JP6384399B2 - X-ray fluoroscopic equipment - Google Patents

Description

  The present invention relates to an X-ray fluoroscopic apparatus that acquires an X-ray image of a subject using X-rays, and in particular, acquires a plurality of X-ray images and joins the obtained X-ray images to form a single long length. The present invention relates to an X-ray fluoroscopic apparatus that generates an image.

  In a medical field, for example, a long X-ray image (long image) for imaging a long region that is long in the body axis direction of the subject, such as the range from the neck to the knee of the subject. There is a case of taking a photo of a scale. In this case, according to the standard of the X-ray detector, it is difficult to capture a long image of a long region by one X-ray irradiation. Therefore, a plurality of X-ray images are photographed along the body axis direction of the subject, and a long image is acquired by a long photographing method in which the plurality of X-ray images are connected and reconstructed in the body axis direction. . As an example of the long photographing method, slot photographing is used (see, for example, Patent Document 1).

  Here, an X-ray fluoroscopic apparatus that performs slot imaging will be described. As shown in FIG. 16A, a conventional X-ray fluoroscopic apparatus 101 that performs slot imaging detects an X-ray and an X-ray tube 103 that irradiates a subject M taking a standing posture with X-rays. FPD105. The FPD 105 detects X-rays that are transmitted through the subject M from the X-ray tube 103, converts the detected X-rays into electrical signals, and outputs the signals as X-ray detection signals.

  The X-ray tube 103 is provided with a collimator 107. The collimator 107 limits the X-rays 103a emitted from the X-ray tube 103 to a pyramid shape under the control of the collimator control mechanism 109. The X-ray tube 103 and the FPD 105 constitute an imaging system, and are opposed to each other with the subject M interposed therebetween. Each of the imaging systems is configured to move up and down in the x direction, that is, in the vertical direction. Each movement of the imaging system is controlled by the imaging system moving mechanism 111.

  An image generation unit 113 is provided after the X-ray detector 105, and a reconstruction unit 115 is provided after the image generation unit 113. The image generation unit 113 generates a plurality of X-ray images based on the X-ray detection signal output from the FPD 105. The reconstruction unit 115 reconstructs a long image by connecting each X-ray image generated by the image generation unit 113 in the body axis direction (x direction) of the subject M.

  When slot imaging is performed using the conventional fluoroscopic imaging apparatus 101, the collimator 107 is driven according to the control of the collimator control mechanism 109. By driving the collimator 107, the X-ray irradiation field is adjusted so as to be narrowed down into a slit shape. By adjusting the X-ray irradiation field, the X-ray beam 103a emitted from the X-ray tube 103 is limited as shown in FIG. That is, a fan shape having a thickness T in the x direction from a pyramid shape (see FIG. 17 (a), above)) extending in the x direction and the y direction (left and right direction of the subject M) (see FIG. 17 (a)). a), see below). As a result, the X-ray field is limited to the central region of the FPD 105.

  After adjusting the X-ray irradiation field, an X-ray image is taken. That is, each of the X-ray tube 103 and the FPD 105 moves to an imaging start point indicated by a solid line in FIG. 17B and emits X-rays from the X-ray tube 103. The FPD 105 detects X-rays that pass through the subject M and outputs an X-ray detection signal, and the image generation unit 113 generates an X-ray image based on the X-ray detection signal. The X-ray image generated at this time is an image showing a strip-shaped region having a width T corresponding to the thickness T of the X-ray beam. A strip-shaped image generated by one X-ray irradiation is referred to as a “strip image”.

  Then, as shown in FIG. 17B, the imaging system moving mechanism 111 moves each of the X-ray tube 103 and the FPD 105 synchronously in the x direction from the imaging start point to the imaging end point indicated by a broken line. The X-ray tube 103 repeats X-ray irradiation every time it moves a distance corresponding to the thickness T of the X-ray beam in the x direction. In this way, a plurality of strip images having a width T are generated for the range from the shooting start point to the shooting end point.

  The reconstruction unit 115 reconstructs a single long image by joining the strip images generated by the image generation unit 113 in the body axis direction (x direction) of the subject M. The reconstructed long image is displayed on a monitor (not shown). The X-ray 103a irradiated when generating each strip image has a small spread in the x direction. Further, since the position of the irradiation field of the X-ray 103a is in the central region of the FPD 105, the image shown in each strip image is less distorted. Accordingly, it is possible to acquire a long image that displays an X-ray image with less distortion by slot imaging.

JP 2013-111366 A

However, the conventional example having such a configuration has the following problems.
That is, when slot imaging is performed using a conventional apparatus, the X-ray irradiation field of the strip image is limited to the central region of the FPD 105. For this reason, as shown in FIG. 17B, the imageable range R of the long image is narrower than the movable range S of the FPD 105. Therefore, it becomes difficult to include the head and foot end portions of the subject M in the imaging range of the slot imaging.

  In particular, when the subject M takes a standing posture, the movable range of the imaging system including the FPD 105 and the X-ray tube 103 is limited by the height of the floor surface W. Therefore, in order to obtain information on a state in which gravity is applied to the spine, lower limbs, and the like in the body axis direction, when slot imaging is performed on the subject M in the standing posture, the subject's foot, for example, in the vicinity of the ankle or heel. It becomes more difficult to keep the end portion of the part within the photographing range of the long image.

  When slot imaging is performed on all lower limbs, it is necessary to include the subject's ankles and the vicinity of the heel within the imaging range of the long image in order to obtain a long image with high diagnostic ability that can grasp the whole image. However, in the conventional X-ray fluoroscopic apparatus, the long-image imageable range R is narrower than the movable range S of the FPD 105. Therefore, in slot imaging using the conventional apparatus, when the vicinity of the eyelid of the subject M taking a standing posture is included in the imaging range of the long image, as shown in FIG. It is necessary to move the sample M to a relatively high position.

  However, if the subject M is an elderly person or has an injured leg, moving up to the step platform 117 to a higher position places a heavy physical burden on the subject M. In such a case, it is difficult to obtain a long image with high diagnostic ability that is included in the imaging range up to the vicinity of the eyelid. Even when the subject M can move to a higher position, the subject M is subjected to a psychological burden by standing on the step platform 117 that is more unstable than the floor W for a long time. In addition, it is difficult for the subject to keep his posture stable on the platform 117 for a long time. Therefore, there is a concern that it is difficult to acquire a high-quality long image that includes the heel portion in the imaging range.

  The present invention has been made in view of such circumstances, and provides an X-ray fluoroscopic imaging apparatus capable of suppressing slot on a subject and enabling slot imaging with a wider imaging range. Objective.

In order to achieve such an object, the present invention has the following configuration.
That is, an X-ray fluoroscopic apparatus according to the present invention includes an X-ray source that irradiates an object with X-rays, an X-ray detection unit that detects X-rays transmitted through the object on a detection surface, and shielding X-rays. A collimator that controls an X-ray irradiation field that is an X-ray irradiation field emitted from the X-ray source, collimator control means that controls opening and closing movement of the shielding part, and the X-ray source and An imaging system moving unit that moves an imaging system composed of the X-ray detection unit in the body axis direction of the subject, and the X-ray detection unit outputs while the imaging system moving unit moves each of the imaging systems. A plurality of strip image generation means for generating a plurality of strip images, which are strip-shaped X-ray images with the moving direction of the imaging system as a short direction, and a plurality of sheets generated by the strip image generation means. The strip image of the subject in the body axis direction A long image reconstruction unit that reconstructs a single long image by joining together, and the collimator control unit forms the end of the long image in the body axis direction of the subject. The X-ray irradiation field in the case of photographing the terminal image is a wider range in the body axis direction of the subject than the X-ray irradiation field in the case of photographing a strip image other than the terminal image. The imaging range of the long image is widened in the body axis direction of the subject by controlling the opening and closing movement of the shielding part.

  [Operation / Effect] According to the X-ray fluoroscopic imaging apparatus of the present invention, the collimator control unit is configured such that the X-ray irradiation field of the end image is compared with the X-ray irradiation field of the strip image other than the end image. The opening / closing movement of the shielding part is controlled so as to be in a wide range in the axial direction. The terminal image is a strip image that forms an end of a long image in the body axis direction of the subject. In this case, since the imaging range of the end image is widened, the long image becomes a wider image in the body axis direction of the subject.

  Further, in the case of having such a configuration, the shooting range of the long image is widened without changing the moving range of the imaging system. That is, it is not necessary to make a significant design change of the apparatus that changes the movable range of the imaging system. Therefore, it is possible to realize low-cost imaging of a long image having a high diagnostic ability with a wider range of the subject as a region of interest.

  Further, in the above-described invention, the collimator includes a pair of the shielding portions arranged in parallel in the body axis direction of the subject, and the collimator control means is configured to detect the X-ray irradiation field when the terminal image is captured. The opening / closing movement of one of the pair of shielding portions is controlled so as to be wider in the body axis direction of the subject compared to the X-ray irradiation field in the case of taking a strip image other than the end image. It is preferable.

  [Operation / Effect] According to the X-ray fluoroscopic apparatus according to the present invention, the collimator includes the pair of shielding portions arranged in the body axis direction of the subject. The collimator control means widens the X-ray irradiation field of the end image in the body axis direction of the subject by controlling the opening / closing movement of one of the pair of shielding portions. In this case, since one shielding part is moved so that the photographing range of the long image is widened, the X-ray irradiation field of the end image is longer than the X-ray irradiation field of the strip image other than the end image. Widen on the side closer to the end.

  On the other hand, the X-ray irradiation field of the end image does not become wide on the side far from the end of the long image. As a result, the shooting range of the end image overlaps the shooting range of the strip image other than the end image, or the distance between the shooting position of the end image and the shooting position of the strip image other than the end image is a strip image other than the end image. It is avoided that the distance between the shooting positions is different. As a result, it is possible to achieve both the reduction of the exposure dose of the subject and the simpler control of the timing of X-ray irradiation by the X-ray source.

  In the above-described invention, the collimator control means may be configured such that the X-ray irradiation field in the case where any one of the end images is taken is the X-ray irradiation field in the case where a strip image other than the end image is taken. In comparison, it is preferable to control the opening and closing movement of the shielding portion so that the range is wider in the body axis direction of the subject.

