WO2023200110A1

WO2023200110A1 - Method for controlling radiography device

Info

Publication number: WO2023200110A1
Application number: PCT/KR2023/002516
Authority: WO
Inventors: 김성규
Original assignee: 주식회사 뷰웍스
Priority date: 2022-04-15
Filing date: 2023-02-22
Publication date: 2023-10-19
Also published as: KR20230147965A

Abstract

The present invention relates to a method for controlling a radiography device. The present invention provides the method for controlling a radiography device which includes an arm supported to be movable up and down and rotatable on a support, a radiation generation unit provided on one side of the arm, and a detector provided on the arm to face the radiation generation unit, the method comprising the steps of: obtaining a first radiation image by controlling the arm, the radiation generation unit, and the detector to a first position; and obtaining a second radiation image having an overlapping region at least partially overlapping the first radiation image, by controlling the arm, the radiation generation unit, and the detector to a second position, wherein it is controlled that as if, in the first and second positions, the radiation generation unit rotates about a reference axis and the detector moves along a reference surface.

Description

Control method of radiography device

The present invention relates to a control method for a radiography device. More specifically, the present invention relates to a method of controlling a radiography device so that a subject to be photographed can be divided and photographed and the divided images can be easily stitched.

Noninvasive medical imaging clinical diagnosis using radiography systems is the most common medical practice. In particular, in order to facilitate the diagnosis of scoliosis, bow leg varus surgery, etc., long-format radiological images that comprehensively show the diagnosis target are needed. For example, full-spine and long-bone are representative long-shaped radiographic images. In order to implement a long-shaped radiology image, the subject to be photographed is divided and photographed, and the divided images are stitched.

In stitching of segmented images, the process of determining overlapping parts (similar parts) of captured segmented images and stitching the segmented images by overlapping the overlapping parts is performed. However, the image similarity judgment process for determining overlapping parts in segmented images requires advanced image processing technology, and a considerable amount of resources and time are consumed in the process of determining and splicing overlapping parts. On the other hand, when shooting a segmented image, distortion may occur in the segmented image due to the positional relationship between the radiation generator that generates and irradiates radiation and the detector that detects the radiation, and when stitching a distorted segmented image, errors in image interpretation may occur. can cause

The purpose of the present invention is to provide a method of controlling a radiographic imaging device to obtain segmented images of an imaging target with easy stitching and minimal distortion.

The present invention includes an arm that is lifted and lowered on a support and rotatable about a first rotation center, a radiation generating unit provided on one side of the arm to be movable relative to the arm in a first direction, and the radiation generating unit. A method of controlling a radiographic imaging apparatus including a detector provided on the arm to face the arm, movable relative to the arm in a first direction, and rotatable about a second rotation center, the arm, the radiation generator, and Acquiring a first radiation image by controlling the detector to a first position; and controlling the arm, the radiation generator, and the detector to a second position to obtain a second radiation image having an overlapping area that at least partially overlaps the first radiation image. and in the second position, the radiation generator rotates about a reference axis, and the detector is controlled as if it moves along the reference plane.

When controlled from the first position to the second position, the arm rotates at a predetermined angle about the first rotation center and is raised or lowered along the support, and the radiation generator is attached to the arm in the first direction. By moving relative to each other, the radiation generating unit at the first position and the second position may be aligned with the reference axis.

Additionally, the detector moves relative to the arm in the first direction and rotates to match the reference plane, so that the detector at the first position and the second position can be positioned on the reference plane.

In one embodiment, at the reference position, the reference plane may be set as a plane perpendicular to the radiation irradiation direction of the radiation generating unit.

In one embodiment, the overlapping area may be calculated by receiving the length of an overlapping portion of the imaging target that overlaps the first radiological image and the second radiological image.

In one embodiment, the length of the overlapping portion of the imaging target that overlaps the first radiological image and the second radiological image may be calculated based on the length of the overlapping area.

Additionally, the method of controlling a radiography apparatus may further include the step of stitching the first radiation image and the second radiation image using the overlapping area.

Meanwhile, the present invention relates to a control method of a radiographic imaging device including a support, an arm supported on the support, and a radiation generator and a detector arranged to face each other on the arm, wherein a plurality of radiation images are connected to each other with an overlapping area. During imaging, the arm, the radiation generator, and the detector are controlled as if the radiation generator rotates about a reference axis and the detector moves along the reference plane.

