JP2011083500A - Radiographic system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiographic system capable of obtaining a tomographic image with high accuracy even in a method for imaging a head of a human body as an subject through high demand, using an existing bucky device in supine position, lying the subject on the bucky device in supine position to stable the body axis of the subject, and obtaining a tomographic image by rotating the subject side relative to the imaging system, and capable of reducing the cost for introducing a CT imaging system because of using the existing bucky device. <P>SOLUTION: An subject holder 35, a head holder 36, a holder driving device 37, a radiation detector 32, a slit shielding plate 31, a slit plate driving device 38, and the like, are necessary for radiographic imaging, and they are composed as an attachment section 33 capable of being mounted on a bucky 34 in supine position, and a radiographic imaging system 100 includes the attachment section together with a radiation source 20, a radiographic imaging device 30, a radiation reading device 40, an image processing device 50, and the like. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a radiation imaging system that captures a radiation image typified by an X-ray image.

  Conventionally, radiation is irradiated from the outer circumference of a patient's body as a subject, the radiation transmitted through the subject is detected and converted into an image signal, and this image signal is reconstructed to obtain a three-dimensional cross-sectional image of a living body. The constructed radiation CT (computer tomography) apparatus is used in the medical field. Since radiation CT is greatly useful for diagnosing a patient's disease state and the like, introduction into a medical institution is progressing.

  In a radiation CT apparatus, a radiation source and a radiation detector are configured to be paired with each other with a subject interposed therebetween, and a large number of subjects are rotated while spirally moving around the subject around the virtual body axis of the subject. A helical scan CT method that detects the intensity of transmitted radiation at a rotational position is common. However, in the case of such an apparatus configuration, since there is a tendency to increase the size of the apparatus, a method of obtaining a tomographic image by rotating the subject side has been proposed in order to reduce the size of the apparatus (for example, Patent Documents). 1 and 2).

JP 2003-319935 A JP 2007-117247 A

  In the method of obtaining a tomographic image by rotating the subject side in the standing (sitting) state, it is difficult for the subject to stably maintain the body axis with respect to the imaging system with the rotation, so the subject moves by any means. It is difficult to obtain an accurate tomographic image. In addition, since a radiation CT apparatus has a relatively large volume, it is necessary to prepare a new room in order to install the apparatus. In a small-scale facility such as a practitioner with a small number of CT imaging, a new CT imaging apparatus Not only the cost of introduction, but also the cost of preparing a new room becomes a burden. On the other hand, the demand for computed tomography is greatest for photographing the head of a human body.

  The present invention is intended for photographing the head of a human body that is in great demand, and uses an existing supine bucky device to lay the subject on the supine bucky device so as to stabilize the body axis of the subject. Although it is a method for obtaining a tomographic image by rotating the specimen side with respect to the imaging system, it is possible to obtain a tomographic image with high accuracy, and by using an existing Bucky device, a CT imaging system can be introduced. An object of the present invention is to provide a radiation imaging system capable of reducing the introduction cost.

  The above object is achieved by the invention described below.

1. A radiation source for irradiating the subject with conical radiation;
A supine bucky capable of holding and holding the subject;
A CR detector for detecting the radiation transmitted through the subject;
A fixing means for positioning and fixing at least the head of the subject in the body axis direction of the subject on the supine position bucky, a first driving means for shifting the position of the fixing means around the body axis of the subject, and the subject Slit means having at least one rectangular opening in a direction orthogonal to the body axis direction of the specimen and shielding a part of the radiation; and second driving means for relatively moving the slit means and the CR detector; An attachment portion attachable to the supine bucky,
Each time the first driving means shifts the fixing means by a predetermined angle around the body axis of the subject, imaging is performed by irradiating radiation from the radiation source. After the irradiation, the second driving means is driven. And a control means for controlling to repeat the next photographing after the CR detector and the slit means are moved relative to each other by a predetermined amount,
The radiographic imaging system characterized in that, when the attachment unit is attached to the supine position bucky, the CR detector can take a sinogram that can reconstruct a CT image.

  2. 2. The radiation imaging system according to 1 above, wherein the control unit is provided in the attachment unit.

