JP4763361B2 - X-ray CT system - Google Patents

Description

  The present invention relates to an X-ray CT apparatus capable of capturing tomographic image data of a subject and performing various clinical treatments on the subject based on the tomographic image data.

  In recent years, various clinical judgments are made based on tomographic image data of a subject acquired by an X-ray CT apparatus. Here, in order to make more effective use of the tomographic image data of the X-ray CT apparatus in the field of treatment of the subject, accurate treatment is performed on the affected area of the subject immediately before or during the treatment. Is called.

  For example, (1) When performing radiotherapy on a subject, an operator formulates a treatment plan in advance and performs marking on a radiation irradiation site on the subject surface. This marking is performed on the subject on the cradle extracted from the bore after completion of imaging based on the tomographic image data of the subject imaged in the center of the bore of the X-ray CT apparatus.

  (2) Angio CT is also performed in which a catheter is inserted into the target blood vessel of the subject and tomographic image data is acquired by an X-ray CT apparatus. In Angio CT, a catheter is inserted into a subject placed in a lying state on a cradle, and the subject is moved to an imaging position in the bore for imaging (see Non-Patent Document 1, for example).

Also, (3) fluoroscopy is performed in which a puncture needle is inserted into the affected part from the outside of the taken cross section while viewing the tomographic image of the affected part of the subject. In this fluoroscopy, a sample is taken or a simple operation is performed while observing the tip of the puncture needle with a tomographic image.
Edited by Yoshinori Iwai, “Medical diagnostic imaging device”, Corona Publishing, December 20, 1988, p99-101 Written by Tsuneo Saito, “Image Processing Algorithm”, published by Modern Science Co., Ltd., March 10, 1993, p153-160

  However, according to the above background art, it is difficult to accurately determine the treatment position determined based on the captured tomographic image data on the subject. In other words, the X-ray CT apparatus has a cylindrical bore for performing imaging while placing the subject, and it is necessary to move the subject to the center of the bore during imaging. Further, when the operator performs treatment by, for example, a technique, it is possible to pull out the subject from the center of the bore. The difference between the photographing position and the treatment position causes various errors and difficulties.

  In particular, in the marking (1) described above, the deflection of the cradle on which the subject is placed differs between the imaging position and the treatment position, which causes an error. Further, in the insertion of the catheter of (2) described above, the subject is moved to the imaging position with the catheter inserted, so that an error is generated and the burden on the subject is large. Further, in the above-described fluoroscopic copy (3), the puncture needle must be inserted from outside the imaging section, which is difficult for the operator.

For these reasons, it is important how to realize an X-ray CT apparatus that can perform tomographic image data imaging and subject treatment while the subject is placed at the imaging position.
The present invention has been made to solve the above-described problems of the background art, and can perform tomographic image data imaging and subject treatment while the subject is placed at the imaging position. An object of the present invention is to provide a simple X-ray CT apparatus.

  In order to solve the above-described problems and achieve the object, an X-ray CT apparatus according to a first aspect of the invention includes a first rotating unit that includes an X-ray tube and rotates on the circumference. And a second rotating part that is mounted on an X-ray detector and rotated on the circumference, and disposed at a distance so that the rotation of the first rotating part and the rotation surface are parallel to each other. Generated by a second gantry, an imaging table disposed at an intermediate position between the first gantry and the second gantry, and placing a subject on an imaging area at the intermediate position, and the X-ray tube A data collection unit that irradiates an object in the imaging region with an X-ray beam, detects an X-ray beam transmitted through the object by the irradiation with the X-ray detector, and collects projection data of the object; Based on the projection data, tomographic image data of the subject is reconstructed. And a chromatography data processing apparatus.

  In the invention according to the first aspect, an X-ray tube is mounted on the first gantry to include a first rotating unit that rotates on the circumference, and an X-ray detector is mounted on the second gantry. Rotating on the circumference and including a second rotating part arranged at a distance so that the rotation of the first rotating part and the rotating surface are parallel to each other, and an intermediate position between the first gantry and the second gantry The subject is placed on the imaging region at the intermediate position by the imaging table disposed on the X-ray tube, the X-ray beam generated by the X-ray tube is irradiated onto the subject in the imaging region, and the subject is transmitted by this irradiation. The X-ray beam is detected by an X-ray detector, the projection data of the subject is collected by the data collection unit, and the tomographic image data of the subject is reconstructed based on the projection data by the data processing device.