When capturing the plurality of radiation images, the radiation generating unit may be aligned with the reference axis by rotating and lifting the arm and moving the radiation generating unit relative to the arm in a first direction.

When capturing the plurality of radiological images, the detector may be positioned on the reference plane by rotation and elevation of the arm, and relative movement and rotation of the detector in a first direction with respect to the arm.

Meanwhile, the length of the overlapping area may be related to the length of the overlapping part of the photographing target.

The method of controlling a radiographic imaging apparatus according to the present invention may further include the step of stitching the plurality of radiographic images using the overlapping area.

According to the present invention, there is an advantage in that a segmented image can be acquired by automatically controlling a radiography device, and the entire image can be easily obtained by stitching the obtained segmented images together without complicated image processing.

In addition, according to the present invention, the magnification rate in the overlapping portion between divided images is made uniform, thereby reducing image distortion and preventing errors in image reading.

1 is a diagram showing the configuration of a radiography apparatus for applying the present invention.

FIG. 2 is a diagram illustrating an example of imaging a subject according to a control method of a radiography apparatus according to an embodiment of the present invention.

Figure 3 is a diagram illustrating the result of stitching a plurality of segmented images of a photographing target.

FIG. 4 is a diagram illustrating an overlapping area in a detector in a method for controlling a radiography apparatus according to an embodiment of the present invention.

FIGS. 5A to 5D are diagrams illustrating a process of controlling an arm, a radiation generator, and a detector according to a control method of a radiation imaging device according to an embodiment of the present invention.

Figure 6 is a flowchart showing a control method of a radiography apparatus according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. First, when adding reference signs to components in each drawing, it should be noted that the same components are given the same reference numerals as much as possible even if they are shown in different drawings. Additionally, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description will be omitted. In addition, preferred embodiments of the present invention will be described below, but the technical idea of the present invention is not limited or restricted thereto, and of course, it can be modified and implemented in various ways by those skilled in the art.

The radiography apparatus 1 includes a radiation generator 30 that generates and irradiates radiation, a detector 40 that detects radiation, an arm 20 that supports the radiation generator 30 and the detector 40, and It includes a support 10 that supports the arm 20. In addition, the radiation imaging apparatus 1 further includes a control unit 50 for controlling the positions and imaging of the radiation generating unit 30, the detector 40, and the arm 20. In FIG. 1, the control unit 50 is shown as being provided inside the support 10, etc., but the control unit is provided in another part of the radiography apparatus 1 or outside the radiography apparatus 1 rather than the support 10. It may also be possible. The control unit 50 may be connected to the radiation generator 30, detector 40, and arm 20 by wire or wirelessly. Additionally, an interface unit 60 that inputs information for radiography to the control unit 50 and receives radiography results may be additionally included. The control unit 50 and the interface unit 60 may be connected wired or wirelessly.

The radiation generator 30 is provided on one side of the arm 20, and the detector 40 is provided on the other side of the arm 20. That is, the radiation generator 30 and the detector 40 are arranged on the arm 20 to face each other. As an example of a radiography device with this configuration, a U-Arm type radiography device is known. In FIG. 1 , for convenience of explanation, the arm 20 is shown in the form of a straight beam, but of course, the arm 20 can also be configured to form a curve rather than a straight line.

The radiation generating unit 30 is provided on the arm 20 to be movable in a first direction (x-axis direction in FIG. 1). For example, the radiation generator 30 may be coupled to the first guide 22 movably mounted on the arm 20 in the x-axis direction.

The detector 40 is provided on the arm 20 to be movable in a first direction (x-axis direction in FIG. 1) and rotatable about a second direction (y-axis direction in FIG. 1). For example, the detector 40 may be coupled to the second guide 24 movably mounted on the arm 20 in the first direction and rotatable about the second rotation center C2. In one embodiment, at least some of the radiation generated from the radiation generating unit 30 is always disposed to face a predetermined position of the detector 40, for example, the second rotation center C2 of the detector 40. You can.