  [Operation / Effect] According to the X-ray fluoroscopic apparatus according to the present invention, the collimator control unit is configured such that either one of the end images has an X-ray irradiation field compared to an X-ray irradiation field of a strip image other than the end image. The opening / closing movement of the shielding unit is controlled so as to be in a wide range in the body axis direction of the subject. In this case, a terminal image that needs to be widened is arbitrarily selected, and the X-ray irradiation field of the selected terminal image is widened. On the other hand, the X-ray irradiation field is narrowed as usual for the end image that does not require the imaging range to be expanded. Therefore, it is possible to capture a long image with a high diagnostic ability, in which a longer image capturing range is a region of interest, and to further reduce the exposure dose of the subject.

  Further, in the above-described invention, the imaging apparatus further includes imaging range expansion instruction means for inputting an instruction to widen the imaging range of the long image in the body axis direction of the subject, and the collimator control means includes the imaging range. When the instruction is input to the extension instruction means, the X-ray irradiation field when the terminal image is captured is compared with the X-ray irradiation field when the strip image other than the terminal image is captured. It is preferable to control the opening / closing movement of the shielding portion so as to be in a wide range in the body axis direction of the specimen.

  [Operation / Effect] The X-ray fluoroscopic apparatus according to the present invention includes an imaging range expansion instructing unit for inputting an instruction to expand the imaging range of a long image in the body axis direction of the subject. The collimator control means widens the X-ray irradiation field in the direction of the body axis of the subject when an instruction is inputted to the imaging range expansion instruction means. In such a configuration, when it is not necessary to adjust the X-ray irradiation field of the end image to widen the imaging range of the long image in the body axis direction of the subject, the X-ray irradiation field of all the strip images is the subject. It is adjusted so as to become narrower in the body axis direction. Accordingly, since each strip image is an image with less distortion, the long image is a high-quality X-ray image with less distortion. That is, when it is not necessary to widen the imaging range of the long image in the body axis direction of the subject, the situation in which the distortion of the long image increases due to unnecessarily widening the X-ray irradiation field of the terminal image. Can be avoided.

  In the above-described invention, the collimator control means may be configured such that the X-ray irradiation field when the imaging position of the imaging system is at the end of the range of the imaging position, and the imaging position is other than the end of the range of the imaging position. It is preferable to control the opening / closing movement of the shielding unit so that it is in a wider range in the body axis direction of the subject as compared to the X-ray irradiation field in the case of.

  [Operation / Effect] According to the fluoroscopic imaging apparatus of the present invention, when the imaging position of the imaging system is at the end of the range of the imaging position, the collimator control means sets the X-ray irradiation field in the body axis direction of the subject. Make it wide. In such a configuration, it is avoided that the X-ray irradiation field of the end image becomes wide when the imaging system is movable in the body axis direction of the subject. Therefore, when the imaging system is movable in the body axis direction of the subject, it is preferable to avoid a situation in which the distortion of the long image is increased by unnecessarily widening the X-ray irradiation field of the end image, thereby improving the quality. Can be obtained.

In order to achieve such an object, the present invention may take the following configurations.
That is, an X-ray fluoroscopic apparatus according to the present invention includes an X-ray source that irradiates a subject with X-rays, an X-ray detection unit that detects X-rays transmitted through the subject on a detection surface, and the X-ray source. And an imaging system moving unit that moves an imaging system composed of the X-ray detection unit in the body axis direction of the subject, and the X-ray detection unit moves the imaging system while the imaging system moving unit moves each of the imaging systems. A plurality of strip image generation means for generating a plurality of strip images, which are strip-shaped X-ray images with the moving direction of the imaging system as a short direction, using the detection signal to be output, and a plurality of pieces generated by the strip image generation means Long image reconstruction means for reconstructing a single long image by joining the strip images in the body axis direction of the subject, and the imaging position of the imaging system is the end of the range of the imaging position The focal position of the X-rays emitted from the X-ray source. The irradiation angle displacing means for displacing the X-ray irradiation angle in the body axis direction of the subject in a state where the X-ray irradiation angle is displaced while the irradiation angle displacing means displaces the X-ray irradiation angle. The means is characterized in that the strip image is sequentially photographed to widen the photographing range of the long image in the body axis direction of the subject.

  [Operation / Effect] According to the X-ray fluoroscopic apparatus of the present invention, the irradiation angle displacing means is the focal point of X-rays irradiated from the X-ray source when the imaging position of the imaging system is the end of the range of the imaging position. While maintaining the position, the X-ray irradiation angle is displaced in the body axis direction of the subject. The strip image generating unit sequentially captures strip images while the irradiation angle displacing unit displaces the X-ray irradiation angle, thereby widening the imaging range of the long image in the body axis direction of the subject.

  In the case of such a configuration, by sequentially taking strip images while displacing the X-ray irradiation angle, a strip image that reflects a range that is not captured by a conventional long image in the body axis direction of the subject is newly provided. Generated. For this reason, the shooting range of the long image is widened without changing the moving range of the imaging system. That is, it is not necessary to make a significant design change of the apparatus that changes the movable range of the imaging system. Therefore, it is possible to realize low-cost imaging of a long image having a high diagnostic ability with a wider range of the subject as a region of interest.

  In the above-described invention, the irradiation angle displacing means sets the X-ray irradiation angle of the subject when the imaging position of the imaging system is located at one predetermined end of the end of the range of the imaging position. It is preferable to displace in the body axis direction.

  [Operation / Effect] According to the fluoroscopic imaging apparatus of the present invention, when the imaging position of the imaging system is located at a predetermined one of the ends of the range of the imaging position, the irradiation angle displacement means The irradiation angle is displaced in the body axis direction of the subject. In this case, the end that needs to widen the imaging range is arbitrarily selected, and when the selected end is the imaging position, the X-ray irradiation angle is displaced and new strip images are sequentially captured. On the other hand, since the X-ray irradiation angle is not displaced at the unselected end, it is possible to avoid unnecessary irradiation of X-rays over a wide range. Therefore, it is possible to capture a long image with a high diagnostic ability, in which a longer image capturing range is a region of interest, and to further reduce the exposure dose of the subject.

  Further, in the above-described invention, a shielding unit that shields X-rays is provided, and a collimator that controls an X-ray irradiation field that is an X-ray irradiation field irradiated from the X-ray source, and an open / close movement of the shielding unit are controlled. Collimator control means, and the irradiation angle displacement means is the collimator control means, and the X-ray irradiation angle is changed by moving the shield in the body axis direction of the subject. It is preferable to displace in the axial direction.

  [Operation / Effect] According to the X-ray fluoroscopic apparatus of the present invention, the irradiation angle displacement means is a collimator control means for moving the shielding portion in the body axis direction of the subject, and the collimator control means applies the shielding portion to the subject. By moving in the body axis direction, the X-ray irradiation angle is displaced in the body axis direction of the subject. Since the displacement of the X-ray irradiation angle is controlled by the movement of the shielding part, the photographing range of the long image can be widened without changing the moving range of the imaging system.

  Further, the collimator is often mounted on an X-ray fluoroscopic apparatus for the purpose of realizing a specific application. Therefore, by realizing the displacement of the X-ray irradiation angle by controlling the shielding part, it is possible to achieve the effect of the present invention without providing a new configuration in the X-ray fluoroscopic apparatus having the conventional configuration. That is, it is possible to realize an X-ray fluoroscopic imaging apparatus that can capture a long image with high diagnostic ability, with a wider range of the subject as a region of interest, at a lower cost.

  Further, in the above-described invention, the X-ray source rotation means for rotating the X-ray source around an axis in the left-right axis direction of the subject is provided, the irradiation angle displacement means is the X-ray source rotation means, and the X-ray source rotation means It is preferable that the irradiation angle of the X-ray is displaced in the body axis direction of the subject by rotating a radiation source around an axis in the left-right axis direction of the subject.

  [Operation / Effect] According to the fluoroscopic imaging apparatus of the present invention, the irradiation angle displacement means is an X-ray source rotation means, and the X-ray source is rotated around the axis in the left-right axis direction of the subject. The X-ray irradiation angle is displaced in the body axis direction of the subject. As the X-ray source rotates around the left and right axes of the subject, the X-ray irradiation direction is changed to the body axis direction of the subject. As a result, since the X-ray irradiation angle is displaced in the body axis direction of the subject, it is possible to widen the imaging range of the long image without changing the moving range of the imaging system.

  Further, the X-ray source rotating means is often mounted on an X-ray fluoroscopic apparatus for the purpose of realizing a specific application. Therefore, by realizing the displacement of the X-ray irradiation angle by controlling the X-ray irradiation direction, the effect of the present invention can be achieved without providing a new configuration in the X-ray fluoroscopic apparatus having the conventional configuration. . That is, it is possible to realize an X-ray fluoroscopic imaging apparatus that can capture a long image with high diagnostic ability, with a wider range of the subject as a region of interest, at a lower cost.

  According to the X-ray fluoroscopic apparatus according to the present invention, the collimator controller has a wider range of the X-ray irradiation field of the end image in the body axis direction of the subject than the X-ray irradiation field of the strip image other than the end image. The opening / closing movement of the shielding part is controlled so that The terminal image is a strip image that forms an end of a long image in the body axis direction of the subject. In this case, since the imaging range of the end image is widened, the long image becomes a wider image in the body axis direction of the subject.

  Further, in the case of having such a configuration, the shooting range of the long image is widened without changing the moving range of the imaging system. That is, it is not necessary to make a significant design change of the apparatus that changes the movable range of the imaging system. Therefore, it is possible to realize low-cost imaging of a long image having a high diagnostic ability with a wider range of the subject as a region of interest.

