collection circuit. The data is subjected to a detector characteristic correction process, a pre-process, and a reconstruction calculation process to create two-dimensional image data of a cross section of the subject. This is subjected to image processing for display and displayed on the image display device.

[0003] In an X-ray CT apparatus, in order to obtain X-ray tomographic images of a plurality of cross sections of a subject, two-dimensional image data of the plurality of cross sections of the subject are moved by moving the position of a bed on which the subject is mounted. get. The images of the plurality of cross sections are observed by displaying them side by side on a display device.

In order to facilitate understanding of the three-dimensional structure of the subject, a three-dimensional image processing such as volume rendering is performed using the two-dimensional image data having a plurality of cross sections to create a three-dimensional image. That is being done. In a conventional X-ray CT apparatus, since the cross-section interval is larger than the pixel interval in the cross section, the accuracy of the three-dimensional image is not better in the direction orthogonal to the cross section than in the cross section.

In recent years, with the spread of helical scan CT, it has become possible to create image data reconstructed with a finer cross section interval than conventionally performed. By using the image data reconstructed at the fine cross-section intervals, the accuracy of the three-dimensional image is greatly improved.

In recent years, in order to improve the utilization rate of X-rays and to collect necessary data in a short time, a multi-row X-ray detector is used to collect data at a plurality of positions at the same time. Line CT devices have been developed.

In the conventional X-ray CT apparatus, "acquisition of X-ray data"-"pre-processing of collected data"-"image reconstruction processing" are performed in the same apparatus as a series of processes. . Then, a three-dimensional image is created using two-dimensional image data obtained as a result of the image reconstruction processing.

[0008] Workstations for creating three-dimensional images using CT image data are widely used. In these apparatuses, a three-dimensional image is created using two-dimensional image data obtained by an X-ray CT apparatus.

FIG. 9 is a block diagram showing a conventional example.
The outputs of the four rows of detectors 14 are converted to digital data by a data collection circuit 15. The arithmetic processing unit 2 performs pre-processing and reconstruction processing on this data to create two-dimensional image data. Then, image processing for display is performed, and the image is displayed on the image display device 3. The data storage device 21 stores the two-dimensional image data obtained as a result of the reconstruction process in the portable storage medium 5.
To record. The three-dimensional image display device 6 is a portable recording medium 5
A three-dimensional image is created using the two-dimensional image data recorded in. After performing inter-slice interpolation processing on the two-dimensional image data read from the portable recording medium 5, three-dimensional voxel data is constructed. A three-dimensional image processing such as volume rendering is performed on the three-dimensional voxel data to create and display a three-dimensional image.

From the standpoint of creating a three-dimensional image,
There are different requirements for two-dimensional image data for diagnostic purposes and two-dimensional image data as a material for creating three-dimensional images. Ideally, three-dimensional image data is used using two-dimensional image data for diagnostic purposes. It is desired to create a three-dimensional image using two-dimensional image data reconstructed for the purpose of creating a three-dimensional image instead of creating a three-dimensional image.

However, in reality, as described above, “acquisition of X-ray data” — “pre-processing of acquired data” —
"Image reconstruction processing" is the same X
Since the processing is performed by the X-ray CT apparatus, in addition to the processing of reconstructing the two-dimensional image data for diagnosis, the processing of reconstructing the two-dimensional image data for creating a three-dimensional image is performed at the point of loading the X-ray CT apparatus. The reality is that it is difficult to realize from.

Until now, “collection of X-ray data”, “pre-processing of collected data”, and “reconstruction processing” have the same X-ray CT.
It is performed as a series of processes on the device, and it is not routinely performed to separate these processes on the way and perform them on another workstation. The main reason is that "pre-processing of collected data" which corrects the sensitivity and linearity of sensitivity of the unit detectors constituting the X-ray detector for the projection data collected in the "collection of X-ray data" process. However, this requires various data for correction in order to correct the sensitivity and linearity of sensitivity of the unit detector, and acquisition of collected data in order to perform “reconstruction processing”. Since a large number of parameters, such as the cross-sectional position, the collection angle, and the collection time at the time, are required, in order to perform reconstruction processing by the separation device, the information is passed to the separation device together with the collected data. A mechanism is required, but this mechanism has not been developed.

[0013]

The problem to be solved by the present invention is that "X
"Acquisition of X-ray data" is performed by an X-ray CT apparatus, and "Pre-processing of acquired data" and "Reconstruction processing" suitable for 3D images are performed on an independent 3D image display device separate from the X-ray CT apparatus.
And a three-dimensional image display device for creating and displaying a three-dimensional image using the result.