  An X-ray CT apparatus according to a second aspect of the invention is the X-ray CT apparatus according to the first aspect of the invention, wherein the imaging table is along the central axis of rotation common to the first and second rotating parts. It is characterized by being arranged.

In the invention according to the second aspect, an axial cross section of the subject is imaged.
An X-ray CT apparatus according to a third aspect of the invention is the X-ray CT apparatus according to the second aspect, wherein the first and second rotating parts are placed on the center of the rotation. And a bore for penetrating the formed cradle.

In the invention of the third aspect, the subject is placed at an intermediate position through the bore.
An X-ray CT apparatus according to a fourth aspect of the invention is the X-ray CT apparatus according to the second or third aspect, wherein the X-ray CT apparatus has a length in the central axis direction of the imaging region approximately equal to the human body. It is characterized by having a size exceeding the length of the axial cross section.

In the invention according to the fourth aspect, an operator is allowed to enter the imaging area.
An X-ray CT apparatus according to a fifth aspect of the invention is characterized in that, in the invention according to the first aspect, the imaging table is disposed along the rotation surface.

In the fifth aspect of the invention, the treatment space is a space open to the subject.
The X-ray CT apparatus according to the sixth aspect of the invention is the X-ray CT apparatus according to the fourth aspect of the invention, wherein the first and second rotating sections are arranged with the common central axis of rotation as the vertical direction. It is provided.

In the invention of the sixth aspect, the vertical direction of the subject is opened.
The X-ray CT apparatus according to the seventh aspect of the invention is the X-ray CT apparatus according to the fourth aspect of the invention, wherein the first and second rotating sections are arranged with the common central axis of rotation in the horizontal direction. It is provided.

In the seventh aspect of the invention, the horizontal direction of the subject is opened.
An X-ray CT apparatus according to an eighth aspect of the present invention is the X-ray CT apparatus according to any one of the first to seventh aspects, wherein the data processing apparatus performs the image reconstruction. Means are provided.

In the invention of the eighth aspect, tomographic image data at a position deviating from the rotation plane is generated.
An X-ray CT apparatus according to a ninth aspect of the invention is the X-ray CT apparatus according to any one of the first to eighth aspects, wherein the first rotating portion further rotates on the circumference. An X-ray tube having an X-ray detector for irradiating the X-ray beam to the X-ray detector is further provided in the second rotating unit.

In the ninth aspect of the invention, two pairs of X-ray tubes and X-ray detector pairs are provided.
An X-ray CT apparatus according to a tenth aspect of the invention is the X-ray CT apparatus according to any one of the first to ninth aspects, wherein the imaging table unit is a recumbent subject, A cradle moving means for moving in the body axis direction is provided.

  An X-ray CT apparatus according to the invention of the eleventh aspect is the invention according to any one of the first to tenth aspects, wherein the first and second gantry do not change the relative position. Gantry moving means for changing the distance from the photographing table is provided.

  In the eleventh aspect of the invention, the photographic section is moved by the gantry moving means.

  As described above, according to the present invention, it is possible to perform imaging of tomographic image data and treatment by an operator at the same position in an imaging region located at a position between the first gantry and the second gantry. As a result, the error between the imaging position and the treatment position can be eliminated, accurate treatment based on the tomographic image data can be performed, and the burden on both the subject and the operator can be reduced.

The best mode for carrying out an X-ray CT apparatus according to the present invention will be described below with reference to the accompanying drawings. Note that the present invention is not limited thereby.
(Embodiment 1)
First, the overall configuration of the X-ray CT apparatus 100 according to the first embodiment will be described. FIG. 1 shows a block diagram of the X-ray CT apparatus 100. As shown in FIG. 1, the apparatus includes first and second gantry 10, 20, an operation table 4, and an operation console 6 having the same structure.