  3. 3. The radiation imaging system according to 1 or 2, wherein the attachment unit is detachable from the supine bucky.

  4). 4. The radiation imaging system according to claim 1, wherein the first driving unit can shift the position of the fixing unit in both forward and reverse directions around the body axis of the subject.

  5. The radiation imaging system according to any one of 1 to 4, wherein the fixing unit positions and fixes a trunk of a subject.

  6). The radiation imaging system according to any one of claims 1 to 5, further comprising a fixing auxiliary tool configured to be able to appear and retract from the supine position bucky surface, and the amount of appearance to be controlled by the control means.

  Radiation that can be introduced without preparing a new room and can perform computer tomography with high accuracy while it is a method to obtain a tomographic image by rotating the subject side for imaging of the head of a human body with high demand A photography system can be provided.

It is a conceptual diagram which shows the whole structure of the radiography system 100 in embodiment. FIG. 3 is a schematic diagram showing a state in which a subject holder and a head holder hold a trunk and a head of a subject. FIG. 3 is a schematic diagram showing a state in which a subject holder and a head holder rotate a trunk and a head of a subject. 3 is a front view of a slit shielding plate 31. FIG. It is a flowchart showing the flow of imaging | photography operation | movement. It is a schematic diagram showing how the subject holder 35 is rotated in advance so that the subject M can easily lie down. FIG. 3 is a diagram for explaining an imaging operation executed in the radiation imaging system 100. FIG. 3 is a diagram for explaining an imaging operation executed in the radiation imaging system 100. FIG. 3 is a diagram for explaining an imaging operation executed in the radiation imaging system 100. FIG. 10A is a schematic perspective view of the radiation imaging system 100 using the fixation assisting device, and FIG. 10B is a schematic view of the subject M lying on the supine position bucky 34 as seen from the body axis direction. It is. Fig.11 (a) is a schematic diagram of a fixing assistance tool, FIG.11 (b) is a schematic diagram which shows a mode that a fixing assistance tool is driven independently.

  Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to the embodiments described below. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted.

  First, the configuration of the radiation imaging system 100 will be described. FIG. 1 is a conceptual diagram illustrating an overall configuration of a radiation imaging system 100 according to an embodiment.

  In FIG. 1, a radiation imaging system 100 includes an imaging system including a radiation source 20, a supine bucky 34, an attachment unit 33, and a radiation imaging apparatus 30, and a general imaging system using a CR cassette 28 for abdominal and chest imaging. The radiation reading device 40 and the reading processing system of the image processing device 50 are also used.

  The supine position bucky 34 is configured to be able to lie down and hold the subject M, and is mounted on the examination table 29. The examination table 29 may be any shape as long as it is easy to perform imaging.

  The attachment unit 33 according to the present invention includes a subject holder 35, a head holder 36, a holder driving device 37, a CR cassette 28 that is a radiation detector incorporating a stimulable phosphor plate, a slit shielding plate 31, and a slit plate driving device. 38 and the controller 10. The attachment part 33 is configured to be attachable to the supine bucky 34 at the time of photographing. The CR cassette 28 containing the stimulable phosphor plate may be attached not to the attachment part 33 but to the holding part that originally exists in the depression bucky 34, and the controller 10 attaches to the attachment part 33. Alternatively, a configuration prepared separately may be adopted. Moreover, you may comprise another thing so that attachment to the attachment part 33 is removable.

  When CT imaging is not performed, the attachment unit 33 is stored in a predetermined location, and when CT imaging is performed, the attachment unit 33 is transported to the supine position bucky 34, and the attachment unit 33 is attached to the supine position bucky 34 and CT is performed. Take a picture.

  The head holder 36 is a fixing means for positioning and fixing the head of the subject M in the body axis direction of the subject. The subject holder 35 and the head holder 36 have a cylindrical cross section as shown in FIG. FIG. 2 is a schematic diagram showing how the subject holder 35 and the head holder 36 hold the trunk and head of the subject M.

  The holder driving device 37 functions as a driving unit (first driving unit) that allows at least the head holder 36 to be moved around the body axis of the subject.