[0014]

According to the present invention, there is provided a stand-alone three-dimensional image display device for recording projection data of a subject and information at the time of data collection on a portable recording medium. Means for acquiring projection data recorded on a portable recording medium and information at the time of data collection by an X-ray CT apparatus comprising: means for performing pre-processing and convolution processing of the projection data; and specifying a reconstruction area. Means for performing back-projection processing of the convolution data on the image three-dimensional voxel region specified by the means, defining a region and a value range occupied by a plurality of objects of interest in the image three-dimensional voxel, and for each object of interest A means for setting the opacity and color corresponding to the three-dimensional voxel value, and calculating from the three-dimensional voxel value and the opacity for each object of interest By providing means for mapping values into one three-dimensional table and means for performing three-dimensional imaging processing on the values of the three-dimensional table, it is possible to use two-dimensional image data reconstructed from projection data. 3D images can be created and displayed using the image 3D data directly reconstructed from the projection data without the need.

In order to solve the above-mentioned problems, a stand-alone three-dimensional image display device according to the present invention uses an X-ray CT apparatus having means for transferring projection data of a subject and information at the time of data collection to another device. Means for acquiring the transferred projection data and information at the time of data collection, means for performing pre-processing and convolution processing of the projection data, and means for specifying an image three-dimensional voxel area specified by a means for specifying a reconstruction area. Means for performing back-projection processing of this convolution data, defining the area and value range occupied by multiple objects of interest in the image 3D voxel space, and opacity and color corresponding to the 3D voxel values for each object of interest And mapping the values calculated from the three-dimensional voxel values and opacity for each object of interest into one three-dimensional table Means and means for performing a three-dimensional imaging process on the values of the three-dimensional table, thereby directly reconstructing from the projection data without using the two-dimensional image data reconstructed from the projection data. It is now possible to create and display 3D images using image 3D data.

[0016]

With the three-dimensional image apparatus according to the present invention, "acquisition of X-ray data" is performed by an X-ray CT apparatus, and "pre-processing of collected data" is performed by an independent three-dimensional image apparatus separate from the X-ray CT apparatus. "Reconstruction processing" suitable for 3D images, and the creation and display of 3D images using the results has become possible.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a three-dimensional image display device of an X-ray CT apparatus according to the present invention will be described. FIG. 1 is a schematic diagram showing a configuration of an embodiment of the present invention. In this embodiment, an X-ray CT apparatus of an electron beam scanning system is shown as an example. Electron gun 12
The electron beam 13 emitted from the object is controlled, and the X-ray target 11 arranged annularly around the subject is scanned in 50 ms or 100 ms.

The X-ray generated by the X-ray target is
The light passes through the subject lying on 6 and is converted into a current by the X-ray detector 14. The X-ray detector 14 is a multi-row detector and simultaneously collects data of a plurality of cross sections. Time-series data is obtained by repeatedly performing the electron beam scanning. In addition, by moving the subject lying on the bed 16, data in different spatial regions can be collected in time series.

In this embodiment, as an example, a case where data of four cross sections are collected by four rows of detectors is described. The output of the X-ray detector is converted into digital data by the data collection circuit 15. The arithmetic processing unit 2 performs pre-processing, reconstruction processing, and image processing for display on this data, and displays this on the image display unit 3.

The data storage device 21 records, on the portable recording medium 5, the result of performing the detector characteristic correction on the output of the data collection circuit 15, which is the projection data of the subject, and the information at the time of data collection.

The three-dimensional image display device 6 is a portable recording medium 5
Is a separate type workstation that creates a three-dimensional image by using projection data recorded in the computer. A pre-processing 71 and a convolution processing 72 are performed on the projection data read from the portable recording medium 5. A region for creating a three-dimensional image is set in the three-dimensional voxel space by 73 without reconstructing a two-dimensional tomographic image with respect to the result of the convolution, and back projection is directly performed on this region. Step 74 is performed to create image three-dimensional voxel data. Parameters such as the region and opacity of a plurality of objects of interest are set by 75, and the image three-dimensional voxel value and the value calculated using this parameter are mapped to one three-dimensional voxel, and this three-dimensional voxel is By performing a three-dimensional imaging process 76 such as volume rendering, a three-dimensional image is created and displayed.