The arm 20 is provided to be movable in a third direction (z-axis direction in FIG. 1) on the support 10, and rotatable about a second direction (y-axis direction in FIG. 1). That is, referring to FIG. 1, the arm 20 can rotate about the first rotation center C1, and the arm 20 can move in the vertical direction on the support 10.

The movement and/or rotation configuration of the radiation generating unit 30, the detector 40, and the arm 20 may be implemented by various mechanical mechanisms other than the example shown in FIG. 1. In other words, the arm 20 may be provided in a curved shape rather than the shape shown in FIG. 1 . In addition, the mechanism for moving the radiation generating unit 30 in the first direction and the mechanism for moving the detector 40 in the first direction and rotating in the second direction are the known oil-arm type radiation. It can be implemented by various configurations of the imaging device. Meanwhile, movement of the radiation generating unit 30 and the detector 40 in the first direction may be understood to mean relative movement with respect to the arm 20.

The control method of the radiography apparatus according to the present invention is to control the radiation generator 30 as if irradiating radiation to the imaging object S while rotating at a specific position when dividing the imaging object S, and the detector (40) is characterized in that it is controlled as if it moves in the vertical direction from the rear of the photographing target (S). That is, the movement of the arm 20 of the radiography device shown in FIG. 1 in the z-axis direction, the rotation around the y-axis, and the relative movement of the radiation generating unit 30 with respect to the arm 20 (in the x-axis direction in FIG. 1 movement), relative movement of the detector 40 to the arm 20 (movement in the x-axis direction in Figure 1) and rotation around the y-axis are controlled, so that the radiation generating unit 30 rotates at a specific position. The detector 40 is controlled as if moving vertically.

Referring to FIG. 2, the radiation generator 30 is controlled to rotate in the vertical direction with respect to the imaging target (S) about the reference axis (R1), and the detector 40 is controlled to rotate in the vertical direction with respect to the imaging target (S) along the reference plane (R2). It is controlled as if moving up and down from the back of (S). In one embodiment, the reference axis R1 may be understood as an axis extending in the horizontal direction, and the reference surface R2 may be understood as a surface parallel to the axis along the reference axis R1.

At position (1) in FIG. 2, the centers of the radiation generator 30 and the detector 40 are located at the same height. In a situation where the length of the detector 40 in the vertical direction is smaller than the vertical area of the object S that requires radiography, the object S is imaged while moving the detector 40. The detector 40 is controlled as if it has moved to position (2) along the reference plane (R2), and the radiation generator 30 is controlled to point toward the top of the imaging target (S) around the reference axis (R1). . Move the detector 40 and the radiation generating unit 30 so that the radiation image taken at position (1) and the radiation image taken at position (2) overlap by the overlap area (OA1) of the detector 40. Rotation is controlled.

Likewise, for imaging at position (3), the movement and rotation of the detector 40 and the radiation generator 30 are controlled, and the radiation image taken at position (1) and the radiation image taken at position (3) are The radiation image also overlaps as much as the overlap area (OA2) of the detector 40.

When imaging is completed, the radiology image at position (1), the image excluding the overlap area (OA1) among the radiology images at position (2), and the overlap area (OA2) among the radiology images at position (3). ), it is possible to obtain a radiological image for the required area of the imaging target (S) by stitching the images except for. Alternatively, the radiological image at position (1) and the radiological image at position (2) are overlapped in an overlapping area (OA1), and the radiological image at position (1) and the radiological image at position (3) are overlapped. By overlapping the overlapping area OA2 and stitching the radiological images at positions (1), (2), and (3), it is possible to obtain a radiological image for the required area of the imaging target (S).

Positions (1), (2), and (3) in FIG. 2 can be set by the control unit 50 before shooting, and positions (2), (1), and (3) can be set by the control unit 50 before shooting. Of course, shooting can be done in the order of the positions or in the reverse order.

Figure 2 illustrates stitching of three images, but depending on the length of the detector or the part of the subject (S) that needs to be captured, it is also possible to stitch two split images or four or more split images.

In addition, although FIG. 2 illustrates a state in which the imaging subject S is standing, it is also possible to apply the present invention in a state in which the imaging subject S is lying down on a bed for radiography (not shown).

Additionally, in FIG. 2, the reference axis R1 is a specific point in the xz plane, and the reference surface R2 is a straight line along the z-axis direction in the xz plane. The plane on which the surface of the detector 40 should be located can be determined based on the reference surface R2.