  The subject holder 35 is configured to be rotatable about the center axis J1 of the cylinder and the head holder 36 about the center axis J2 of the cylinder so that the holder drive device 37 can rotate in both the forward and reverse directions in the direction of the arrow. Has been. The relative positional relationship between J1 and J2 is set based on the average body shape of the subject so as not to give a burden to the neck of the subject M during rotation when the head is rotated together with the trunk of the subject M. Is done.

  In order to simplify the attachment, only the head holder 36 may be rotated by the holder driving device 37.

  The subject holder 35 and the head holder 36 are continuously rotated and displaced as shown in FIG. 3 at the rotation speed instructed by the rotation instruction from the controller 10. FIG. 3 is a schematic diagram showing how the subject holder 35 and the head holder 36 rotate the trunk and head of the subject M.

  The subject holder 35 and the head holder 36 may be rotated by a dedicated driving device. The holder driving device 37 is provided with a rotation driving device such as a motor (not shown), and the subject holder 35 rotates by transmitting the rotational motion to the subject holder 35.

  It should be noted that the subject holder 35 and the head holder 36 may be rotated 360 degrees or more while holding the patient, or may be terminated with less rotation in consideration of the patient's condition such as trauma. It is desirable to acquire a sinogram of 180 degrees or more for reconstruction.

  As shown in FIG. 2, the positional relationship between the subject holder 35 and the head holder 36 is such that the head holder 36 does not apply a load to the head when the subject M is laid on the subject holder 35. It is desirable to arrange.

  Next, the radiation imaging apparatus 30 according to the present invention will be described in detail. The radiographic apparatus 30 includes a slit shielding plate 31 and a CR cassette 28 incorporating a storage phosphor plate.

  As shown in the front view of FIG. 4, the slit shielding plate 31 is provided with a plurality of linear rectangular openings, that is, slits 31a in a direction orthogonal to the body axis direction of the subject M, and a part of the radiation is provided. It is a radiation shielding plate (slit means) for shielding, and is disposed between the subject M and the stimulable phosphor plate 32.

  The slit plate driving device 38 functions as a driving means (second driving means) for moving the slit shielding plate 31 and the CR cassette 28 relative to each other. However, the CR cassette 28 containing the stimulable phosphor plate is provided with the inverted bucky 34. The slit shielding plate 31 functions to move with respect to the fixed and held CR cassette 28.

  The slit shielding plate 31 is configured to be movable horizontally (in a direction parallel to the table of the supine bucky 34) by the slit plate driving device 38 in the direction of the arrow in the drawing along the body axis direction of the subject M. The movement is instructed by the controller 10 in one direction designated in the horizontal direction, for example, from the right to the left in the figure. Although the interval width d between the slits 31a can be set as appropriate, in the present embodiment, the interval width between the slits 31a is set to 5 mm and will be described as moving to the left in the figure in the body axis direction.

  The CR cassette 28 containing the stimulable phosphor plate absorbs and accumulates the radiation R that has passed through the subject M and passed through the slit shielding plate 31, and records a sinogram of the subject M according to the intensity of the transmitted radiation. Can be generated. The CR cassette 28 incorporating the stimulable phosphor plate 32 is configured to be detachable from the radiation imaging apparatus 30 and the radiation reading apparatus 40. After recording the sinogram on the stimulable phosphor plate 32, the CR cassette 28 containing the stimulable phosphor plate is taken out from the radiation imaging apparatus 30 and inserted into the radiation reader 40 from the direction of the arrow, so that the recorded sinogram is imaged. Read as data.

  Next, the radiation reader 40 will be described in detail. The radiation reading apparatus 40 includes a reading unit 41, a signal processing unit 42, a primary storage unit 43, and a communication unit 44.

  The reading unit 41 includes an excitation light generation unit, a photoelectric conversion unit, and the like. The reading unit 41 photoelectrically converts the stimulated light generated by scanning the stimulable phosphor plate 32 built in the CR cassette 28 with the excitation light. An image signal corresponding to the light intensity of light is obtained and output to the signal processing unit 42.