FIG. 2 is a block diagram for explaining an embodiment of the present invention. The projection data of the subject is a four-row detector 1
4 and converted by the data collection circuit 15 into digital data. The arithmetic processing unit 2 performs pre-processing and reconstruction processing on the projection data to create two-dimensional image data.
This is subjected to image processing for display and displayed on the image display device 3. The data storage device 21 records the projection data of the subject and information at the time of data collection on a portable recording medium.

The three-dimensional image display device 6 is a portable recording medium 5
A three-dimensional image is created by using the projection data recorded in the data and information at the time of data collection. The pre-processing 71 and the convolution processing 72 are performed on the projection data recorded on the portable medium 5 acquired by the data storage device 61 and the information 81 at the time of data collection to obtain convolution data 83.
Create Three-dimensional voxel region 84 for performing image reconstruction
Is designated by 73. The back projection processing 74 of the convolution data 83 is performed on the area 84 to create image three-dimensional voxel data 85. A parameter 86 is created by defining an area occupied by a plurality of objects of interest in the image three-dimensional voxel space and a value range, and setting opacity and color corresponding to the three-dimensional voxel value for each object of interest. The value calculated from the three-dimensional voxel value 85 and the parameter 86 for each object of interest is mapped onto one three-dimensional voxel, and a three-dimensional voxel 87 having opacity and color as values is created. A three-dimensional imaging process 77 is performed on the obtained value of the three-dimensional voxel 87 to create a three-dimensional image 88, which is displayed. In an independent three-dimensional image display device, a three-dimensional image 88 is created and displayed using image three-dimensional data 85 directly reconstructed from projection data without using two-dimensional image data reconstructed from projection data. It became possible to do.

According to the present invention, a mechanism for integrating projection data necessary for convolution processing and back projection processing and information at the time of collection into one set of data is created.
FIG. 4 shows an example of the structure of the data set.

Reference numeral 101 denotes a collection parameter, which holds parameters relating to collection. Reference numeral 102 denotes data collected by one collection. Here, the acquisition is a series of data acquisition performed for one patient and is composed of a plurality of scans. Reference numeral 103 denotes scan parameters, which hold parameters relating to scanning. Reference numeral 104 denotes data collected by one scan, and data for the number of scans is linked. Here, a scan is not a precise representation of the human body by an X-ray source and a detector, but is data acquisition of one cross section. Reference numeral 105 denotes a projection parameter which holds a parameter relating to projection. Reference numeral 106 denotes data collected by one projection, and in this embodiment, data for 1024 projections are connected. The projection here refers to data collection by one X-ray irradiation from a certain angle direction. 107
Is a column detector parameter and holds a parameter related to the column detector. Reference numeral 108 denotes data collected by one column detector. In this embodiment, data of four column detectors is linked to the number of column detectors. Where the column detector is
This is a column detector which is a unit constituting the detector, and the detector is composed of a plurality of column detectors. Reference numeral 109 denotes a unit detector parameter which holds a parameter relating to the unit detector. Reference numeral 110 denotes data collected by one unit detector, and data of the number of unit detectors is connected. Here, the unit detector is an element detector that is a unit constituting the column detector, and the column detector is configured by a plurality of unit detectors.

FIG. 4 shows an example in which the photographing cross-sectional position of the collected data is shown by the relationship between the scan number, the column detector number and the projection angle. In this example, the number of column detectors is 4, the interval between column detectors is 1 mm, the number of projections is 1024, and the moving distance between scans is 4 mm.
Is shown. As the couch moves, the imaging cross-sectional position changes depending on the projection angle.

FIG. 5 is a diagram showing projection data collected by projection. The projection number is on the vertical axis, the unit detector number is on the horizontal axis, and the column detector number and scan number are in the depth direction. As the projection numbers increase, they are stacked in the vertical axis direction. By repeating the scan, the images are stacked in the depth direction.

FIG. 6A shows a three-dimensional space having, as a value, a unit detector output value of projection data. The x-axis is the unit detector number, the y-axis is the projection number (projection angle), and the z-axis is the scan number single-row detector number.

FIG. 6 (2) shows a three-dimensional space having a value obtained by convolving the unit detector output value as a value. The x-axis is a unit detector number, the y-axis is a projection number (projection angle), and the z-axis is a scan number-row detector number. FIG.
Convolution operation is performed on the unit detector output data of (1) in the direction of the x-axis unit detector number, using the y-axis projection number (projection angle) and the z-axis scan number-column detector number as parameters. It was obtained.

FIG. 6 (3) shows a three-dimensional space having CT values as values. The x axis is a direction from the left hand to the right hand of the imaging section of the subject, the y axis is a direction from above to below the imaging section of the subject, and the z axis is a direction orthogonal to the imaging section of the subject. The value is obtained by back-projecting the convolution data of FIG. 6 (2) into this three-dimensional space.