  The first and second gantry 10 and 20 have X-ray tubes 13 and 23. X-rays (not shown) radiated from the X-ray tubes 13 and 23 are formed by the collimators 12 and 22 so as to spread, for example, in a fan shape with a thickness and become a cone-shaped X-ray beam. The detectors 15 and 25 are irradiated. Here, the X-ray beam (beam) emitted from the X-ray tube 13 of the first gantry 10 is irradiated to the X-ray detector 25 of the second gantry 20, and the X-ray tube 23 of the second gantry 20. The X-ray beam emitted from the X-ray detector 15 is irradiated on the X-ray detector 15 of the first gantry 10.

  The X-ray detectors 15 and 25 have a plurality of scintillators arranged in a matrix in the spreading direction of a fan beam X-ray. The X-ray detectors 15 and 25 are wide multi-channel detectors in which a plurality of scintillators are arranged in a matrix.

  The X-ray detectors 15 and 25 form an X-ray incident surface curved in a concave shape as a whole. The X-ray detectors 15 and 25 are, for example, a combination of a scintillator made of an inorganic crystal and a photodiode (photo diode) that is a photoelectric converter.

  Data (data) collection units 16 and 26 are connected to the X-ray detectors 15 and 25. The data collection units 16 and 26 collect detection information of the individual scintillators of the X-ray detectors 15 and 25. X-ray irradiation from the X-ray tubes 13 and 23 is controlled by X-ray controllers 18 and 28. The illustration of the connection relationship between the X-ray tubes 13 and 23 and the X-ray controllers 18 and 28 and the connection relationship between the collimators 12 and 22 and the collimator controllers 17 and 27 are omitted. The collimators 12 and 22 are controlled by collimator controllers 17 and 27.

  The components from the rotation controllers 11 and 21 to the X-ray controllers 18 and 28 are mounted on the first rotating unit 14 and the second rotating unit 24 of the first and second gantry 10 and 20. As will be described later, the first rotating unit 14 and the second rotating unit 24 are juxtaposed with their rotating surfaces facing each other.

  Here, the subject or phantom is an imaging table along a central axis common to the bores 19 and 29 located at the centers of the first rotating unit 14 and the second rotating unit 24. 4 is placed. The imaging table 4 has a cradle for placing the subject or phantom and a cradle moving means, and the cradle on which the subject or phantom is placed is moved by the cradle moving means.

  The first and second rotating units 14 and 24 rotate while being controlled by the rotation controllers 11 and 21, bombard X-rays from the X-ray tubes 13 and 23, and the X-ray detectors 25 and 15 The transmitted X-ray of the phantom is detected as projection data for each view according to the rotation angle. The connection relationship between the first and second rotating units 14 and 24 and the rotation controllers 11 and 21 is not shown.

  The operation console 6 includes a data processing device 60. The data processing device 60 is configured by, for example, a computer. A control interface (interface) 62 is connected to the data processing device 60. The first gantry 10 and the second gantry 20 are connected to the control interface 62. The data processing device 60 controls the first and second gantry 10, 20 through the control interface 62.

  The data collection units 16 and 26, the X-ray controllers 18 and 28, the collimator controllers 17 and 27, and the rotation controllers 11 and 21 in the first and second gantry 10 and 20 are controlled through the control interface 62. The individual connections between these units and the control interface 62 are not shown.

  A data collection buffer 64 is also connected to the data processing device 60. The data collection buffer 64 is connected to the data collection unit 16 of the first gantry 10 and the data collection unit 26 of the second gantry 20. Data collected by the data collection units 16 and 26 is input to the data processing device 60 through the data collection buffer 64.

  The data processing device 60 performs image reconstruction using a transmission X-ray signal collected through the data collection buffer 64, that is, projection data. A storage device 66 is also connected to the data processing device 60. The storage device 66 stores projection data collected in the data collection buffer 64, reconstructed tomographic image data, a program (program) for realizing the functions of the present device, and the like.