  The signal processing unit 42 includes an A / D converter, converts an input analog image signal into digital image data, and performs various correction processes such as shading correction and sensitivity unevenness correction caused by the reading unit 41. And store it in the primary storage unit 43. The sinogram image data stored in the primary storage unit 43 is output to the controller 10 via the communication unit 44 and transmitted to the image processing device 50 by the controller 10.

  Note that the controller 10 and the image processing apparatus 50 are connected via the network N and can transmit and receive data to and from each other. In the present embodiment, a description will be given assuming that one controller 10 and one image processing apparatus 50 are connected via the network N. However, the controller 10 connected to the image processing apparatus 50 via the network N is described. There are no particular restrictions on the number of units and their installation locations.

  The network N is a network to which various communication lines such as a telephone line, a dedicated line, a mobile communication network, a communication satellite network, and a CATV line can be applied, and a LAN (Local Area Network) or a WAN (Wide Area Network). Various line forms such as the Internet can be applied.

  The radiation source 20, the radiation imaging device 30, the holder driving device 37, and the slit plate driving device 38 are connected to the controller 10 to control the imaging operation, and the radiation reading device 40 is connected to the controller 10 to read the reading. Controlled device. The controller 10, the radiation source 20, the radiation imaging apparatus 30, the holder driving apparatus 37, the slit plate driving apparatus 38, and the radiation reading apparatus 40 may be connected via a network or an interface such as SCSI. It may be connected by a dedicated line according to the standard.

  The controller 10 includes a CPU (Central Processing Unit) that controls each unit to be controlled, an operation panel for imaging, a display screen that displays imaging results, and the like (not shown). The amount and irradiation timing, movement of the slit shielding plate 31 in the holder driving device 37, the slit plate driving device 38, and the radiation imaging device 30 are controlled to synchronize the imaging operation.

  The controller 10 includes transmission means such as a modem and a router, and transmits sinogram image data input from the communication unit 44 of the radiation reader 40 to the image processing device 50 connected via the network N. The two-dimensional or three-dimensional tomographic image of the taken sinogram image data is reconstructed, and the reconstructed tomographic image is received from the image processing apparatus 50.

  The radiation source 20 irradiates the subject M with the radiation R in a conical shape (cone beam) at the radiation dose and the irradiation timing instructed from the controller 10 regardless of the CT imaging or the general imaging method. .

  The image processing apparatus 50 includes transmission means such as a modem and a router, reconstructs sinogram image data transmitted from the controller 10 via the network N, and further reconstructs the two-dimensional tomographic image or the two-dimensional tomographic image. Then, a three-dimensional tomographic image is formed and transmitted to the controller 10 which is a sinogram transmission source. That is, the image processing apparatus 50 has a function as image processing means for reconstructing a sinogram and forming a two-dimensional or three-dimensional tomographic image in the radiation image forming apparatus. At this time, the formed two-dimensional or three-dimensional tomographic image is diagnosed by a doctor existing on the image processing apparatus 50 side or a computer diagnostic apparatus, and the diagnosis result is processed by an input means such as an input keyboard or a communication interface. It is good also as transmitting to the apparatus 50 and transmitting with the said tomographic image.

  Next, the operation in the present embodiment will be described. FIG. 5 is a flowchart showing the flow of the photographing operation. FIG. 6 is a schematic diagram showing a state in which the subject holder 35 is rotated in advance so that the subject M can easily move and lie on the position table. 7 to 9 are diagrams for explaining an imaging operation executed in the radiation imaging system 100 according to the present invention. 7 (a), 8 (a), and 9 (a) show the situation where the subject M is imaged at the phase of each rotation angle (rotation angle of α and 2α) from the head side of the subject M. FIG. It is a figure. FIG. 7B is an initial state of zero rotation angle shown in FIG. 7A, and FIG. 8B is a predetermined angle α from the initial state of FIG. 7A as shown in FIG. 8A. 9 (b) is rotated and rotated by a predetermined angle 2α from the initial state of FIG. 7 (a) as shown in FIG. 9 (a). It is a figure which shows the sinogram of the recorded subject M. FIG.

  The slit shielding plate 31 is moved by the distance d while moving from the initial position (zero rotation angle) to the rotation angle α and while moving from the rotation angle α to 2α.