1 is a schematic diagram illustrating a configuration of an X-ray fluoroscopic apparatus according to Embodiment 1. FIG. (A) is the schematic which shows the whole structure of an apparatus, (b) is the schematic which shows the structure of a collimator. 1 is a functional block diagram illustrating a configuration of an X-ray fluoroscopic apparatus according to Embodiment 1. FIG. It is a flowchart explaining the process of the operation | movement in the radiation tomography apparatus which concerns on each Example. (A) is a flowchart according to the first and second embodiments, and (b) is a flowchart according to the third embodiment. It is a figure explaining the operation | movement which concerns on the X-ray fluoroscopic apparatus which concerns on Example 1. FIG. (A) is a figure explaining the imaging | photography area | region of a strip image, and the elongate image reconstructed by connecting a strip image. (B) is a figure which shows the imaging range of each strip image in a prior art example, (c) is a figure which shows the imaging range of each strip image in Example 1. FIG. It is a figure explaining the process of step S2 and step S3 which concern on Example 1. FIG. (A) is a figure explaining the imaging | photography position and imaging | photography range of the strip image P1, (b) is a figure explaining control of the collimator in step S2. It is a figure explaining the process of step S4 and step S5 which concern on Example 1. FIG. (A) is a figure explaining the control of the collimator in step S4, (b) is a figure explaining the imaging position and imaging range of the strip images P2 to P (n-1). It is a figure explaining the process of step S7 which concerns on Example 1. FIG. FIG. 6 is a diagram for explaining a photographing possible range of slot photographing according to the first embodiment. FIG. 10 is a diagram illustrating an operation of the X-ray fluoroscopic apparatus according to the second embodiment. (A) is a figure which shows control of the collimator at the time of imaging | photography of strip image P2-P (n-1), (b) is a figure which shows control of the collimator at the time of imaging | photography of strip image P1, (c). FIG. 7 is a diagram illustrating control of a collimator at the time of photographing strip images Pn, and (d) is a diagram for explaining a configuration of an X-ray fluoroscopic apparatus at the time of photographing each strip image. FIG. 6 is a diagram illustrating a strip image shooting range and a strip image shooting position in the first and second embodiments. (A) is a figure which shows the imaging range and imaging position in Example 1, (b) is a figure which shows the imaging range and imaging position in Example 2, (c) is the imaging range and imaging position in a prior art example. FIG. FIG. 10 is a diagram illustrating a configuration in which an imaging system moves an X-ray irradiation field at the upper end of an imaging position range in Embodiment 3. (A) is a figure which shows the state before a movement, (b)-(d) is a figure which shows the state which moves an X-ray irradiation field in the direction of an upper end in steps, (e) is each X-ray. It is a figure which shows the position in FPD of an irradiation field. FIG. 10 is a diagram illustrating a configuration in which an imaging system moves an X-ray irradiation field at the lower end of an imaging position range in Embodiment 3. (A) is a figure which shows the state before a movement, (b)-(d) is a figure which shows the state which moves an X-ray irradiation field in the direction of a lower end in steps, (e) is each X-ray. It is a figure which shows the position in FPD of an irradiation field. FIG. 10 is a diagram illustrating an operation of the X-ray fluoroscopic apparatus according to the third embodiment. (A) is a figure which shows operation | movement of the imaging system in imaging | photography position L1, (b) is a figure which shows operation | movement of the imaging system in imaging | photography position L2-L (n-1), (c) is imaging | photography position Ln. It is a figure which shows operation | movement of the imaging system in. It is a figure explaining the imaging range of a strip image and the imaging position of a strip image in Example 3 and a prior art example. (A) is a figure which shows the imaging range and imaging position in a prior art example, (b) is a figure which shows the imaging range and imaging position in Example 3. FIG. 10 is a diagram illustrating an operation of an X-ray fluoroscopic apparatus according to a modification example of Example 3. It is a figure which shows the structure and problem of the X-ray fluoroscope which concerns on a prior art example. (A) is the schematic explaining the structure of the X-ray fluoroscopic apparatus which concerns on a prior art example, (b) is a figure which shows the state which image | photographs the strip image of the vicinity of a ridge using a step board in the conventional apparatus. . It is a figure which shows operation | movement in the X-ray fluoroscopic apparatus which concerns on a prior art example. (A) is a figure explaining the change of the shape of the X-ray beam by adjustment of an irradiation field, (b) is a figure explaining the movement of the imaging system in the conventional slot imaging, and the imaging range of a strip image.

  Embodiment 1 of the present invention will be described below with reference to the drawings.

<Description of overall configuration>
As shown in FIG. 1A, the X-ray fluoroscopic imaging apparatus 1 according to the first embodiment includes an X-ray tube 3 and an FPD 5 that are arranged to face each other with a subject M interposed therebetween. The X-ray tube 3 is suspended and supported by a suspension support 7 and irradiates the subject M with X-rays 3b from the X-ray focal point 3a. The X-ray tube 3 is provided with a collimator 9 that limits the X-rays 3b emitted from the X-ray focal point 3a to a cone shape that is a pyramid.

  The FPD 5 is attached to a support column 11 standing vertically to the floor W of the examination room so as to be movable up and down. The FPD 5 detects the X-ray 3b irradiated to and transmitted through the subject M from the X-ray focal point 3a, converts it into an electrical signal, and outputs it as an X-ray detection signal. The X-ray tube 3 corresponds to the X-ray source in the present invention, and the FPD 5 corresponds to the X-ray detection means in the present invention.

  The base of the suspension support 7 is provided on the ceiling of the examination room, and is extendable in the x direction, which is the vertical direction. As the suspension support 7 expands and contracts, the position of the X-ray tube 3 in the x direction is changed. The suspension support body 7 is configured to be horizontally movable in the z direction (the front-rear direction of the subject M) along the rail 13 laid on the ceiling.

  As shown in FIG. 1B, the collimator 9 includes two plate-shaped shielding plates 9a arranged in the x direction. Each of the shielding plates 9a is made of a material that shields X-rays, and an example thereof is lead. In the first embodiment, each of the pair of shielding plates 9a is configured to move mirror-symmetrically in the x direction with reference to the central axis 3c of the X-ray 3b irradiated from the focal point 3a of the X-ray tube 3. And

  The spread of the X-ray 3b irradiated from the X-ray focal point 3a is limited to a pyramid shape by each of the shielding plates 9a. Then, the subject M is irradiated with X-rays 3b that have passed through the openings formed by the shielding plates 9a. That is, the position and range of the irradiation range (X-ray irradiation field) of the X-ray 3b are adjusted by adjusting the opening by opening and closing each of the shielding plates 9a.

  Each of the shielding plates 9a is not limited to a configuration that moves in a mirror image symmetry, and may be a configuration that moves independently. Moreover, you may change suitably the number of the shielding plates 9a with which the collimator 9 is provided. As an example, there may be mentioned a configuration including a pair of shielding plates 9a that move vertically in the x direction and a pair of shielding plates 9a that move horizontally in the y direction (left and right direction of the subject M) orthogonal to the x direction.

  As shown in FIG. 2, the X-ray fluoroscopic apparatus 1 includes an X-ray tube moving mechanism 15, an X-ray irradiation control unit 17, an FPD moving mechanism 19, and a collimator control unit 21. The X-ray tube moving mechanism 15 is provided on the suspension support 7, and the X-ray tube 3 moves in the x direction along the suspension support 7 according to the operation of the X-ray tube movement mechanism 15. In the first embodiment, since the subject M is in a standing posture, the X-ray tube 3 moves in the body axis direction of the subject M. Further, the X-ray tube moving mechanism 15 horizontally moves the suspension support 7 along the rail 13 in the z direction. In this case, the X-ray tube 3 supported by the suspension support 7 moves horizontally in the z direction according to the suspension support 7.

  The X-ray irradiation control unit 17 is configured to output a high voltage to the X-ray tube 3. And based on the high voltage output and control signal which X-ray irradiation control part 17 gave, the X-ray dose which X-ray tube 3 irradiates, and the timing which irradiates X-rays are controlled. The X-ray tube moving mechanism 15 corresponds to the X-ray source moving means in the present invention, and the X-ray irradiation control unit 17 corresponds to the X-ray irradiation control means in the present invention.

  The FPD moving mechanism 19 moves the FPD 17 in the x direction. That is, the X-ray tube moving mechanism 15 and the FPD moving mechanism 19 move the imaging system composed of the X-ray tube 3 and the FPD 5 synchronously in the x direction. Hereinafter, the position of the imaging system when capturing an X-ray image is referred to as an “imaging position”.

  The collimator control unit 21 controls the opening / closing movement of each shielding plate 9 a provided in the collimator 9. In other words, the collimator control unit 21 controls the position and range of the X-ray irradiation field. The collimator control unit 21 corresponds to the collimator control means in the present invention.

  The fluoroscopic imaging apparatus 1 further includes an image generation unit 23, a long image reconstruction unit 25, a monitor 27, a storage unit 29, an input unit 31, and a main control unit 33. The image generation unit 23 is provided at the subsequent stage of the FPD 5. The image generation unit 23 forms an X-ray image of the subject M based on the X-ray detection signal output from the FPD 5. The X-ray image generated by the image generation unit 23 in slot imaging is an X-ray image used for setting a shooting range of a long image in addition to a strip-shaped X-ray image (strip image) used for reconstruction of a long image. A fluoroscopic image is included.

  The long image reconstruction unit 25 is provided after the image generation unit 23, and reconstructs a long image by joining a series of generated strip images in the body axis direction (z direction) of the subject M. To do. The monitor 27 displays the reconstructed long image. The image generation unit 23 corresponds to a strip image generation unit in the present invention. The long image reconstruction unit 25 corresponds to the long image reconstruction means in the present invention.

  The storage unit 29 stores various parameters referred to for control of the X-ray fluoroscopic apparatus 1, X-ray images generated by the image generation unit 23, coordinate positions of a long image capturing range, and the like. Examples of parameters referred to for control of the X-ray fluoroscopic apparatus 1 include parameters of tube voltage and tube current of the X-ray tube 3.

  The input unit 31 inputs an operator's instruction, and examples thereof include a keyboard input type panel and a touch input type panel. The main control unit 33 includes an X-ray tube moving mechanism 15, an X-ray irradiation control unit 17, an FPD moving mechanism 19, a collimator control unit 21, an image generation unit 23, a long image reconstruction unit 25, a monitor 27, and a storage unit 29. Control each of these.