  Further, a display device 68 and an operation device 70 are connected to the data processing device 60, respectively. The display device 68 displays the tomographic image data output from the data processing device 60 and other information. The operation device 70 is operated by an operator and inputs various instructions and information to the data processing device 60. An operator operates the apparatus interactively using the display device 68 and the operation device 70. The first and second gantry 10, 29, the imaging table 4, and the operation console 6 acquire tomographic image data by imaging a subject or a phantom.

  FIG. 2 is a diagram showing the arrangement of the first gantry 10, the second gantry 20, and the imaging table 4. The 1st gantry 10 and the 2nd gantry 20 are arrange | positioned so that a rotation surface may be opposed so that the rotation surface of the 1st rotation part 14 and the 2nd rotation part 24 may become parallel. Here, the bore 19 of the first gantry 10 and the bore 29 of the second gantry 20 form a cavity having a common central axis. Note that the space between the first gantry 10 and the second gantry 20 forms an open space along the plane of rotation existing on the xy axis plane of the coordinate axis shown in FIG. A treatment space 30 for performing various treatments on the specimen 1 is formed.

  The imaging table 4 is arranged in the x-axis direction that hits the outside of the second gantry 20 with respect to the treatment space 30. The imaging table 4 moves up and down the cradle on which the subject 1 is placed, and places the subject 1 at the center position of the bore 29 of the second gantry 20. The subject 1 arranged at the center position of the bore 29 transports the subject 1 along the common central axis of the bore 29 and the bore 19 together with the cradle, and the imaging positions are generally the first gantry 10 and the second gantry. 20 intermediate positions.

  Here, the first rotating unit 14 of the first gantry 10 and the second rotating unit 24 of the second gantry 20 are rotated in synchronization, and the X-ray tube 13 and the X-ray detection of the first rotating unit 14 are performed. The instrument 15 is opposite to the X-ray detector 25 and the X-ray tube 23 of the second rotating unit 24 and the subject 1 placed at an intermediate position between the first gantry 10 and the second gantry 20. To be located.

  The X-ray tube 13 of the first rotating unit 14 sets the X-ray beam irradiation direction as the direction in which the X-ray detector 25 of the second rotating unit 24 is positioned, and the X-ray of the second rotating unit 24. The tube 23 sets the X-ray beam irradiation direction as the direction in which the X-ray detector 15 of the first rotating unit 14 is located. The first rotating unit 14 and the second rotating unit 24 generate two sets of X-ray beams of the X-ray tube 13 and the X-ray detector 25, and the X-ray tube 23 and the X-ray detector 15. And means for performing the detection, but can also be a set.

  The data processing device 60 performs image reconstruction using the projection data acquired by the X-ray detectors 15 and 25. As this image reconstruction method, for example, projection data acquired by the X-ray detectors 15 and 25 is treated as two-dimensional cone beam projection data, and three-dimensional tomographic image data of the subject 1 is generated. A three-dimensional image reconstruction method is used (see, for example, Non-Patent Document 2).

  FIG. 3 shows the irradiation direction of the X-ray beam irradiated from the X-ray tube 13 and the X-ray detector 25 for detecting this X-ray beam when image reconstruction is performed using this three-dimensional image reconstruction method. FIG. 6 illustrates a reconfiguration plane in which position and image reconstruction is performed. The same applies when the X-ray tube 23 is used instead of the X-ray tube 13 and the X-ray detector 15 is used instead of the X-ray detector 25.

  In FIG. 3, the X-ray tube 13 positioned vertically above and below the rotation surface of the first rotating unit 14 and the X-ray detector 25 positioned vertically below and above the corresponding second rotating unit 24 are respectively shown. It is shown in the figure. For example, when the X-ray tube 13 is positioned vertically above the rotating surface of the first rotating unit 14, the X-ray detector 25 is positioned vertically below the rotating surface of the second rotating unit 24. Then, the X-ray beam irradiated from the X-ray tube 13 passes through the imaging region where the subject 1 is placed, and is detected by the X-ray detector 25 on the rotating surface of the second rotating unit 24 facing the X-ray tube 13. . The same applies to the case where the X-ray tube 13 is positioned vertically below the rotation surface of the first rotating unit 14.