  The radiography system 100 according to the present invention is used to determine whether or not to perform imaging of the head CR-CT. A subject M having a headache or head injury visits a facility such as a hospital and head This is performed by a doctor when there is a suspicion of bleeding. In the case where the radiographic imaging system 100 is employed and imaging of the head CR-CT is performed, the doctor explains that the imaging of the head CR-CT is performed on the subject M.

  When performing imaging of the head CR-CT employing the radiation imaging system 100, the user installs the attachment unit 33 and the like on the site where imaging is performed and installs on the existing equipment such as the examination table. The controller 10 is used to prepare for photographing by setting the slit movement amount of the slit shielding plate 31 and the rotation angle of the head holder 36 to the initial setting positions, that is, the slit movement amount 0 mm and the rotation angle 0 degree (step S1).

  Next, the user performs X-ray tube position adjustment and X-ray tube irradiation field adjustment (step S2). The user installs a cassette containing the stimulable phosphor plate 32 (step S3).

  Next, as shown in FIG. 6A, the user uses the controller 10 to rotate the subject holder 35 in advance so that the subject M can easily lie down. The subject M lies on the rotated subject holder 354 as shown in FIG. The user uses the controller 10 to return the rotation angle of the subject holder 35 to 0 degrees, and aligns a predetermined head reference line of the subject M, which serves as a guide for the imaging position, with a guide (not shown). Thereafter, the user explains that the head of the subject M is fixed to the head holder 36 using, for example, a belt, and the head is fixed using the belt (step S4).

  Next, photographing is performed in step S5. While the subject M is on the subject holder 35, the user inputs an imaging instruction to the controller and starts the rotational displacement of the subject holder 35. At the same time, as shown in FIG. In the state where the rotation angle is 0 degree, the radiation source 20 emits the radiation R in a cone beam shape to perform imaging.

  When the radiation R irradiated from the radiation source 20 and transmitted through the subject M passes through the slit 31a provided in the slit shielding plate 31, scattered radiation generated by the subject M is removed by the slit shielding plate 31. At the same time, the cone beam becomes a fan beam (fan shape) and is absorbed by the stimulable phosphor plate 32 and recorded as a transmission image.

  At this time, as shown in FIG. 7A, the transmitted image recorded on the stimulable phosphor plate 32 in the first photographing is recorded at a position that coincides with the initial position of each slit number of the slit shielding plate 31. The imaging is performed while measuring the heartbeat of the subject M, and the irradiation timing of the radiation R is synchronized with the heartbeat of the subject M in order to suppress the fluctuation of the state of the subject M in the body and make the state uniform. preferable.

  Next, as shown in FIG. 8A, the slit shielding plate 31 is moved in the direction of the arrow by a predetermined amount, for example, 0.2 mm, at a position where the subject holder 35 is rotationally displaced by a predetermined angle, for example, 10 degrees around the body axis. In this state, imaging is performed by irradiating the radiation R from the radiation source 20 in the same manner as described above. At this time, the transmission image transmitted through the subject M and recorded on the stimulable phosphor plate 32 is an initial image recorded with a rotation angle of 0 degree and a slit movement amount of 0 mm as shown in FIG. Each slit number from the position is recorded on the 0.2 mm arrow side.

  In this way, at the position where the subject holder 35 is rotationally displaced every rotation angle of 10 degrees, the slit shielding plate 31 is moved in the direction of the arrow by 0.2 mm, and repeated imaging is performed. The transmission image recorded at each slit number is recorded on the arrow side every 0.2 mm. For example, as shown in FIG. 9A, when the subject holder 35 is continuously rotated and displaced from 0 to 200 degrees, and during that time, a total of 21 images are taken for each rotational displacement amount of 10 degrees, On the stimulable phosphor plate 32, a sinogram composed of 21 transmission images is recorded for each slit number as shown in FIG. 9B.

  The sinogram is image data that makes it possible to reconstruct a CT image.

  At this time, since the amount of movement of the slit is 0.2 mm for every 10 degrees of rotational displacement, the sinogram recorded by one slit 31a is recorded with a width of about 4.2 mm.