The three-dimensional space shown in FIG. 6 (3) is set in a three-dimensional space region for creating a three-dimensional image. First the voxel relative to _{(n x, n y, 0} ) surface composed of, 6
The back projection is sequentially performed for each projection number (angle) using the value of the corresponding surface in the convolution data three-dimensional space of (2). In this case, voxel position 18
The imaging section position 183 is determined from the imaging section position 183, and this imaging section position 1
From 83, a corresponding scan number-column detector number 184 is obtained using a conversion table 181. Back projection is performed using the value of the convolution three-dimensional space corresponding to the scan number-column detector number 184.

The photographing section positions are sequentially shifted by the movement of the bed. 7 and 8 are diagrams for explaining the relationship between the position of the voxel plane and the projection data. The vertical axis is the projection number of the projection data, the horizontal axis is the z direction of the bed moving direction, and a graph using the scan number and the column detector number as parameters. The imaging of the unit detectors # 0, # 1, # 2, and # 3. The cross-sectional position is indicated by oblique lines. 7 and 8, when the slice interval is d _s, shows an example in which the bed in one scan move 5d _s. The slice interval d _s, the voxel spacing of the three-dimensional image creating is expressed by d _v. Here, an integer n that satisfies n> _dv / _ds > n-1 (1) is obtained. Symmetrical from the center plane of the voxel, when length d _b of the _base, the length of the top of d _t, consider the trapezoid satisfy the following equation. _{d b = (n + 1)} d s (2) d t = (n-1) d s (3) adding the projection data of the scanning by the multi-row detector trapezoidal as a weighting factor.

FIG. 7 shows a case where _ds is 1, and _dv is 2.5. From equation (1), n = 3, and from equation (2), d _b = (n + 1) _ds = 4, equation (3)
_Dt = (n-1) _ds = 2. For example, consider the position of the voxel plane indicated by A. The scan number and the column detector number are represented as # 0- # 0, and the projection data is represented as Pd (# 0- # 0). At the projection angle of the projection number # 0, back projection is performed by weighting the projection data as described below. Pd (# 1- # 0) × 0.5 + Pd (# 1- # 1) ×
1.0 + Pd (# 1- # 2) × 1.0 + Pd (# 1- #
3) × 0.5 At the projection angle of projection number # 128, back projection is performed by weighting the projection data as described below. Pd (# 1- # 0) × 1.0 + Pd (# 1- # 1) ×
1.0 + Pd (# 1− # 2) × 1.0 At the projection angle of projection number # 256, back projection is performed by weighting the projection data as described below. Pd (# 0- # 3) × 0.5 + Pd (# 1- # 0) ×
1.0 + Pd (# 1- # 1) × 1.0 + Pd (# 1- #
2) × 0.5

Next, the voxel (nx, ny,
The back projection is sequentially performed for each projection number (angle) on the surface configured in 1) using the value of the corresponding surface in the three-dimensional space of the convolution data in FIG. 6 (2). This corresponds to the voxel position indicated by B in FIG. At the projection angle of the projection number # 0, back projection is performed by weighting the projection data as described below. Pd (# 1- # 3) × 1.0 + Pd (# 2- # 0) ×
1.0 + Pd (# 2− # 1) × 1.0 At the projection angle of projection number # 128, back projection is performed by weighting the projection data as described below. Pd (# 1- # 2) × 0.5 + Pd (# 1- # 3) ×
1.0 + Pd (# 2- # 0) × 1.0 + Pd (# 2- #
1) × 0.5 At the projection angle of projection number # 256, back projection is performed by weighting the projection data as described below. Pd (# 1- # 2) × 1.0 + Pd (# 1- # 3) ×
1.0 + Pd (# 2- # 0) × 1.0

FIG. 8 shows that when _ds is 1, _dv is 0.75.
FIG. From equation (1), n = 1, and from equation (2), d _b = (n + 1) _ds = 2, equation (3)
_Dt = (n-1) _ds = 0. For example, consider the position of the voxel plane indicated by A. The scan number and the column detector number are represented as # 0- # 0, and the projection data is represented as Pd (# 1- # 0). At the projection angle of the projection number # 0, back projection is performed by weighting the projection data as described below. Pd (# 1- # 1) × 0.5 + Pd (# 1- # 2) ×
At the projection angle of 0.5 projection number # 128, back projection is performed by weighting the projection data as described below. Pd (# 1- # 1) × 1.0 At the projection angle of projection number # 256, back projection is performed by weighting the projection data as described below. Pd (# 1- # 0) × 0.5 + Pd (# 1- # 1) ×
0.5