<Description of strip image>
Here, the shooting range of each strip image in slot shooting, which is a feature of the present invention, will be described. In slot imaging, a plurality of elongated rectangular X-ray images, that is, strip images, in which the x direction, which is the body axis direction of the subject M, is a short direction are acquired. These strip images are connected in the body axis direction of the subject M to reconstruct a single long image.

  In other words, each of the regions R1 to Rn of the subject M is imaged by the imaging operation of the fluoroscopic imaging apparatus (see the left diagram in FIG. 4A). Of the regions R1 to Rn, the region R1 located on the uppermost side (head side) in the body axis direction of the subject M is photographed to generate the strip image P1. Then, the photographing position of the strip image is moved downward in order, and finally the region Rn located on the lowermost side (foot side) is photographed to generate the strip image Pn. As a result of performing x-ray imaging in total n times as described above, a total of n strip images P1 to Pn are generated. Then, by joining the strip images P1 to Pn in the body axis direction (x direction) of the subject M, the long image Q for the long region W that is the region of interest is reconstructed (right in FIG. 4A). (See figure).

  In the conventional slot photographing, as shown in FIG. 4B, the lengths of the strip images P1 to Pn in the short direction are all a predetermined short value T1. On the other hand, in the slot photographing according to the first embodiment, the lengths of the strip images P1 and Pn in the short direction are different from those of other strip images. That is, by expanding the X-ray irradiation angle in the body axis direction of the subject M, the X-ray irradiation field of the terminal image is made wider than the X-ray irradiation field of the strip image other than the terminal image. The terminal image means two strip images located at both ends of a series of strip images in the body axis direction of the subject, that is, strip images constituting the end of the long image.

  Specifically, as shown in FIG. 4C, the strip images constituting the end of the long image Q in the x direction are the strip image P1 and the strip image Pn. In this case, each of the strip images P2 to P (n-1) which are strip images other than the terminal image has a predetermined short value T1 in the short direction (x direction). On the other hand, the strip image P1 and the strip image Pn which are the end images are configured such that the length in the x direction is T2 longer than T1.

  As described above, in the slot imaging according to the first embodiment, in the body axis direction of the subject M, the imaging range of the strip image at the end of the imaging range of the long image is wider than the imaging ranges of the other strip images. Is set. With such a configuration, in the slot photographing according to the first embodiment, the photographing range of the long image Q is wider than the moving range of the imaging system. In addition, it is not restricted to the structure which expands an imaging | photography range about both the strip image P1 and the strip image Pn. That is, the length in the short direction may be increased with respect to either the strip image P1 or the strip image Pn that is the terminal image.

  In the slot imaging according to the first embodiment, the X-ray fluoroscopic imaging apparatus 1 is an area R1 located on the uppermost side (head side) in the body axis direction of the subject M among the areas R1 to Rn illustrated in FIG. Is taken to generate a strip image P1. Then, the photographing position of the strip image is moved downward in order, and finally the region Rn located on the lowermost side (foot side) is photographed to generate the strip image Pn. Note that the order in which the strip images are taken may be changed as appropriate.

<Description of operation>
Next, an operation of slot imaging performed using the X-ray fluoroscopic apparatus 1 according to the first embodiment will be described. FIG. 3A is a flowchart for explaining the steps of the slot imaging operation performed using the X-ray fluoroscopic imaging apparatus 1 according to the first embodiment. In the first embodiment, a case where the shooting range is widened for both the strip image P1 and the strip image Pn will be described as an example.

Step S1 (setting of shooting range and shooting position)
When performing slot imaging, first, the imaging range of the long image is set for the subject M taking a standing posture. That is, the operator performs X-ray fluoroscopy with a relatively low irradiation X-ray dose, and determines the positions of the upper end and the lower end of the imaging range of the long image with reference to the X-ray fluoroscopic image generated by the image generation unit 23. Then, the operator operates the input unit 31 to input position information on the upper end and the lower end of the long image shooting range.

  By registering the position information of the upper and lower ends, the shooting range of the long image is set. In addition, when setting the imaging | photography range of a long image, it does not restrict to the structure which performs X-ray fluoroscopy. As another example, the subject M is irradiated with visible light from a visible light lamp provided in the X-ray tube 3, and the positions of the upper end and the lower end of the imaging range of the long image are determined with reference to the visible light irradiation field. The structure to perform is mentioned.

  Then, the operator operates the input unit 31, and the value of the length T2 in the x direction of the end images P1 and Pn and the value of the length T1 in the x direction of the strip images P2 to P (n-1) other than the end images. Enter. The shooting positions L1 to Ln of each strip image are determined based on the position of the shooting range of the long image, the value of the length T1, and the value of the length T2. By determining the shooting positions L1 to Ln, a shooting position range L having both ends of the shooting position L1 and the shooting position Ln is set. The photographing position range L means a photographing position range in the x direction.

Step S2 (adjustment of X-ray field)
After the shooting range of the long image is set, an operation for shooting the strip image P1 which is the end image is performed. The operator operates the input unit 31 to input an instruction to move each imaging system to the imaging position of the strip image P1, and inputs an instruction to control the collimator 9 to adjust the X-ray irradiation field. As shown in FIG. 5A, each of the imaging systems including the X-ray tube 3 and the FPD 5 moves to the photographing position L1 of the strip image P1 in accordance with an instruction input to the input unit 31.

  Each of the shielding plates 9a moves mirror-symmetrically in the x direction according to a signal transmitted from the collimator control unit 21. As a result, since the X-ray irradiation angle becomes wider in the body axis direction of the subject M, the X-ray 3b irradiated from the X-ray focal point 3a spreads in the y direction and has a cone beam shape having a thickness T2 in the x direction. (FIG. 9C). In addition, it is preferable to control each position of the shielding plate 9a so that cone beam X-rays 3b are irradiated on the entire surface of the FPD 5. That is, in the x direction, the length T2 of the shooting range of the strip image P1 is preferably equal to the length of the detection surface of the FPD 5. In this case, the length of T2 is about 35 cm to 45 cm as an example.

Step S3 (shooting strip image P1)
After the X-ray irradiation field is adjusted and the imaging system is moved to the imaging position L1, the operator operates the input unit 31 to input an instruction for starting the imaging of each strip image. First, the strip image P1 is captured when the strip image starts to be captured. That is, the X-ray 3b is irradiated to the subject M from the focal point 3a of the X-ray tube 3 at the imaging position L1. At this time, the X-ray irradiation conditions such as the tube voltage are set so that the X-ray imaging is performed so that the X-ray dose to be irradiated is higher than the X-ray fluoroscopy. The FPD 5 detects the X-ray 3b that passes through the subject M and outputs an X-ray detection signal. Based on the X-ray detection signal, the image generator 23 generates a strip image P1 having a length in the x direction as T2.

Step S4 (adjustment of X-ray irradiation field)
After the strip image P1 is captured, the X-ray irradiation field is adjusted again in order to capture the strip images P2 to P (n-1) which are non-terminal images. The photographing range of each of the strip images P2 to P (n-1) has a length in the lateral direction of T1. Therefore, the collimator control unit 21 outputs a control signal having the content T1 as the length of the X-ray irradiation field in the x direction to the collimator 9.

  The collimator 9 moves each of the shielding plates 9a in a mirror image symmetry in the x direction according to a signal output from the collimator control unit 21. As a result, the X-ray 3b irradiated from the X-ray focal point 3a spreads in the y direction and spreads in the y direction from the cone beam shape having the thickness T2 in the x direction (FIG. 5B) and thick in the x direction. It is limited to a fan beam shape having a length T1 (FIG. 6A). In addition, the length of T1 is about 4 cm-6 cm as an example.

Step S5 (shooting strip images P2 to P (n-1))
After the X-ray irradiation field is adjusted in step S4, the strip images P2 to P (n-1) are taken. As shown in FIG. 6B, the X-ray tube moving mechanism 15 and the FPD moving mechanism 19 move each of the imaging systems synchronously in the x direction according to the control signal output from the main control unit 33. That is, each imaging system moves synchronously in the x direction from the shooting position L1 to the shooting position L2 of the strip image P2. At the imaging position L2, the X-ray tube 3 emits fan beam-shaped X-rays 3b. The image generation unit 23 generates a strip image P2 based on the X-ray detection signal.

  Thereafter, each time the imaging system moves in the x direction by a distance corresponding to the width T1 of the strip image, the X-ray tube 3 emits fan beam-shaped X-rays 3b according to the control of the X-ray irradiation control unit 17. repeat. Each time the X-ray 3b is irradiated, the FPD 5 detects the X-ray 3b that passes through the subject M and outputs an X-ray detection signal. The image generation unit 23 generates each of the strip images P2 to P (n−1) having the length in the x direction as T1, based on each of the output X-ray detection signals. By photographing the strip image P (n-1) at the photographing position L (n-1) of the strip image P (n-1), the process of step S5 is completed.

Step S6 (adjustment of X-ray irradiation field)
After each of the strip images P2 to P (n-1) is generated, the X-ray irradiation field is adjusted again in order to capture the last strip image Pn. The photographing range of the strip image Pn, which is the terminal image, has a length in the short direction T2. Therefore, the collimator control unit 21 outputs a control signal having the content of T2 as the length of the X-ray irradiation field in the x direction to the collimator 9.

  The collimator 9 moves each of the shielding plates 9a in a mirror image symmetry in the x direction according to a signal output from the collimator control unit 21. As a result, the X-ray 3b irradiated from the X-ray focal point 3a spreads in the y direction and spreads in the y direction from the fan beam shape having the thickness T1 in the x direction (FIG. 6A) and thick in the x direction. It is changed to a cone beam shape having a length T2 (FIG. 5B).

Step S7 (shooting strip image Pn)
After the X-ray irradiation field is adjusted in step S6, the strip image Pn is imaged. The X-ray tube moving mechanism 15 and the FPD moving mechanism 19 move each of the imaging systems synchronously in the x direction according to the control signal output from the main control unit 33. That is, each of the imaging systems is synchronously moved in the x direction from the shooting position L (n−1) to the shooting position Ln of the strip image Pn. As shown in FIG. 7, the X-ray tube 3 irradiates cone beam-shaped X-rays 3b at the imaging position Ln. Based on the X-ray detection signal, the image generation unit 23 generates a strip image Pn having a length in the x direction as T2. By generating the strip image Pn, all the strip images used for the reconstruction of the long image are acquired.

