JP2003185601A - Cone ct scanner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cone CT scanner capable of rapidly setting a slice range in repeated constitution processing. <P>SOLUTION: The X-ray fluoroscopic image P of an article W to be observed is displayed on a display device 10c using the memory content of a fluoroscopic data memory means (memory) 9, by issuing a command aiming at performing repeated constitution processing and the set states (C1 and C2) of the slice range are superposed on the fluoroscopic image P to be displayed. By this constitution, the slice range can be rapidly set intuitively in the repeated constitution processing. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an industrial X-ray CT apparatus, and more particularly, to a two-dimensional X-ray of an object to be observed using a cone-shaped X-ray beam. The present invention relates to a so-called cone CT apparatus which collects fluoroscopic information and reconstructs a large number of X-ray tomographic images at once using the information. 2. Description of the Related Art In a cone CT apparatus, generally, as schematically shown in FIG. 3, a two-dimensional X-ray detector 32 is opposed to an X-ray source 31 for outputting a cone-shaped X-ray beam. Are arranged, and a turntable 33 for mounting the object W between them and rotating around a rotation axis Ra orthogonal to the X-ray optical axis L is adopted. A cone-shaped X-ray beam is emitted while being rotated around, and a two-dimensional X-ray fluoroscopic image of the object W is collected in a memory at each minute rotation angle. And the X collected by that one shot
Using the fluoroscopic data, a tomographic image of the observation object W along many xy planes orthogonal to the z-axis can be reconstructed by calculation. In the reconstruction processing of a tomographic image, as shown in FIG. 4, a perspective image P of an object W is displayed on a display, and a z-axis direction for obtaining a tomographic image is displayed on the display screen. There is known a method in which cursors C1 and C2 for setting a range, ie, a slice range, are overlapped and displayed. By adopting this display, it is possible to visually grasp where to slice the object W to be sliced. [0004] By the way, this kind of C
In the T device, after collecting X-ray fluoroscopic data of the observation target W and obtaining a tomographic image, reconstructing a tomographic image in which a desired portion of the observation target W is enlarged using the same data, Reconstruction processing (enlargement reconstruction processing) can be performed. In this reconstruction processing, the operator inputs dimensions, coordinates, and the like based on the previously reconstructed tomographic image. Had to be set. Therefore, there is a problem that it is difficult to quickly set the slice range of the re-reconstruction processing. The present invention has been made in view of such circumstances, and has as its object to provide a cone CT apparatus capable of quickly setting its slice range even during reconstruction processing. In order to achieve the above object, a cone CT apparatus according to the present invention is provided with an X-ray source for outputting a cone-shaped X-ray beam, and is arranged to face the X-ray source. A two-dimensional X-ray detector, a turntable mounted between the two, for mounting an object to be observed and rotating about a rotation axis orthogonal to the X-ray optical axis, and driving the turntable to rotate the X-ray. A fluoroscopic data storage means for storing X-ray fluoroscopic data at a plurality of rotational positions collected by irradiating an X-ray beam from a radiation source onto an object to be observed, and using the storage contents of the fluoroscopic data storage means, Reconstruction processing operation means for obtaining and displaying on the display a tomographic image for each observation along a plane orthogonal to
After the reconstruction processing calculation, a command to execute the reconstruction processing is given, and by setting a slice range in the direction along the rotation axis, the setting is performed using the same data in the perspective data storage means. The above-mentioned re-reconstruction processing is executed in a cone CT apparatus provided with re-reconstruction processing calculation means for obtaining a tomographic image of the object to be observed within the slice range obtained under an arbitrary set magnification and displaying the same on a display. By giving the instruction to perform, the perspective image of the object to be observed is displayed on the display device using the storage contents of the perspective data storage means, and the setting status of the slice range is displayed by being superimposed on the perspective image. It is characterized by having reconfiguration processing range display means. Here, in the present invention, the output of the X-ray detector is used as it is for the fluoroscopic image of the object to be observed, which is displayed on the display by giving a command to execute the reconstruction process.
If there is pixel data that has already been subjected to various correction processes such as enhancement processing in addition to a perspective image using so-called raw data, it is rather preferable to employ a perspective image using the data after the correction process. According to the present invention, at the time of reconstructing a tomographic image, the setting of the slice range is superimposed on the perspective image of the object to be observed, so that the slice range at the time of the reconstructing process is intuitively and quickly set. And achieve the intended objectives. That is, a command is issued to execute a reconstruction process on a tomographic image of an object under observation at a desired magnification using the X-ray fluoroscopic data already collected and stored in the fluoroscopic data storage means. By giving, the perspective image of the observation object using the storage content of the perspective data storage means is displayed,
In addition, a setting state of a slice range to be reconstructed is displayed so as to be superimposed on the perspective image. With this display,
The operator can intuitively and quickly set the slice range during the reconfiguration processing. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an embodiment of the present invention, and is a diagram showing both a schematic diagram showing a mechanical configuration and a block diagram showing an electrical configuration. [0011] The cone beam-shaped X-ray is converted into a horizontal X-ray optical axis L.