Next, the voxel (nx, ny,
The back projection is sequentially performed for each projection number (angle) on the surface configured in 1) by using the value of the corresponding surface in the three-dimensional space of the convolution data in FIG. 6B. This corresponds to the voxel position indicated by B in FIG. At the projection angle of the projection number # 0, back projection is performed by weighting the projection data as described below. Pd (# 1- # 2) × 0.75 + Pd (# 1- # 3) ×
0.25 At the projection angle of projection number # 128, back projection is performed by weighting the projection data as described below. Pd (# 1- # 1) × 0.25 + Pd (# 1- # 2) ×
0.75 At the projection angle of projection number # 256, back projection is performed by weighting the projection data as described below. Pd (# 1- # 1) × 0.75 + Pd (# 1- # 2) ×
0.25

Calculations are performed sequentially, and finally, voxels (n _x ,
( _y , n _max ) of FIG. 6 (2)
The back projection is sequentially calculated for each projection number (angle) using the value of the corresponding surface of the convolution data of the three-dimensional space.

For a spatial region for creating a three-dimensional image,
By this back projection, image three-dimensional voxel data can be created. Since the three-dimensional space region of interest is set first, it is possible to create image three-dimensional data of a desired region without performing interpolation processing of a two-dimensional image.

A three-dimensional image is created by applying three-dimensional image processing such as volume rendering to the image three-dimensional voxel data.

In the above description, data exchange is performed from the X-ray CT apparatus to the three-dimensional image display apparatus using a portable recording medium, but data exchange is performed online using a network. The same applies to the case.

In the above description, an X-ray C having a so-called multi-row detector for simultaneously acquiring projection data of a plurality of cross sections is described.
Although the T apparatus has been described as an example, an X-ray CT apparatus that collects projection data of one cross section and performs a plurality of image processings on the data or a so-called three-dimensional X-ray CT apparatus using a plane detector is described. Can be similarly applied.

In this embodiment, an X-ray CT apparatus has been described as an example. However, the present invention can be similarly used in medical image apparatuses such as an MR apparatus and an ultrasonic apparatus.

[0043]

The three-dimensional image display device according to the present invention has been recorded on a portable recording medium by an X-ray CT apparatus having means for recording the projection data of the subject and information at the time of data collection on the portable recording medium. Using the projection data and information at the time of data collection, pre-processing and convolution processing are performed on the projection data to create convolution data. A back-projection process of the convolution data is performed on the three-dimensional voxel area specified by the means for specifying the reconstructed area to create an image three-dimensional voxel. A parameter is created by means for defining an area occupied by a plurality of objects of interest in an image three-dimensional voxel and a value range, and setting an opacity and a color corresponding to the three-dimensional voxel value for each object of interest. The three-dimensional voxel value and the value calculated from this parameter are mapped to one three-dimensional table. A three-dimensional image is created by performing a three-dimensional imaging process on the values of the three-dimensional table. According to the present invention, in a three-dimensional image display apparatus independent of an X-ray CT apparatus, a three-dimensional image display apparatus using three-dimensional image data directly reconstructed from projection data without using two-dimensional image data reconstructed from projection data is used. Original images can be created and displayed.

The three-dimensional image display apparatus according to the present invention uses the projection data and the information at the time of data collection transferred by the X-ray CT apparatus having means for transferring the projection data of the subject and the information at the time of data collection. Then, pre-processing and convolution processing are performed on the projection data to create convolution data. A back-projection process of the convolution data is performed on the three-dimensional voxel area specified by the means for specifying the reconstructed area to create an image three-dimensional voxel. A parameter is created by means for defining an area occupied by a plurality of objects of interest in an image three-dimensional voxel and a value range, and setting an opacity and a color corresponding to the three-dimensional voxel value for each object of interest. The three-dimensional voxel value and the value calculated from this parameter are mapped to one three-dimensional table. A three-dimensional image is created by performing a three-dimensional imaging process on the values of the three-dimensional table. According to the present invention, in a three-dimensional image display apparatus independent of an X-ray CT apparatus, a three-dimensional image display apparatus using three-dimensional image data directly reconstructed from projection data without using two-dimensional image data reconstructed from projection data is used. Original images can be created and displayed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a three-dimensional image display device according to the present invention.