Step S8 (Reconstruction of long image)
After the strip image Pn is shot, the long image is reconstructed. That is, the long image reconstruction unit 25 reconstructs a single long image Q by connecting the strip images P1 to Pn generated by the image generation unit 23 in the body axis direction of the subject M. The reconstructed long image Q is displayed on the monitor 27 and stored in the storage unit 29. In this manner, a single long image Q that displays an X-ray image of the long region W is acquired. With the acquisition of the long image Q, all the steps related to slot photographing are completed.

<Effects of Configuration of Example 1>
Thus, by having the structure which concerns on Example 1, the long image suitable for a diagnosis can be efficiently acquired by slot imaging | photography. Here, effects obtained based on the configuration of the embodiment will be described.

  When slot imaging is performed using a conventional apparatus, all strip images are captured with the X-ray irradiation field limited to the central region of the FPD. For this reason, as shown in FIG. 17B, the imageable range R of the long image is narrower than the movable range S of the FPD 105. Therefore, it is difficult to include the end portion of the head or foot of the subject M in the long image capturing range.

  On the other hand, the X-ray fluoroscopic imaging apparatus 1 according to the first embodiment makes the X-ray irradiation field wider in the body axis direction of the subject when generating the end image than when generating the non-end image. By having such a configuration, the imaging range of the end image is widened in the body axis direction of the subject. Therefore, as shown in FIG. 8, the imaging range R of the long image is the movable range S of the FPD 5. It will be almost the same. Accordingly, it is possible to further widen the shooting range of the long image. As a result, it is possible to acquire a long image with high diagnostic ability that can grasp an imaging target in a wider range.

  Furthermore, in the first embodiment, it is not necessary to change the movement range of the X-ray source and the X-ray detection means in order to widen the imaging range of the long image. Therefore, it is possible to further widen the shootable range R of the long image without making a significant design change that changes the movable range of the imaging system. Accordingly, an X-ray fluoroscopic apparatus that generates a long image with higher diagnostic ability can be realized at a lower cost.

  In the apparatus according to the first embodiment, the position of the shielding plate 9a of the collimator 9 is controlled in order to make the X-ray irradiation field wider. In this case, the X-ray irradiation field in a range corresponding to each strip image can be controlled by appropriately moving the position of the shielding plate 9a according to the position of the imaging system that moves synchronously. Therefore, in order to widen the shooting range of the long image, it is possible to avoid complicated control of the imaging system. As a result, a long image with high diagnostic ability can be acquired by a simpler control system.

  Furthermore, in the X-ray fluoroscopic imaging apparatus 1 according to the first embodiment, the imaging range of the long image can be widened in the x direction without increasing the moving range of the imaging system. Therefore, a long image including the vicinity of the eyelid of the subject M in the imaging range can be acquired with the subject M standing on the floor W. In this case, since the subject M has a more stable posture, the physical burden and the psychological burden received by the subject M can be reduced, and the position of the subject M can be prevented from shifting during imaging. As a result, it is possible to acquire a higher quality long image.

  Next, Embodiment 2 of the present invention will be described with reference to the drawings. The radiation tomography apparatus 1A according to the second embodiment has the same configuration as the radiation tomography apparatus 1 according to the first embodiment. However, the second embodiment and the first embodiment are different in the control of the X-ray irradiation field when taking the end image.

<Control of X-ray Irradiation Field Characteristic of Example 2>
In the X-ray fluoroscopic imaging apparatus 1 according to the first embodiment, the imaging range of the long image is widened in the x direction by widening the X-ray irradiation field of the end image on both sides in the x direction. That is, when taking the end image, the collimator control unit 21 moves each of the shielding plates 9a in the x direction in a mirror image symmetry (see FIGS. 5B and 6A).

  On the other hand, in the X-ray fluoroscopic apparatus 1A according to the second embodiment, the imaging range of the long image is widened in the x direction by expanding the X-ray irradiation field of the end image in one direction in the x direction. That is, in the second embodiment, each of the shielding plates 9a is configured to be movable independently of each other. Then, the collimator control unit 21 sets one of the pair of shielding plates 9a so that the X-ray irradiation field in the terminal image is wider in the body axis direction of the subject than the X-ray irradiation field in the strip image other than the terminal image. Move in the x direction. As a result, since the X-ray irradiation angle becomes wider in the body axis direction of the subject M, the X-ray irradiation field of the terminal image is closer to the end of the long image than the X-ray irradiation field of the non-terminal image. Become wider.

  Here, the control of the collimator in the second embodiment will be specifically described with reference to the drawings. In the second embodiment, of the pair of shielding plates 9a, the shielding plate located on the head side of the subject M is denoted by reference numeral 9aU, and the shielding plate located on the foot side of the subject M is denoted by reference numeral 9aL. It shall be indicated with

  When photographing strip images P2 to P (n-1) which are strip images (non-end images) other than the end image, collimator control in the second embodiment is common to the first embodiment. That is, the collimator control unit 21 outputs a control signal having the content of T1 as the length of the X-ray irradiation field in the x direction to the collimator 9. The collimator 9 moves each of the shielding plates 9a in the x direction according to the signal output from the collimator control unit 21. As a result, as shown in FIG. 9A, the X-ray 3b irradiated from the X-ray focal point 3a is adjusted in a fan beam shape that spreads in the y direction and has a thickness T1 in the x direction.

  When photographing the strip image P1 which is the end image on the head side of the subject M, the side near the end of the long image is the head side of the subject M. Therefore, the collimator control unit 21 moves the shielding plate 9a located on the head side in the x direction out of the pair of shielding plates 9a so that the X-ray irradiation field is widened on the head side of the subject M. That is, as shown in FIG. 9B, the shielding plate 9aU translates in the x direction toward the head of the subject M in accordance with the control signal of the collimator control unit 21. As a result, the X-ray irradiation angle becomes wider toward the head in the body axis direction of the subject M, so the X-ray irradiation field of the strip image P1 becomes wider toward the head of the subject M. The X-ray 3b irradiated from the X-ray focal point 3a is adjusted in a cone beam shape that spreads in the y direction and has a thickness T3 in the x direction.

  In addition, it is preferable that the upper end of the X-ray irradiation field of the strip image P1 (the head side end of the subject M) coincides with the upper end of the detection surface of the FPD 5. Moreover, it is preferable that the lower end of the X-ray irradiation field of the strip image P1 (the foot side end of the subject M) coincides with the lower end of the X-ray irradiation field of the strip images 2 to P (n−1). In this case, the position of the shielding plate 9aU is controlled so that the distance from the center Po of the FPD 5 to the upper end of the irradiation field of the X-ray 3b becomes equal to half the length of the detection surface of the FPD 5. The position of the shielding plate 9aL is controlled so that the distance from the center Po of the FPD 5 to the lower end of the irradiation field of the X-ray 3b is (T1) / 2.

  When the strip image Pn, which is the end image on the foot side of the subject M, is taken, the side close to the end of the long image is the foot side of the subject M. Therefore, the collimator control unit 21 moves the shielding plate 9a located on the foot side of the pair of shielding plates 9a in the x direction so that the X-ray irradiation field becomes wider on the foot side of the subject M. That is, as shown in FIG. 9C, the shielding plate 9aL translates in the x direction toward the foot side of the subject M in accordance with the control signal of the collimator control unit 21. As a result, the X-ray irradiation field of the strip image P1 is widened toward the foot side of the subject M. The X-ray 3b irradiated from the X-ray focal point 3a is adjusted in a cone beam shape that spreads in the y direction and has a thickness T3 in the x direction.

  Note that the lower end of the X-ray irradiation field of the strip image Pn preferably coincides with the lower end of the detection surface of the FPD 5. Moreover, it is preferable that the upper end of the X-ray irradiation field of the strip image Pn coincides with the upper end of the X-ray irradiation field of the strip images 2 to P (n−1). In this case, the position of the shielding plate 9aL is controlled so that the distance from the center Po of the FPD 5 to the lower end of the irradiation field of the X-ray 3b becomes equal to half the length of the detection surface of the FPD 5. The position of the shielding plate 9aU is controlled such that the distance from the center Po of the FPD 5 to the upper end of the irradiation field of the X-ray 3b is (T1) / 2.

  The steps of the slot imaging operation performed using the X-ray fluoroscopic apparatus 1A according to the second embodiment are the same as those in the first embodiment. That is, first, a shooting range of a long image is set (step S1). Then, as shown in FIG. 9B, the collimator 9 is controlled so that the X-ray irradiation field is widened on the head side of the subject M (step S2). By controlling the collimator, the X-ray irradiation field is adjusted so that the length in the x direction is T3 longer than T1.

  After the X-ray irradiation field is adjusted so as to be wide on the head side of the subject M, each of the imaging systems is moved to the imaging position L1 as shown by the solid line in FIG. A strip image P1 with T3 taken is taken (step S3). Thereafter, as shown in FIG. 9A, the collimator 9 is controlled so that the length in the x direction of the X-ray irradiation field becomes T1 (step S4).

  After adjusting the X-ray irradiation field, each of the imaging systems is moved synchronously in the x direction, and strip images P2 to P (n-1) are captured (step S5). That is, the X-ray tube 3 and the FPD 5 go from the imaging position L1 indicated by the solid line in FIG. 9D to the imaging position L (n-1) of the strip image P (n-1) via the position indicated by the alternate long and short dash line. Moving. Each time the imaging system moves a distance corresponding to the length T <b> 1 in the x direction, the X-ray tube 3 repeats the irradiation of the X-ray 3 b in accordance with the control of the X-ray irradiation control unit 17. The image generation unit 23 generates each of the strip images P2 to P (n−1) having the length in the x direction as T1, based on each of the output X-ray detection signals.

  After taking the strip images P2 to P (n-1), the collimator 9 is controlled so that the X-ray irradiation field is widened on the foot side of the subject M as shown in FIG. 9C (step S6). ). By controlling the collimator, the X-ray irradiation angle becomes wider in the body axis direction of the subject M, so the length of the X-ray irradiation field in the x direction is adjusted from T1 to T3. After the X-ray irradiation field is adjusted so as to be wide on the head side of the subject M, each imaging system is moved from the imaging position L (n−1) to the imaging position Ln as indicated by a solid line in FIG. The strip image Pn having the length in the x direction at T3 is photographed at the photographing position Ln (step S7). Finally, the strip images P1 to Pn are connected in the x direction to reconstruct the long image Q (step S8).