  Then, by rotating the X-ray tube 13 and the X-ray detector 25 in the rotation plane, two-dimensional cone beam projection data of the imaging region is acquired. On the other hand, the recon plane on which image reconstruction is performed forms a plane orthogonal to the z-axis that coincides with the patient's body axis direction at an intermediate position between the first rotating unit 14 and the second rotating unit 25. Here, the surface forming the recon plane does not coincide with the rotation surfaces of the X-ray tube 13 and the X-ray detector 25. On the other hand, since the acquired projection data is two-dimensional cone beam projection data having a thickness, a three-dimensional image reconstruction method can be used. Can also generate tomographic image data of different reconplane planes.

  Next, the operation of the X-ray CT apparatus 100 according to the first embodiment will be described with reference to FIG. FIG. 4 is a flowchart showing the operation of the X-ray CT apparatus 100 according to the first embodiment. First, the operator places the subject 1 so that the imaging position is an intermediate position between the first gantry 10 and the second gantry 20 (step S401).

  Thereafter, the operator performs imaging of the subject 1 (step S402) and acquires projection data. Then, the data processing device 60 performs three-dimensional image reconstruction using the projection data, generates tomographic image data in the vicinity of the intermediate position between the first gantry 10 and the second gantry 20, and displays the tomographic image data on the display device. 68 (step S403).

  Thereafter, the operator interprets the displayed tomographic image data and performs treatment on the subject 1 in the treatment space 30 between the first gantry 10 and the second gantry 20 (step S404). When this treatment is, for example, marking performed by radiation therapy, the operator performs marking at a position close to the subject 1 and at an accurate position without moving the subject 1 from the imaging position.

Further, when this treatment is, for example, fluoroscopy, reliable insertion is performed at a position close to the subject 1 while viewing the image of the puncture needle inserted into the subject 1.
Thereafter, the operator determines whether to acquire tomographic image data again in consideration of the state of treatment (step S405). When acquiring tomographic image data (Yes in step S405), the operator proceeds to step S402. When photographing is performed and tomographic image data is not acquired (No at step S405), this process is terminated.

  As described above, in the first embodiment, the treatment space 30 is provided at an intermediate position between the first gantry 10 and the second gantry 20, and X is irradiated from the first gantry 10 or the second gantry 20. A line beam is detected by the second gantry 20 or the first gantry 10, and a tomographic image of the subject 1 located between the first gantry 10 and the second gantry 20 is acquired by a three-dimensional image reconstruction method. Therefore, when the operator performs treatment on the subject 1, the object 1 can be reliably detected without any error without moving the subject 1 in the treatment space 30 based on the tomographic image. The place where you want to be treated.

  In the first embodiment, the operator performs treatment on the subject 1 in the treatment space 30 at the intermediate position between the first gantry 10 and the second gantry 20. Devices such as an electrocardiograph and an angiographic device such as a C-arm can also be arranged.

In the first embodiment, the positions of the first gantry 10 and the second gantry 20 are fixed. However, the first gantry 10 or the second gantry 20 is provided with a gantry moving means, and the subject 1 It is also possible to perform photographing by moving in the z-axis direction, which is the transport direction. In this imaging, it is also possible to acquire tomographic image data based on the same principle as that of a helical scan by performing imaging while moving the gantry.
(Embodiment 2)
By the way, in the first embodiment, the bore 19 and the bore 29 positioned at the center of the first and second rotating portions 14 and 24 are arranged so that the cradle of the imaging table 4 penetrates. The rotating surfaces of the first and second rotating portions 14 and 24 may be arranged so as to be parallel to the cradle transport direction. Therefore, the second embodiment shows a case where the rotating surfaces of the first and second rotating portions 14 and 24 are arranged in parallel to the cradle transport direction.

  FIG. 5 is a diagram showing a configuration of the X-ray CT apparatus 200 according to the second embodiment. The X-ray CT apparatus 200 includes a first gantry 40, a second gantry 50, an imaging table 5, and an operation console 6 (not shown). Here, the first gantry 40, the second gantry 50, and the imaging table 5 correspond to the first gantry 10, the second gantry 20, and the imaging table 4 shown in FIG. Since the configuration is exactly the same as that shown in FIG. The operation console 6 is the same as that shown in the first embodiment.