FIG. 2 is a block diagram illustrating a three-dimensional image display device according to an embodiment of the present invention.

FIG. 3 is a view for explaining a structure of a data set of projection data used for data exchange between the X-ray CT apparatus and the three-dimensional image display apparatus according to the embodiment of the present invention.

FIG. 4 is a view for explaining the relationship among scan numbers, column detector numbers, projection numbers, and tomographic plane positions in projection data according to the embodiment of the present invention.

FIG. 5 shows a projection number, a unit detector number,
FIG. 4 is a diagram for explaining the relationship between a column detector number and a scan number.

FIG. 6 is a view for explaining a relationship among projection data, convolution data, and three-dimensional voxel data according to the embodiment of the present invention.

FIG. 7 is a diagram for explaining the relationship between the position of a voxel surface and projection data, wherein a vertical axis is a projection number, a horizontal axis is a bed moving direction position coordinate, and a graph using a scan number and a column detector number as parameters. FIG.

FIG. 8 is a diagram for explaining the relationship between the position of the voxel plane and the projection data, wherein the vertical axis is the projection number, the horizontal axis is the bed moving direction position coordinate, and the scan number and the column detector number are used as parameters. FIG.

FIG. 9 is a block diagram illustrating a conventional three-dimensional image display device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Data collection part 2 Arithmetic processing part 3 Image display device 4 Operation device 5 Portable recording medium 6 Three-dimensional image display device 11 X-ray target 12 Electron gun 13 Electron beam 14 X-ray detector 15 Data collection circuit 16 Bed 21 Data storage Device 61 Data storage device 62 Image display device 63 Operation device 64 Storage device 71 Preprocessing unit 72 Convolution processing unit 73 Three-dimensional voxel reconstruction area setting unit 74 Back projection processing unit 75 Area / CT value, opacity of target object of interest Color setting unit 76 Opacity / color three-dimensional voxel creation unit 77 Volume rendering processing 81 Calibrated projection data 82 Preprocessed projection data 83 Convolution data 84 Reconstructed region data of three-dimensional voxel 85 Image three-dimensional voxel data 86 Interest Target area / CT value, Brightness / color parameters 87 Opacity / color 3D voxel data 88 3D image data 101 Acquisition parameters 102 Acquisition data 103 Scan parameters 104 Scan data 105 Projection parameters 106 Projection data 107 Detector parameters 108 Column detector data 109 Unit detector parameters 110 Unit detector data 171 Projection data 172 Convolution data 173 Voxel data 174 Projection data coordinate system 175 Convolution data coordinate system 176 Voxel data coordinate system 177 Real world coordinate system 178 Convolution 179 Back projection 180 Voxel position and imaging section position Conversion 181 Conversion of imaging section position and scan number-column detector number 182 Voxel position 183 Imaging section position 184 Scan number-column detector number

Claims (2)

[Claims] 1. An X-ray CT apparatus comprising means for recording projection data of a subject and information at the time of data collection on a portable recording medium, and acquires projection data and information at the time of data collection recorded on the portable recording medium by an X-ray CT apparatus. Means for performing pre-processing and convolution processing of the projection data, means for performing back-projection processing of the convolution data on an image three-dimensional voxel area specified by means for specifying a reconstruction area, Means for defining an area occupied by a plurality of objects of interest in an image three-dimensional voxel and a value range, and setting opacity and color corresponding to the three-dimensional voxel value for each object of interest, and three-dimensional voxel for each object of interest Means for mapping the values calculated from the values and the opacity into one three-dimensional table, and a three-dimensional image for the values in the three-dimensional table Creating and displaying a three-dimensional image using three-dimensional data directly reconstructed from the projection data without using two-dimensional image data reconstructed from the projection data, comprising: means for performing a conversion process A separation type three-dimensional image display device characterized by the following. 2. An X-ray CT apparatus comprising: means for transferring projection data of a subject and information at the time of data collection to another apparatus; Means for performing data pre-processing and convolution processing; means for performing back-projection processing of the convolution data on an image three-dimensional voxel area specified by means for specifying a reconstruction area; Means for defining the area and value range occupied by a plurality of objects of interest, and setting the opacity and color corresponding to the three-dimensional voxel value for each object of interest. Means for mapping the calculated values to one three-dimensional table, means for performing three-dimensional imaging processing on the values of the three-dimensional table, A separation type, wherein a three-dimensional image is created and displayed using three-dimensional data directly reconstructed from projection data without using two-dimensional image data reconstructed from projection data, comprising: 3D image display device.