In addition, in Figure 2, it is illustrated that the positions of the radiation generator 30 and the detector 40 are controlled from position (1) to position (2) and from position (2) to position (3). As previously described, the radiation generator 30 and the detector are installed in the order of positions (2), (1), and (3) or in the order of positions (3), (1), and (2). The position of (40) can be controlled. Additionally, it may be possible to control the rotation of the radiation generating unit 30 and the position of the detector 40 to move only in the upward or downward direction from position (1).

According to the control method of the radiography apparatus according to the present invention, a radiographic image of the imaging target S can be acquired as if a person were scanning upward or downward with his or her eyes.

Referring to (a) of FIG. 3, the acquisition result of an ideal segmented image is illustrated. For example, when creating a final image by stitching three divided images of a subject (S), it is ideal to secure an image of uniform size without distortion in overlapping parts.

However, referring to (b) of FIG. 3, the final image generated by stitching the segmented images taken while moving the radiation generation unit and the detector sequentially from top to bottom (the heights of the radiography unit and the detector are moved the same) is It is exemplified. In this case, since the images are enlarged toward the outer edges of each divided image compared to the center, severe distortion occurs at the boundaries of the divided images. Accordingly, there is a possibility that errors may occur in image interpretation.

In contrast, the present invention allows the acquisition of a radiological image of the subject S as if scanning with the eyes, as shown in Figure 3 (c). Accordingly, in the final image generated by stitching the segmented images, the difference in magnification ratio between the center and the outside of the segmented image is not large, making it possible to obtain a more accurate final image.

In order to capture a radiation image in the manner described in FIG. 2, a method of controlling the radiation imaging device shown in FIG. 1 will be described. In the following description, it is assumed that after imaging the subject S at position (1) in FIG. 2, the radiation generator 30 and detector 40 are moved to position (2).

The radiation (R) irradiated from the radiation generating unit (30) penetrates the imaging target (S) and reaches the detector (40). At positions (1) and (2) in FIG. 2, the overlapping area (OA) in the detector 40 is related to the overlapping area (ND) in the photographing target (S). The overlap area (OA) and the overlap portion (ND) may be determined by the geometric relationship between the radiation generating unit 30, the detector 40, and the imaging target (S). In one embodiment, the user performing radiography sets the overlapping portion (ND) in the imaging target (S) through the interface unit 60, and the control unit 50 operates the detector (ND) according to the overlapping portion (ND). Determine the overlap area (OA) in 40). In another embodiment, the overlap area (OA) is first set, the radiation generator 30 and the detector 40 are rotated and moved along the reference axis (R1) and the reference surface (R2), respectively, and then the overlap area (ND) is set. ) can be inverted. In subsequent radiography, when the overlapping area (OA) is confirmed in the detector 40, stitching of the segmented images can be easily performed by deleting or overlapping the overlapping area (OA) from one segmented image and stitching it.

FIGS. 5A to 5D are diagrams illustrating a process of controlling an arm, a radiation generator, and a detector according to a control method of a radiation imaging device according to an embodiment of the present invention. FIG. 5A shows position (1) in FIG. 2, and FIG. 5D shows position (2) in FIG. 2.

Referring to FIG. 5A, the length of the detector 40 is H, the length of the overlapping area (OA) is h, and the second rotation center (C2) of the detector 40 is from the first rotation center (C1) of the arm 20. The distance to is A, and the distance from the first rotation center C1 of the arm 20 to the radiation generating unit 30 is B. A reference axis (R1) for rotation of the radiation generating unit 30 and a reference plane (R2) for movement of the detector 40 are set.

Referring to FIG. 5B, the arm 20 is rotated clockwise by an angle θ about the first rotation center C1.

Referring to FIG. 5C, the arm 20 is raised by z1 in the z-axis direction. Meanwhile, the radiation generating unit 30 is moved by b in the first direction with respect to the arm 20, so that the center of the radiation generating unit 30 coincides with the reference axis R1 in FIG. 5A. In addition, the detector 40 is moved by a amount in the first direction with respect to the arm 20 so that the position of the second rotation center (C2) is located on the reference surface (R2), and the detector 40 is positioned at the second rotation center (C2). is rotated at a predetermined angle around so that the entire detector 40 coincides with the reference surface R2. In FIG. 5A, since the reference surface R2 is shown to be set in the vertical direction, the detector 40 is rotated counterclockwise by the angle θ.