<Effects of Configuration of Example 2>
In Example 2, the X-ray irradiation field at the time of photographing the terminal image is closer to the end of the long image in the body axis direction of the subject than the X-ray irradiation field at the time of photographing the strip image other than the terminal image. The collimator is controlled so that it becomes wider. Since the X-ray irradiation field of the end image becomes wide, in the second embodiment, as in the first embodiment, the imaging range of the long image Q as a whole is wider in the x direction than the conventional example shown in FIG. (See FIG. 10B). Therefore, the terminal part of the subject M such as a heel can be included in the imaging range of the long image without changing the moving range (imaging position range) of the imaging system. As a result, a long image with higher diagnostic ability can be acquired with the subject M standing on the floor W as in the first embodiment.

  In the second embodiment, the X-ray irradiation timing can be more easily controlled while reducing the exposure dose. As shown in FIG. 10A, in the slot shooting according to the first embodiment, the shooting position of each strip image is the center of the shooting range of the strip image. For this reason, when the shooting ranges of the respective strip images are set to be adjacent to each other, the distances between the adjacent shooting positions are not all the same. As an example, the distance from the shooting position L1 to the shooting position L2 is longer than T1, which is the distance from the shooting position L2 to the shooting position L3. Therefore, when the shooting ranges of the respective strip images are set to be adjacent, the timing for irradiating X-rays is not constant.

  In Example 1, when the distance from the imaging position L1 to the imaging position L2 is set to T1 in order to avoid complication of control of X-ray irradiation, the imaging range of the strip image P1 is at least part or all of the strip image P2. And overlap. Therefore, when the imaging range of each strip image is set so that the timing of X-ray irradiation is constant, the exposure dose that the subject M receives in slot imaging increases.

  On the other hand, in the slot photographing according to the second embodiment, the photographing range of each end image is configured to expand in the direction close to the end of the long image Q in the x direction. That is, the shooting range of each end image is wider only on one side than the shooting range of strip images other than the end image. Therefore, as shown in FIG. 10B, in Example 2, even when the shooting ranges of the respective strip images are set to be adjacent, the distance between the adjacent shooting positions is T1. Therefore, it is possible to simplify the control of the timing of X-ray irradiation while reducing the exposure dose.

  Next, Embodiment 3 of the present invention will be described with reference to the drawings. The configuration of the radiation tomography apparatus 1B according to the third embodiment is the same as that of the radiation tomography apparatus according to the first and second embodiments. On the other hand, the third embodiment is different from the other embodiments with respect to the control of the X-ray irradiation field at the time of photographing the end image.

<Control of X-ray Irradiation Field Characteristic of Example 3>
In the X-ray fluoroscopic apparatus according to the first embodiment and the second embodiment, the X-ray irradiation field at the time of capturing the end image is compared with the X-ray irradiation field at the time of capturing the strip image other than the end image. By widening in the direction, the shooting range of the long image is made wider. On the other hand, in the X-ray fluoroscopic apparatus 1B according to the third embodiment, when each of the imaging systems is located at the end of the imaging position range L, the X-ray irradiation angle is displaced in the body axis direction of the subject. Widen the shooting range of long images. Hereinafter, control of the X-ray irradiation field, which is characteristic of the third embodiment, will be described by taking as an example a configuration in which the collimator 9 is controlled to change the X-ray irradiation angle. In the third embodiment, the collimator control unit 21 corresponds to the irradiation angle control means in the present invention.

  When each of the imaging systems is not located at the end of the shooting position range L, the collimator control in the third embodiment is common to the case where the strip images P2 to P (n-1) are shot in the first and second embodiments. . That is, as shown in FIG. 9A, the X-ray 3b irradiated from the X-ray focal point 3a is adjusted in a fan beam shape that spreads in the y direction and has a thickness T1 in the x direction.

  When each imaging system is located at the end of the imaging position range L (imaging position L1) on the head side of the subject, in order to widen the imaging range of the long image, X located in the central region of the FPD 5 It is necessary to move the radiation field to the head side of the subject. Accordingly, the collimator control unit 21 translates each of the shielding plates 9a in the x direction toward the head side (upward) of the subject M. As a result, since the X-ray irradiation angle is displaced in the body axis direction of the subject M, the position of the irradiation field of the X-ray 3b irradiated from the X-ray tube 3 is the central region M1a of the FPD 5 (FIG. 11A). ) To the upper region M1b (FIG. 11B).

  The collimator controller 21 further moves each of the shielding plates 9a toward the head of the subject M in the x direction. As a result, the position of the irradiation field of the X-ray 3b moves to the region M1d via the region M1c (FIG. 11C) positioned above the region M1b (FIG. 11D). The strip images P1a to P1d are generated by irradiating the X-ray 3b with the X-ray 3b when the position of the irradiation field of the X-ray 3b is in each of the regions M1a to M1d.

  Conventionally, the shooting range of the strip image shot at the shooting position L1 corresponds to the region M1a. On the other hand, in Example 3, since X-rays are sequentially irradiated while moving the X-ray irradiation field in the x direction, in addition to the strip image P1a with the region M1a as the imaging range, the strip image P1b with the regions M1b to M1d as the imaging range ~ P1d can be acquired. Therefore, the imaging range of the long image can be further widened toward the head end side of the subject M without changing each position of the imaging system.

  In Embodiment 3, strip images are captured for each of the four regions M1a to M1d at the capturing position L1, but the number of regions M1b to M1d and the length in the x direction may be appropriately changed. However, as shown in FIG. 11E, the length in the x direction of the regions M1b to M1d is preferably T1 like the region M1a, and the upper end of the region M1d coincides with the upper end of the detection surface of the FPD 5. It is preferable to set.

  When each imaging system is located at the end of the imaging position range (imaging position Ln) on the foot side of the subject, in order to widen the imaging range of the long image, the X-ray located in the central region of the FPD 5 It is necessary to move the irradiation field to the foot side of the subject. That is, as shown in FIGS. 12A to 12D, the collimator control unit 21 translates each of the shielding plates 9a in the x direction toward the foot side (downward) of the subject M. By moving the shielding plate 9a, the X-ray irradiation angle is displaced in the body axis direction of the subject M. As a result, since the irradiation field of the X-ray 3b moves to the foot side of the subject M, it is possible to obtain a strip image that more closely reflects the image of the foot end side of the subject M. Therefore, the imaging range of the long image is widened toward the distal end side of the subject without changing each position of the imaging system.

  When each imaging system is located at the end of the imaging position range (imaging position Ln) on the foot side of the subject, in order to widen the imaging range of the long image, the X-ray located in the central region of the FPD 5 It is necessary to move the irradiation field to the foot side of the subject. Therefore, the collimator control unit 21 translates each of the shielding plates 9a in the x direction toward the foot side (downward) of the subject M. As a result, the position of the irradiation field of the X-ray 3b irradiated from the X-ray tube 3 is changed from the central region Mna (FIG. 12 (a)) of the FPD 5 to the lower region Mnb (FIG. 12 (b)) and the region. It moves to the region Mnd via Mnc (FIG. 12C) (FIG. 12D).

  When the position of the irradiation field of the X-ray 3b is in each of the regions Mna to Mnd, the strip images Pna to Pnd are generated by irradiating the X-ray 3b from the X-ray tube 3. Conventionally, the shooting range of the strip image shot at the shooting position Ln corresponds to the area Mna. In the third embodiment, in addition to the strip image Pna corresponding to the area Mna, the strip image Pnb to the area Mnb to Mnd is set as the shooting range. Pnd can be acquired. Therefore, the imaging range of the long image can be further widened toward the distal end side of the subject M without changing each position of the imaging system.

<Description of Operation According to Example 3>
Next, an operation of slot imaging performed using the X-ray fluoroscopic apparatus 1B according to the third embodiment will be described. FIG. 3B is a flowchart for explaining a process of slot imaging performed using the X-ray fluoroscopic apparatus 1B according to the third embodiment. The description of the same steps as those of the other embodiments shown in FIG.

Step S1 (setting of shooting range and shooting position)
The process of step S1 in the third embodiment is the same as that in the first embodiment. That is, the positions of the upper end and the lower end of the imaging range of the long image are determined using an X-ray fluoroscopic image. Further, the operator operates the input unit 31, and the length value in the x direction of each of the strip images P1a to P1d and the strip images Pna to Pnd, and the length in the x direction of the strip images P2 to P (n-1). Enter the value of T1. As a result, the shooting positions L1 to Ln corresponding to the respective strip images are determined, and the shooting position range L is set. In Example 3, the lengths of the strip images P1a to P1d and the strip images Pna to Pnd in the x direction are all T1.

Step S2 (movement of X-ray irradiation field)
After the shooting range and shooting position are set, each of the imaging systems is moved to the shooting position L1 of the strip images P1a to P1d. Then, the collimator controller 21 translates each of the shielding plates 9a toward the head of the subject M in the x direction. As a result, since the X-ray irradiation angle is displaced in the x direction, as shown in FIG. 11D, the position of the irradiation field of the X-ray 3b is adjusted to the region M1d. The X-ray 3b is adjusted in a cone beam shape having a thickness T1 in the x direction. The movement of the X-ray irradiation field may be performed in synchronization with the movement of the imaging system to the imaging position L1. When the strip image P1a is first photographed among the strip images P1a to P1d, the process proceeds to step S3 without moving the X-ray irradiation field in step S2.

Step S3 (shooting strip images P1a to P1d)
After the X-ray irradiation field is moved to the region M1d, the operator operates the input unit 31 to input an instruction for content to start capturing each strip image. When the strip image starts to be photographed, the strip image P1d is first photographed in the X-ray irradiation field M1d. After the strip image P1d is generated, the collimator control unit 21 moves the shielding plate 9a in the x direction, and moves the irradiation field of the X-ray 3b from the region M1d to the region M1c. After the position of the X-ray irradiation field becomes the region M1c, the X-ray 3b is irradiated and the strip image P1c is photographed.