  The first gantry 40 and the second gantry 50 are arranged with the rotation surfaces of the first and second rotating portions 14 and 24 facing each other. An imaging table 5 is disposed between the first gantry 40 and the second gantry 50 facing each other. The imaging table 5 moves the cradle on which the subject 1 is placed along the facing surface of the gantry.

  FIG. 5A is a view of the X-ray CT apparatus 200 as seen from the body axis direction in which the subject 1 is transported. The coordinate axes shown in FIG. 5 are those in which the body axis direction of the subject 1 is the z axis. Here, the first gantry 40 and the second gantry 50 shown in FIG. 5 (A) are opposed to each other so that the rotation surfaces of the first and second rotating parts 14 and 24 form a vertical plane. A treatment space 31 is formed between the first gantry 40 and the second gantry 50. In addition, the first gantry 40 and the second gantry 50 shown in FIG. Similar to the X-ray CT apparatus 100 shown in FIG. 2, the X-ray tube 13 and the X-ray detector 25, the X-ray tube 23 and the X-ray detector 15 are arranged to face each other, and A sagittal section is taken.

  FIG. 5B is a projection view of the X-ray CT apparatus 200 as seen from the gantry side surface in the x-axis direction. The second gantry 50 shown in FIG. 5B emits an X-ray beam from the X-ray tube 23 toward the subject 1, and this X-ray beam is detected by the X-ray detector 15 of the second gantry 40 facing the second gantry 50. Is detected. Note that the image reconstruction performed by the data processing device 60 of the operation console 6 is exactly the same as that shown in the first embodiment, and thus the description thereof is omitted.

  Next, the operation of the X-ray CT apparatus 200 according to the second embodiment will be described. The operator places the subject 1 in the treatment space 31 between the first gantry 40 and the second gantry 50 in a state as shown in FIG. Thereafter, the operator performs imaging and acquires and displays sagittal tomographic image data of the subject 1. On the other hand, during this time, the subject 1 remains placed in the treatment space 31 between the first gantry 40 and the second gantry 50.

  As described above, in the second embodiment, the imaging table 5 is arranged in the treatment space 31 existing between the first gantry 40 and the second gantry 50 so as to be parallel to the rotation surface of the gantry. Therefore, imaging can be performed without giving a feeling of pressure to the subject 1 while the subject 1 is placed in the treatment space 31.

  In the second embodiment, the first gantry 40 and the second gantry 50 have two sets of X-ray tubes and X-ray detector pairs, but one set of X-ray tubes and X-ray detectors. Only a detector pair can be used.

  In the second embodiment, the positions of the first gantry 40 and the second gantry 50 are fixed. However, the first gantry 40 and the second gantry 50 are provided with gantry moving means, and the subject 1 It is also possible to perform photographing by moving in the x-axis direction orthogonal to the conveyance direction. 6A and 6B show a case where the first and second gantry 40, 50 are moved in the x-axis direction while keeping the distance between the first gantry 40 and the second gantry 50 constant. FIG. At this time, the position of the sagittal section of the subject 1 moves from the position of the imaging section A shown in FIG. 6 (A) to the position of the imaging section B shown in FIG. 6 (B). In this imaging, it is also possible to acquire tomographic image data based on the same principle as that of a helical scan by performing imaging while moving the gantry.

In the second embodiment, the treatment space 31 existing between the first gantry 40 and the second gantry 50 does not give the subject 1 a feeling of pressure, but the treatment space 31 has a C-arm. An angiographic device such as the above can also be provided.
(Embodiment 3)
By the way, in the second embodiment, when the rotating surfaces of the first and second rotating portions 14 and 24 are arranged so as to be parallel to the transport direction of the cradle, the space opened above the subject 1. The first and second gantry 40, 50 are arranged so that there is a space, but the first and second gantry 40, 50 is arranged so that a space opened in the horizontal direction of the subject 1 exists. You can also Therefore, the third embodiment shows a case where the first and second gantry 40 and 50 are arranged so that a space opened in the horizontal direction of the subject 1 exists.