Referring to Figure 5d, the distance between the first rotation center (C1) and the detector 40 is A+a, and the distance between the first rotation center (C1) and the radiation generator 30 is B+b, so the arm ( The relationship between the initial distances A and B according to the rotation angle θ in 20) is as shown in Equation 1.

In addition, the second rotation center (C2) of the detector 40 rose by a distance of (H-h). If this is summarized in terms of A, B, and rotation angle θ, it becomes the same as Equation 2, and the rotation angle θ is expressed in Equation It is calculated by 3.

In addition, if Equation 1 is summarized for a and b, it becomes Equation 4, and accordingly, the movement distance of the radiation generator 30 and the detector 40 with respect to the arm 20 is calculated. Additionally, the rising height z1 of the arm 20 is calculated as shown in Equation 5.

Once the reference axis (R1), reference surface (R2), and overlap area (OA) are determined, the rotation angle θ of the arm 20, the movement distance of the arm 20 in the z-axis direction, and the arm of the radiation generating unit 30 The relative movement distance with respect to (20) and the relative movement distance and rotation angle of the detector 40 with respect to the arm 20 are determined. The control unit 50 controls the arm 20, the radiation generator 30, and the detector 40 according to the determined value.

The examples of FIGS. 5A to 5D are based on the assumption that the reference surface R2 is parallel to the movement of the arm 20 in the z-axis direction. However, even if the reference surface R2 is not parallel to the z-axis movement of the arm 20, the rotation and z-axis movement of the arm 20, the relative movement of the radiation generating unit 30 with respect to the arm 20, and The technical idea of the present invention can be achieved by controlling the relative movement and rotation of the detector 40 with respect to the arm 20.

Figure 6 shows an example of acquiring and stitching two radiological images as segmented images, and the same can be applied to acquiring and stitching three or more radiological images.

Radiography conditions for imaging a plurality of segmented images are set (S10). Radiation imaging conditions include the reference axis (R1) of the radiation generator 30 and the reference plane (R2) of the detector 40 for imaging a plurality of divided images, and the number of divided images according to the length of the imaging target (S). , the length of the overlapping area (OA), etc. may be included. The reference axis R1 is a reference point where the radiation generator 30 is located in space when taking a plurality of divided images, and the reference plane R2 may be a plane along which the surface of the detector 40 follows. The number of divided images can be set according to the size of the detector 40 and the length of the photographing target (S). The overlapping area (OA) can be set by receiving the overlapping part (ND) through the interface unit 60, or can be set considering the size of the detector 40 and the length of the photographing target (S).

The positions of the radiation generator 30 and the detector 40 are controlled to the first position according to the reference axis (R1) and the reference surface (R2) (S20). In one embodiment, the height of the arm 20 in the z-axis direction is controlled so that the radiation generating unit 30 is located on the reference axis R1 in the first position, and the arm 20 may be positioned in a horizontal state.

At the first position, radiation is irradiated from the radiation generator 30 and a first radiation image of the imaging target is acquired through the detector 40 (S30).

Considering the overlap area (OA) of the first radiation image and the second radiation image, the radiation generator 30 and the detector 40 are controlled to be at the second position according to the reference axis (R1) and the reference surface (R2). (S40). The radiation generator 30 is controlled as if it rotates about the reference axis (R1), and the detector 40 is controlled as if it moves along the reference plane (R2). Specifically, the arm 20 of the radiographic imaging device 1 is rotated at a predetermined angle about the second direction and moves along the third direction. The radiation generating unit 30 is moved relative to the arm 20. The detector 40 moves relative to the arm 20, while the detector 40 is rotated so that it follows the reference plane R2.

Radiation is irradiated from the radiation generator 30 at the second position, and a second radiation image of the imaging target is acquired through the detector 40 (S50).