  The collimator controller 21 further controls the shielding plate 9a to move the irradiation field of the X-ray 3b from the region M1c to the region M1a via the region M1b. Then, the strip image P1b and the strip image P1a are obtained by irradiating the region M1b and the region M1a with the X-ray 3b, respectively. The strip images P1a to P1d are sequentially photographed while moving the X-ray irradiation field by controlling the collimator 9 in this way. In the third embodiment, the strip image P1d is shot first. However, the order of shooting the strip images P1a to P1d may be changed as appropriate.

Step S4 (adjustment of X-ray irradiation field)
After the strip images P1a to P1d are photographed, the X-ray irradiation field is adjusted again in order to photograph the strip images P2 to P (n-1), spread in the y direction, and have a thickness T1 in the x direction. The X-ray 3b is adjusted in a beam shape (FIG. 6A). However, in this embodiment, the strip image P1a was taken last in step S3. Therefore, the position of the X-ray irradiation field has already been adjusted to the central region M1a of the FPD 5 whose length in the x direction is T1 (FIG. 12A). That is, since the position of the X-ray irradiation field in the strip image P1a and the position of the X-ray irradiation field in the strip images P2 to P (n-1) are the same, the process proceeds to step S5 without controlling the collimator 9 in step S4. move on.

Step S5 (shooting strip images P2 to P (n-1))
After the X-ray irradiation field is adjusted in step S4, the strip images P2 to P (n-1) are taken in the same manner as in the first and second embodiments. That is, the X-ray tube moving mechanism 15 and the FPD moving mechanism 19 move each of the imaging systems synchronously in the x direction from the imaging position L1 to the imaging position Ln according to the control signal output by the main control unit 33. Each time the imaging system moves a distance corresponding to the width T1 of the strip image in the x direction, the X-ray tube 3 repeats the irradiation of the fan beam-shaped X-rays 3b in accordance with the control of the X-ray irradiation control unit 17. In this way, each of the strip images P2 to P (n-1) having the length in the x direction as T1 is generated at each of the photographing positions L2 to L (n-1).

Step S6 (movement of X-ray irradiation field)
After each of the strip images P2 to P (n-1) is generated and the imaging system is moved to the imaging position Ln, the X-ray irradiation field is moved in order to capture the strip images Pna to Pnd. When the first image to be captured among the strip images Pna to Pnd is one of the strip images Pnb to Pnd, the collimator control unit 21 controls the collimator 9 to displace the X-ray irradiation angle in the x direction, The X-ray irradiation field is appropriately moved to the regions Mnb to Mnd. However, in this embodiment, among the strip images Pna to Pnd, the strip image Mna is first photographed. That is, since the position of the X-ray irradiation field in the strip image Pna and the position of the X-ray irradiation field in the strip images P2 to P (n-1) are the same region Mna, the X-ray irradiation field is moved in step S6. Instead, the process proceeds to step S7.

Step S7 (shooting strip images Pna to Pnd)
In step S6, the position of the X-ray irradiation field is appropriately moved, and then the strip images Pna to Pnd are photographed. First, the X-ray 3b is irradiated in a state where the X-ray irradiation field is located in the region Mna which is the central region of the FPD 5, and the strip image Pna is photographed. After the strip image Pna is generated, the collimator control unit 21 moves the shielding plate 9a in the x direction to displace the X-ray irradiation angle in the x direction, and changes the X-ray 3b irradiation field from the region Mna to the region Mnb. Move. After the position of the X-ray irradiation field moves to the region Mnb, the X-ray 3b is irradiated and a strip image Pnb is taken.

  The collimator control unit 21 further controls the shielding plate 9a to displace the X-ray irradiation angle in the x direction, and moves the position of the X-ray 3b irradiation field from the region Mnb to the region Mnd via the region Mnc. Then, the strip image Pnc and the strip image Pnd are generated by irradiating the region Mnc and the region Mnd with the X-ray 3b, respectively. By controlling the collimator 9 in this way, the strip images Pna to Pnd are sequentially photographed while moving the X-ray irradiation field in the x direction. In the third embodiment, the strip image Pna is first captured. However, the order of capturing the strip images Pna to Pnd may be changed as appropriate. By generating the strip images Pna to Pnd, all the strip images used for reconstruction of the long image are acquired.

Step S8 (Reconstruction of long image)
After shooting of the strip images Pna to Pnd is completed and all the strip images are generated, the long image is reconstructed as in the first embodiment. That is, the long image reconstruction unit 25 reconstructs a single long image Q by joining the strip images generated by the image generation unit 23 in the body axis direction of the subject M. With the acquisition of the long image Q, the process related to slot shooting is completed.

  Thus, in the third embodiment, when the imaging system is located at the imaging position L1 or the imaging position Ln, which is the end of the imaging position range L, the X-ray irradiation field is moved in the x direction to Widen the shooting range. That is, the collimator 9 is controlled at the imaging position L1 to displace the X-ray irradiation angle in the x direction, and the X-ray irradiation field is sequentially moved from the region M1d to the region M1a (Steps S1 to S2, FIGS. e)). Then, X-rays 3b are irradiated in a state where the X-ray irradiation field is located in each of the regions M1a to M1d, and strip images P1a to P1d are generated (step S3, FIG. 13A).

  Next, in a state where the X-ray irradiation field is located in the region M1a that is the central region of the FPD 5, the imaging system is synchronously moved from the photographing position L1 to the photographing position Ln, and the strip images P2 to P (n-1) are sequentially photographed. (Steps S4 to S5, FIG. 13B). Finally, the collimator 9 is controlled at the imaging position Ln to displace the X-ray irradiation angle in the x direction, and the X-ray irradiation field is sequentially moved from the region Mna to the region Mnd (step S6, FIG. e)). Then, X-rays 3b are irradiated in a state where the X-ray irradiation field is located in each of the regions Mna to Mnd, and strip images Pna to Pnd are generated (step S7, FIG. 13C). A long image is generated by joining the strip images P1a to P1d, the strip images P2 to P (n-1), and the strip images Pna to Pnd in the body axis direction of the subject M (step S8).

  In the slot photographing according to the conventional example, the strip images photographed at the photographing position L1 or the photographing position Ln are strip images each having a length in the x direction T1, that is, the strip image P1 and the strip image Pn (FIG. 14 (a )). On the other hand, in the slot shooting according to the third embodiment, in addition to the strip image P1a corresponding to the strip image P1 in the conventional example, the strip images P1b to P1d are shot at the shooting position L1. Then, in addition to the strip image Pna corresponding to the strip image Pn in the conventional example, the strip images Pnb to Pnd are photographed at the photographing position Ln (FIG. 14B).

  As a result, the shooting range of the long image Q according to the third embodiment is wider in the x direction by the amount of the strip images P1b to P1d and the strip images Pnb to Pnd than the conventional example. As described above, the X-ray irradiation angle is displaced in the x direction at the photographing position L1 or the photographing position Ln which is the end of the photographing position range, so that the long range can be obtained without changing the moving range (imaging position range) of the imaging system. The image capturing range can be made wider.

  In the third embodiment, the configuration in which the X-ray irradiation field is moved in the x direction by moving each of the shielding plates 9a in the x direction has been described as an example. However, the X-ray irradiation field may be moved in the x direction. The target to be controlled is not limited to the shielding plate 9a. That is, the X-ray fluoroscopic apparatus 1B includes an X-ray rotation control unit (not shown). Then, at the imaging position L1 or the imaging position Ln, which is the end of the imaging position range L, the X-ray rotation control unit displaces the X-ray irradiation angle in the x direction by rotating the X-ray tube 3 about the y-direction axis. It may be a configuration. In such a modification of the third embodiment, the X-ray rotation control unit corresponds to the irradiation angle displacement means in the present invention.

  In this case, as shown in FIG. 15, the X-ray irradiation angle is displaced in the x direction by rotating the X-ray tube 3 around the axis in the y direction at the imaging position Ln. As a result, the irradiation field of the X-ray 3a moves in the x direction from the position indicated by the dotted line to the position indicated by the solid line. Even if it has a structure as shown in FIG. 15, since the strip images P1b to P1d and the strip images Pnb to Pnd are generated, the shooting range of the long image Q is widened in the x direction compared to the conventional example. be able to.

  The present invention is not limited to the above embodiment, and can be modified as follows.

  (1) In Example 1 and Example 2 described above, control was performed to widen the X-ray irradiation field when capturing both end images. However, when capturing one of the end images, the X-ray irradiation field was selected. The structure which makes it wide may be sufficient. In the third embodiment, the X-ray irradiation field may be moved at one of the imaging position L1 and the imaging position Ln, which is the end of the imaging position range. As an example, when the X-ray irradiation field is widened only in the strip image P1, the length of the X-ray irradiation field in the x direction is adjusted to T2 (or T3) in step S2, and the strip image P1 is photographed. Thereafter, the length of the X-ray irradiation field in the x direction is adjusted to T1, and the strip images P2 to Pn may be photographed.

  On the other hand, when the X-ray irradiation field is widened only for the strip image Pn, the length of the X-ray irradiation field in the x direction is adjusted to T1 in step S2, and the strip images P1 to P (n-1) are taken. Thereafter, the length of the X-ray irradiation field in the x direction is adjusted to T2 (or T3), and the strip image Pn may be captured. In this case, it is possible to appropriately select a part of the subject's head or foot that requires a wider imaging range. And since the strip image is image | photographed by the conventional X-ray irradiation field in the terminal of the side which is not selected, it can avoid irradiating X-rays to a wide range unnecessarily. Therefore, it is possible to take a long image with higher diagnostic ability and suitably avoid an increase in the exposure dose of the subject.

  (2) In the first embodiment and the second embodiment described above, only one X-ray irradiation field arbitrarily selected from the first strip image to be captured and the last strip image to be captured may be widened. In general slot photographing, each strip image is photographed in order from the head side to the foot side of the subject or from the foot side to the head side of the subject. That is, the strip image captured first and the strip image captured last generally correspond to an image including the end of the long image in the body axis direction of the subject, that is, a terminal image. When the strip image that widens the X-ray irradiation field is used as the strip image that is taken first or last, it becomes easier to select which of the strip images should be adjusted widely. Therefore, it is possible to widen the shooting range of the long image by simpler control.