  FIG. 7 is a diagram showing a configuration of the X-ray CT apparatus 300 according to the third embodiment. The X-ray CT apparatus 300 includes a first gantry 80, a second gantry 90, an imaging table 7, and an operation console 6 (not shown). Here, the first gantry 80, the second gantry 90, and the imaging table 7 correspond to the first gantry 10, the second gantry 20, and the imaging table 4 shown in FIG. Since the configuration is exactly the same as that shown in FIG. The operation console 6 is the same as that shown in the first embodiment.

  The first gantry 80 and the second gantry 90 are arranged with the rotation surfaces of the first and second rotating portions 14 and 24 facing each other. An imaging table 7 is disposed between the first gantry 80 and the second gantry 90 facing each other. The imaging table 7 moves the cradle on which the subject 1 is placed along the opposing surface of the gantry.

  FIG. 7A is a view of the X-ray CT apparatus 300 as seen from the body axis direction in which the subject 1 is transported. The coordinate axes shown in FIG. 7 are those in which the body axis direction of the subject 1 is the z axis. Here, the first gantry 80 and the second gantry 90 shown in FIG. 7A are arranged to face each other so that the rotation surfaces of the first and second rotating portions 14 and 24 form a horizontal plane. A treatment space 32 is formed between the gantry 80 and the second gantry 90. The imaging table 7 is different from the imaging table 4 in the support mechanism from the floor surface so that it does not conflict with the configuration of the second gantry 90.

  Note that the first gantry 80 and the second gantry 90 shown in FIG. 7A are cross-sectional views along the xy axis. Similar to the X-ray CT apparatus 100 shown in FIG. 2, the X-ray tube 13 and the X-ray detector 25, the X-ray tube 23 and the X-ray detector 15 are arranged to face each other, and A coronal section is taken.

  FIG. 7B is a projection view of the X-ray CT apparatus 300 viewed from the gantry side surface in the x-axis direction. The first gantry 80 and the opposing second gantry 90 shown in FIG. 7B irradiate the subject 1 with the X-ray beam from the X-ray tubes 13 and 23, and the opposing X-ray detector 25, 15 detects this X-ray beam.

Note that the image reconstruction performed by the data processing device 60 of the operation console 6 is exactly the same as that shown in the first embodiment, and thus description thereof is omitted.
Next, the operation of the X-ray CT apparatus 300 according to the third embodiment will be described. The operator places the subject 1 in the treatment space 32 between the first gantry 80 and the second gantry 90 in a state as shown in FIG. Thereafter, the operator performs imaging and acquires and displays the tomographic image data of the coronal section of the subject 1. Meanwhile, during this time, the subject 1 remains placed in the treatment space 32 between the first gantry 80 and the second gantry 90.

  As described above, in the third embodiment, the imaging table 7 is placed in the treatment space 32 existing between the first gantry 80 and the second gantry 90 arranged in the vertical direction as the rotating surface of the gantry. Since they are arranged so as to be parallel to each other, imaging can be performed without giving a feeling of pressure to the subject 1 while the subject 1 is placed in the treatment space 32.

  In the third embodiment, the first gantry 80 and the second gantry 90 have two sets of X-ray tubes and X-ray detector pairs, but one set of X-ray tubes and X-ray detectors. Only a detector pair can be used.

  In the third embodiment, the positions of the first gantry 80 and the second gantry 90 are fixed. However, the first gantry 80 and the second gantry 90 are provided with gantry moving means, and the subject 1 It is also possible to perform photographing by moving in the y-axis direction orthogonal to the transport direction. In this imaging, it is also possible to perform imaging while moving the gantry and acquire tomographic image data based on the same principle as the helical scan. Further, imaging can be performed by moving the subject 1 in the z-axis direction, which is the transport direction of the subject 1.