The first radiation image and the second radiation image are stitched considering the overlapping area between the first radiation image and the second radiation image. In one embodiment, the overlapping area (OA) is excluded from one of the first radiological image and the second radiological image, or the overlapping area (OA) is overlapped with each other to stitch the first radiological image and the second radiological image. You can. Stitching for a plurality of radiation images may be performed in the control unit 50 and transmitted to the interface unit 60. Alternatively, the control unit 50 transmits the acquired first radiation image and the second radiation image to the interface unit 60, and performs stitching on the first radiation image and the second radiation image in the interface unit 60. It may be possible.

If an additional segmented image is needed for the imaging target (S), an additional segmented image following the first radiology image is acquired from a different side from the second radiology image in the same manner as S30 and S40. Alternatively, an additional segmented image following the second radiological image is acquired in the same manner as S30 and S40. For additionally acquired segmented images, other radiological images are stitched by considering the overlapping area.

The above description is merely an illustrative explanation of the technical idea of the present invention, and various modifications, changes, and substitutions can be made by those skilled in the art without departing from the essential characteristics of the present invention. will be. Accordingly, the embodiments disclosed in the present invention and the attached drawings are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments and the attached drawings. . The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

1: Radiography device

10: support

20: arm

30: radiation generation unit

40: detector

50: control unit

60: interface part

C1: first center of rotation

C2: Second rotation center

ND: Overlapping part

OA: Overlapping area

R1: reference axis

R2: reference plane

S: Shooting target

Claims

An arm that is supported to be raised and lowered on a support and can rotate about a first rotation center, a radiation generating portion provided on one side of the arm to be movable relative to the arm in a first direction, and facing the radiation generating portion. A method of controlling a radiographic imaging apparatus, comprising a detector provided on an arm, movable relative to the arm in a first direction, and rotatable about a second rotation center,

acquiring a first radiation image by controlling the arm, the radiation generator, and the detector to a first position; and

controlling the arm, the radiation generator, and the detector to a second position to obtain a second radiation image having an overlapping area that at least partially overlaps the first radiation image;

Including,

In the first position and the second position,

A method of controlling a radiographic imaging device, wherein the radiation generator rotates around a reference axis, and the detector is controlled as if it moves along the reference plane.
According to claim 1,

When controlled from the first position to the second position,

The arm rotates at a predetermined angle about the first rotation center and is raised or lowered along the support, and the radiation generator moves relative to the arm in the first direction to be moved in the first position and the second position. A method of controlling a radiography apparatus, characterized in that the radiation generating unit of is aligned with the reference axis.
According to claim 2,

The detector moves relative to the arm in the first direction and rotates to match the reference plane, so that the detector at the first position and the second position is located on the reference plane. method.
According to claim 1,

At the reference position, the reference plane is set to a plane perpendicular to the radiation irradiation direction of the radiation generating unit.
According to claim 1,

The overlapping area is calculated by receiving the length of an overlapping portion of the imaging target that overlaps the first radiological image and the second radiological image.
According to claim 1,

A control method for a radiographic imaging device, wherein the length of an overlapping portion of an imaging object that overlaps the first radiological image and the second radiological image is calculated based on the length of the overlapping area.
The method according to any one of claims 1 to 6,

A method of controlling a radiographic imaging apparatus, further comprising stitching the first radiological image and the second radiological image using the overlapping area.
A method of controlling a radiographic imaging device comprising a support, an arm supported on the support, and a radiation generator and a detector disposed on the arm to face each other,

When shooting a plurality of radiation images with overlapping areas, the radiation generator is controlled as if the radiation generator rotates about a reference axis and the detector moves along the reference plane. Control method of the imaging device.
According to claim 8,

Control of the radiation imaging device, wherein when capturing the plurality of radiation images, the radiation generating unit is aligned with the reference axis by rotating and lifting the arm and moving the radiation generating unit relative to the arm in the first direction. method.
According to claim 8,

When capturing the plurality of radiographic images, the detector is positioned on the reference plane by rotation and elevation of the arm, and relative movement and rotation of the detector in a first direction with respect to the arm. Control method.
According to claim 8,

A control method for a radiographic imaging device, characterized in that the length of the overlapped area is related to the length of the overlapped portion of the imaging target.
The method according to any one of claims 8 to 11,

A method of controlling a radiographic imaging apparatus, comprising the step of stitching the plurality of radiographic images using the overlapping area.