A two-dimensional X-ray detector 2 composed of a combination of an image intensifier and a CCD camera, for example, is disposed opposite to an X-ray source 1 that outputs light along the line, and a turntable 3 is provided between them. I have. The turntable 3 mounts the object to be observed W and rotates about a rotation axis Ra along a vertical z-axis direction, and the turntable 3 moves in x- and y-axis directions orthogonal to each other on a horizontal plane. They are mounted on a table moving mechanism 4 which can move independently. In addition, the two-dimensional X
The line detector 2 is also mounted on a detector moving mechanism 5 that can move in a direction along the X-ray optical axis L (x-axis direction). These turntable 3 and table moving mechanism 4,
Each motor (not shown) that is a driving source of the detector moving mechanism 5 is supplied with a drive control signal from a motor control circuit 6 including a driver corresponding to each motor. The X-ray source 1 is driven and controlled by a tube voltage and a tube current supplied from an X-ray controller 7. Also,
Each pixel output of the two-dimensional X-ray detector 2 is
Is taken into the memory 9 via the data sampling circuit 8 each time the data is rotated by a predetermined minute angle. The data sampling circuit 8 is placed under the control of a computer 10 together with the X-ray controller 7 and the motor control circuit 6 described above. The computer 10 includes an attached keyboard 1
0a or the mouse 10b, the object W
The imaging conditions for obtaining the X-ray fluoroscopic data, for example, various parameters such as X-ray conditions and geometric conditions can be set. The X-ray controller 7, the motor control circuit 6, and the data sampling circuit 8 are set according to the set contents. To the control command. The computer 10 has an object W to be observed.
Reconstruction processing calculation for generating a tomographic image of the object W within the set slice range using the X-ray fluoroscopic data of the object W stored in the memory 9 by the photographing, and displaying the tomographic image on the display 10c. And a tomographic image of the object W under arbitrary magnification within an arbitrarily configurable slice range using the same perspective data after the reconstruction processing operation. A program for performing a so-called re-reconstruction processing operation, which is displayed on the display 10c, is installed. When performing the reconstruction processing operation, it is necessary to set the magnification and the slice range of the tomographic image. However, when a command to execute the reconstruction processing is given, the reconstruction processing shown in FIG. 2 is performed. A dialog for setting conditions for the configuration process is displayed on the display 10c. The features of the dialog for setting conditions for the re-reconstruction processing include a display unit Dn for setting numerical values for setting magnification and brightness, and a display area Dn for setting slice areas on the xy plane. Display section D in addition to the display section Da for setting the slice range in the z-axis direction to be subjected to the re-reconstruction processing.
s. The slice range setting display section Ds includes an X-ray fluoroscopic image P of the observation object W using the pixel data from the two-dimensional X-ray detector 2 stored in the memory 9 and an upper part of the slice range. Cursors C1 and C2 indicating the lower limit are displayed in a superimposed manner, and each of the cursors C1 and C2 independently moves in the z-axis direction by operating the keyboard 10a or the mouse 10b, and slices corresponding to the positions of the cursors C1 and C2. The range is set. Accordingly, the operator can set the slice range in which the reconstruction processing is to be performed while viewing the X-ray fluoroscopic image P of the object W, and can quickly and intuitively set the slice range of the reconstruction processing. . After performing the above various settings, the data read switch Sr is clicked, and the reconfiguration start switch Sr is clicked.
By clicking s, the necessary X-ray fluoroscopic data stored in the memory 9 is read out by imaging, and a tomographic image of the object W is set within the set slice range. It is reconstructed based on the set magnification. The pixel data for constructing the X-ray fluoroscopic image P of the object W displayed on the slice range setting display section Ds uses the output of the two-dimensional X-ray detector 2 as it is, The one that has been subjected to the correction processing may be used,
The point is that the object W can be recognized. As described above, according to the present invention, when reconstructing a tomographic image of an object to be observed, a command to that effect is given, whereby a fluoroscopic image of the object to be observed collected at the time of photographing is obtained. Is displayed, and the setting status of the slice range is displayed by a cursor or the like so as to be superimposed on the perspective image, so that the operator can intuitively and quickly set the slice range in which the re-reconstruction process is to be performed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of an embodiment of the present invention, showing both a schematic diagram showing a mechanical configuration and a block diagram showing an electrical configuration. FIG. 2 is an explanatory diagram of an example of a dialog for various settings displayed on a display when performing re-configuration in the embodiment of the present invention. FIG. 3 is a schematic diagram showing an example of the configuration of a cone CT apparatus. FIG. 4 is an explanatory diagram of an example of a slice range setting screen displayed at the time of reconstruction processing in a conventional cone CT apparatus. [Description of Signs] 1 X-ray source 2 2-dimensional X-ray detector 3 Turntable 4 Table moving mechanism 5 Detector moving mechanism 6 Motor controller 7 X-ray controller 8 Data sampling circuit 9 Memory 10 Computer 10a Keyboard 10b Mouse 10c Display C1, C2 Cursor Ds Slice range setting display section P X-ray fluoroscopic image W of the object to be observed W

Claims (1)

Claims: 1. An X-ray source for outputting a cone-shaped X-ray beam, a two-dimensional X-ray detector arranged opposite to the X-ray source,
A turntable that is disposed between these, and that mounts the object to be observed and rotates around a rotation axis orthogonal to the X-ray optical axis;
A fluoroscopic data storage means for storing X-ray fluoroscopic data at a plurality of rotational positions collected by irradiating the object with an X-ray beam from the X-ray source while driving the turntable; Reconstruction processing calculating means for obtaining a tomographic image for each observation object along a plane perpendicular to the rotation axis using the stored contents and displaying the same on a display device, and executing re-reconstruction processing after the reconstruction processing calculation. And by setting a slice range in the direction along the rotation axis, using the same data in the perspective data storage means, a tomographic image of the object within the set slice range is obtained. In a cone CT apparatus provided with a reconstruction processing calculating means for obtaining and displaying on a display under an arbitrarily set magnification, by giving a command to execute the reconstruction processing, A reconstructed processing range display means for displaying a perspective image of the object to be observed on a display using the storage contents of the data storage means, and displaying a setting state of a slice range superimposed on the perspective image. A cone CT apparatus.