  (3) In each of the embodiments described above, the slot imaging (imaging range expansion mode) for widening the X-ray irradiation field in the x direction and the slot imaging (normal mode) according to the conventional example according to each embodiment are appropriately switched. It may be a configuration. That is, as an example, when the range expansion switch 31a is provided in the input unit 31 as shown in FIG. 1A and the operator turns on the range expansion switch 31a, the long image Q is displayed in the shooting range expansion mode. It is good also as a structure which expands an imaging | photography range to ax direction. In this case, the range expansion switch 31a corresponds to an imaging range expansion instruction unit. The range expansion switch 31a is not limited to the configuration provided in the input unit 31. The configuration of the range expansion switch 31a is not limited to the switch, and other configurations such as buttons may be employed as appropriate.

  In such a modification, when the operator determines that the shooting range of the long image needs to be expanded, the range expansion switch 31a is appropriately turned on. When the range expansion switch 31 a is turned on, the normal mode is changed to the photographing range expansion mode, and a control signal is transmitted to the collimator control unit 21 via the main control unit 33. The collimator control unit 21 appropriately controls the collimator 9 to widen the photographing range of the end image in the x direction. As a result, the shooting range of the long image is widened in the x direction.

  When the range of the region of interest, which is the subject of shooting the long image, is narrower than the movable range of the FPD 5, the entire shooting range of the long image can be obtained by slot shooting in the normal mode without performing slot shooting in the shooting range expansion mode. Can be taken. In slot imaging in the normal mode, for all strip images, the X-ray irradiation field is located in the central region of the FPD 5 and the length in the short direction is T1. Accordingly, all the strip images acquired in the normal mode have a small spread in the x direction, so that the X-ray image reflected in each strip image has a small distortion. As described above, by appropriately switching on / off the instruction for extending the shooting range of the long image, a higher quality long image can be acquired according to the range of the region of interest.

  (4) In each of the embodiments described above, the X-ray irradiation field may be widened when the strip image capturing position is at the end of the movable range S of the FPD 5. If the position of the FPD 5 is not at the end of the movable range, the FPD may be moved further toward the end of the subject M in order to widen the long image capturing range. However, when the FPD moves to the end of the movable range, the FPD cannot be moved further to the end of the subject M. In such a case, in order to further widen the shooting range of the long image, it is necessary to widen the shooting range of the strip image in the body axis direction of the subject M.

  In such a modification, when the position of the FPD 5 is not the end of the movable range S, the FPD 5 is moved toward the end of the subject M even when the length of the strip image in the short direction is maintained at T1. By doing so, the photographing range of the long image can be widened. In this case, since the strip image has a small extent in the x direction, the distortion of the X-ray image reflected in each strip image is small. Therefore, a high-quality long image with little distortion can be acquired.

  On the other hand, when the shooting position of the strip image is at the end of the movable range S of the FPD 5, the shooting range of the long image cannot be expanded unless the shooting range of the strip image is widened in the body axis direction of the subject M. In such a case, the collimator 9 is controlled to widen the X-ray irradiation field of the strip image in the body axis direction of the subject. As a result, it is possible to further widen the shooting range of the long image without changing the movable range of the FPD 5.

  (5) In each of the above-described embodiments, X-ray tomography is performed on the subject M in a standing posture. However, the configuration according to each embodiment applies to a subject in a standing posture. Can be applied. In this case, the x direction, which is the body axis direction of the subject M and the direction in which the imaging system moves synchronously, is set to coincide with the longitudinal direction of the top plate on which the subject M is placed. The y direction is the short direction of the top plate, and the z direction is the vertical direction.

(6) In each of the embodiments described above, the base of the X-ray tube support portion 7 is provided on the ceiling of the examination room and moves horizontally in the x direction along the rail 13 laid on the ceiling. I can't. That is, the X-ray tube support portion 7 may have a configuration in which the base portion is provided on the floor surface W and horizontally moves in the x direction along the rails 13 laid on the floor surface W.
(7) In each of the embodiments described above, the strip images arranged in parallel in the x direction are set so that the shooting ranges are adjacent to each other without overlapping, but the present invention is not limited to this. That is, a configuration may be adopted in which long images are reconstructed by setting a part of the imaging range of parallel strip images to overlap and performing weighting processing on the overlapping regions.

DESCRIPTION OF SYMBOLS 1 ... X-ray fluoroscopy apparatus 3 ... X-ray tube (X-ray source)
5 ... FPD (X-ray detection means)
9 ... Collimator 9a ... Shielding plate (shielding part)
DESCRIPTION OF SYMBOLS 15 ... X-ray tube moving mechanism 17 ... X-ray irradiation control part 19 ... FPD moving mechanism 21 ... Collimator control part (collimator control means)
23 Image generating unit (strip image generating means)
25 ... long image reconstruction unit (long image reconstruction means)
27: Monitor 29 ... Storage unit 31 ... Input unit 33 ... Main control unit

Claims (9)

An X-ray source for irradiating the subject with X-rays;
X-ray detection means for detecting X-rays transmitted through the subject on the detection surface;
A collimator that includes a shielding unit that shields X-rays, and controls an X-ray irradiation field that is an X-ray irradiation field irradiated from the X-ray source;
Collimator control means for controlling the opening and closing movement of the shielding part;
An imaging system moving means for moving an imaging system comprising the X-ray source and the X-ray detection means in the body axis direction of the subject;
A strip-shaped X-ray image in which the moving direction of the imaging system is a short direction using the detection signal output by the X-ray detection means while the imaging system moving unit moves each of the imaging systems. Strip image generating means for generating a plurality of strip images,
A long image reconstructing unit that reconstructs a single long image by connecting the plurality of strip images generated by the strip image generating unit in the body axis direction of the subject;
The collimator control means is configured such that the X-ray irradiation field in the case of photographing a terminal image that is the strip image constituting the end of the long image in the body axis direction of the subject is a strip image other than the terminal image. By controlling the opening and closing movement of the shielding unit so as to be in a wider range in the body axis direction of the subject compared to the X-ray irradiation field in the case of photographing An X-ray fluoroscopic apparatus characterized by being widened in the body axis direction. The X-ray fluoroscopic apparatus according to claim 1,
The collimator includes a pair of shielding portions arranged in parallel in the body axis direction of the subject,
The collimator control means is configured such that the X-ray irradiation field when capturing the end image is wider in the body axis direction of the subject than the X-ray irradiation field when capturing a strip image other than the end image. An X-ray fluoroscopic apparatus that controls opening and closing movements of one of the pair of shielding portions so as to be in a range. The X-ray fluoroscopic apparatus according to claim 1 or 2,
The collimator control means is configured such that the X-ray irradiation field in the case of photographing any one of the end images is compared with the X-ray irradiation field in the case of photographing a strip image other than the end image. An X-ray fluoroscopic apparatus that controls the opening and closing movement of the shield so as to be in a wide range in the axial direction. The X-ray fluoroscopic apparatus according to any one of claims 1 to 3,
An imaging range expansion instructing unit for inputting an instruction to expand the imaging range of the long image in the body axis direction of the subject;
The collimator control means, when the instruction is input to the imaging range expansion instruction means, the X-ray irradiation field in the case of imaging the terminal image, the case of imaging a strip image other than the terminal image An X-ray fluoroscopic apparatus that controls the opening and closing movement of the shielding unit so as to be in a wider range in the body axis direction of the subject than the X-ray irradiation field. The X-ray fluoroscopic apparatus according to claim 1,
The collimator control means indicates the X-ray irradiation field when the imaging position of the imaging system is at the end of the range of the imaging position, and the X-ray when the imaging position is other than the end of the range of the imaging position. An X-ray fluoroscopic imaging apparatus that controls the opening and closing movement of the shielding unit so as to be in a wider range in the body axis direction of the subject as compared to an irradiation field. An X-ray source for irradiating the subject with X-rays;
X-ray detection means for detecting X-rays transmitted through the subject on the detection surface;
An imaging system moving means for moving an imaging system comprising the X-ray source and the X-ray detection means in the body axis direction of the subject;
A strip-shaped X-ray image in which the moving direction of the imaging system is a short direction using the detection signal output by the X-ray detection means while the imaging system moving unit moves each of the imaging systems. Strip image generating means for generating a plurality of strip images,
A long image reconstructing unit that reconstructs a single long image by connecting the plurality of strip images generated by the strip image generating unit in the body axis direction of the subject;
When the imaging position of the imaging system is at the end of the range of the imaging position, the X-ray irradiation angle is set in the body axis direction of the subject while maintaining the focal position of the X-ray irradiated from the X-ray source. An irradiation angle displacement means for displacing,
While the irradiation angle displacing means displaces the X-ray irradiation angle, the strip image generating means sequentially captures the strip images so that the imaging range of the long image is in the body axis direction of the subject. An X-ray fluoroscopic apparatus characterized by being widened. The X-ray fluoroscopic apparatus according to claim 6,
The irradiation angle displacing means displaces the X-ray irradiation angle in the body axis direction of the subject when the imaging position of the imaging system is located at one predetermined end of the end of the imaging position range. A fluoroscopic imaging device. The X-ray fluoroscopic apparatus according to claim 6 or 7,
A collimator that includes a shielding unit that shields X-rays, and controls an X-ray irradiation field that is an X-ray irradiation field irradiated from the X-ray source;
Collimator control means for controlling the opening and closing movement of the shielding part,
The irradiation angle displacing means is the collimator control means, and the X-ray fluoroscope is used to displace the X-ray irradiation angle in the body axis direction of the subject by moving the shielding part in the body axis direction of the subject. Shooting device. The X-ray fluoroscopic apparatus according to claim 6 or 7,
X-ray source rotation means for rotating the X-ray source around an axis in the left-right axis direction of the subject,
The irradiation angle displacing means is the X-ray source rotating means, and the X-ray irradiation angle is changed in the body axis direction of the subject by rotating the X-ray source around the left-right axis direction of the subject. X-ray fluoroscopic apparatus that displaces the lens.

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