  In the third embodiment, the rotating parts of the first and second gantry 80 and 90 are fixedly arranged so that the rotating surfaces form a horizontal plane. The rotating surfaces are arranged around the body axis of the subject 1. It can also be rotated for shooting. FIGS. 8A, 8B, and 8C show the rotation surface of the rotation unit around the body axis of the subject 1 while keeping the distance between the first gantry 80 and the second gantry 90 constant. It is a figure in the case of rotating. At this time, as shown in FIG. 8A, the X-ray CT apparatus 300 further includes a gantry support portion 85 that supports and rotates the first and second gantry 80 and 90. The position of the imaging section of the subject 1 moves from the position of the coronal section shown in FIG. 8B to the position of the sagittal section shown in FIG. 8C while adjusting the height of the imaging table 7. In this imaging, it is possible to acquire tomographic image data by performing imaging while moving the gantry.

It is a block diagram which shows the whole structure of a X-ray CT apparatus. FIG. 3 is an external view showing an arrangement of first and second gantry according to the first embodiment. 3 is an explanatory diagram illustrating image reconstruction according to Embodiment 1. FIG. 3 is a flowchart showing an operation of the X-ray CT apparatus according to the first embodiment. 6 is an external view showing the arrangement of first and second gantry according to Embodiment 2. FIG. It is explanatory drawing which shows the movement of the imaging | photography cross section by the movement of the 1st and 2nd gantry. FIG. 10 is an external view showing an arrangement of first and second gantry according to the third embodiment. It is explanatory drawing which shows rotation of the imaging | photography cross section by rotation of the 1st and 2nd gantry.

Explanation of symbols

1 Subject 4, 5, 7 Imaging table 6 Operation console 10, 40, 80 First gantry 11, 21 Rotation controller 12, 22 Collimator 13, 23 X-ray tube 14 First rotator 24 Second rotator 15 X-ray detectors 16, 26 Data collection units 17, 27 Collimator controllers 18, 28 X-ray controllers 19, 29 Bore 20, 50, 90 Second gantry 25 X-ray detectors 30, 31, 32 Treatment space 60 Data processing device 62 control interface 64 data collection buffer 66 storage device 68 display device 70 operation device 100, 200, 300 X-ray CT device

Claims (7)

A first gantry including a first rotating section that mounts an X-ray tube and rotates on the circumference;
A second gantry including a second rotating part mounted with an X-ray detector and rotated on the circumference so that the rotation of the first rotating part and the rotating surface are parallel to each other. When,
An imaging table disposed at an intermediate position between the first gantry and the second gantry, and placing a subject on an imaging area at the intermediate position;
The X-ray beam generated by the X-ray tube is irradiated to the subject in the imaging region, the X-ray beam transmitted through the subject by the irradiation is detected by the X-ray detector, and projection data of the subject A data collection unit that collects
An X-ray CT apparatus comprising: a data processing device that reconstructs tomographic image data of the subject based on the projection data ;
The imaging table is disposed along a central axis of rotation common to the first and second rotating units,
The X-ray CT apparatus, wherein each of the first and second rotating units includes a bore that penetrates a cradle on which the subject is placed at a central portion of the rotation . The X-ray CT apparatus, the length of the central axis direction of the imaging area is generally X-ray CT apparatus according to claim 1 is sized to exceed the length of the body axial section. The X-ray CT apparatus according to claim 2 , wherein the first and second rotating units are arranged with a common central axis of the rotation as a horizontal direction. The X-ray CT apparatus according to claim 1 , wherein the data processing apparatus includes a three-dimensional image reconstruction unit that performs the image reconstruction. The first rotating unit further includes an X-ray detector that rotates on the circumference, and the second rotating unit further includes an X-ray tube that irradiates the X-ray detector with an X-ray beam. The X-ray CT apparatus according to any one of claims 1 to 4 . The X-ray CT apparatus according to claim 1 , wherein the imaging table unit includes a cradle moving unit that moves a subject in a lying state in a body axis direction of the subject. The X-ray CT according to any one of claims 1 to 6 , wherein the first and second gantry includes gantry moving means for moving the first and second gantry in the body axis direction of the subject. apparatus.

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