  While performing such imaging, the user pays attention to the state of the subject M (step S6) and watches whether there is any abnormality in the subject M. Special attention is required in the case of a sudden illness, and if an abnormality is recognized, the imaging is stopped (step S7).

  If there is no abnormality in the state of the subject M, the user continues the imaging and determines whether the predetermined imaging is completed (step S8). When the photographing is repeated (No in step S8), the process returns to step S5. If it is determined that shooting has been completed (Yes in step S8), the user inputs an image reconstruction instruction to the controller (step S9).

  The controller 10 causes the reading unit 41 to read a plurality of sinograms photographed at each rotation angle and recorded on the stimulable phosphor plate 32. Next, when the read sinogram image data is input from the communication unit 44, the image data is transmitted to the image processing apparatus 50 via the network N.

  The image processing device 50 analyzes the received image data and recognizes the sinogram image data for each slit 31a. Specifically, in the above-described example, the slit shielding plate 31 has a slit interval width of 5 mm, and a sinogram for each slit 31a is recorded with a width of 4.2 mm, so that image data is recorded. There is no empty area for each slit 31a. Recognizing the empty area, the image processing apparatus 50 recognizes sinogram image data for each slit 31a.

  Next, the image processing device 50 reconstructs the sinogram image data for each recognized slit 31a, forms a CT image that is a two-dimensional tomographic image for each interval width of the slit 31a in the body axis direction, and creates a three-dimensional tomographic image. If the image is required, the formed two-dimensional image is further reconstructed to form a CT image, which is a three-dimensional tomographic image, and transmitted to the controller 10.

  For example, when the interval width of the slits 31a is 5 mm, two-dimensional or three-dimensional tomographic image data is formed every 5 mm in the body axis direction.

  Note that the image processing apparatus 50 is configured such that the formed three-dimensional tomographic image data is diagnosed by a doctor existing on the image processing apparatus 50 side or a computer diagnostic apparatus, and the diagnosis result is input by a predetermined input means. 10, the diagnostic result is transmitted to the controller 10 together with the formed two-dimensional or three-dimensional tomographic image data. The controller 10 receives two-dimensional or three-dimensional tomographic image data formed from the image processing device 50 together with the diagnosis result.

  The user confirms an image based on the reconstructed two-dimensional or three-dimensional tomographic image data using a predetermined display or the like, and determines the necessity of re-imaging (step S10). If re-photographing is necessary (No in step S10), the user returns to step S5. If it is determined that re-imaging is unnecessary (Yes in step S10), the user unfixes the subject M from the subject holder 35, and then uses an apparatus such as the attachment unit 33 attached to the examination table 29 or the like. Unfixing is released (step S11).

  In the above description, every time the subject holder 35 is rotated and displaced by 10 degrees, the slit moving amount of the slit shielding plate 31 is described every 0.2 mm. However, the rotation angle and the slit for determining the imaging position are described. The amount of movement is an example, and the value can be set as appropriate. However, if the amount of movement of the slit is too small, the interval between the transmission images recorded on the stimulable phosphor plate 32 becomes small, and there is a possibility that the adjacent transmission images substantially overlap each other and reconstruction becomes difficult. 0.2 mm or more is preferable. Similarly, if the interval width of each slit 31a is too small, the interval width of each transmission image recorded on the stimulable phosphor plate 32 may be reduced and may substantially overlap, and the number of transmission images to be recorded is limited. Therefore, it is preferable to set it to 5 mm or more. In addition, if the rotation angle for each photographing is large and the resolution becomes rough, the amount of information for reconstructing a two-dimensional or three-dimensional image decreases and the resolution decreases. The rotation angle to be recorded is preferably 10 degrees or less.

  In the above description, the imaging is performed while rotating at least the subject holder 35 and the head holder 36 at the time of imaging. However, the rotation of the trunk is essential for the imaging of the head. Not required. The trunk may be in a posture such that the subject M is not burdened with the rotation of the head. Therefore, as shown in FIGS. 10 and 11, it is possible to adopt a fixing aid that is configured so as to be able to appear and retract from the surface of the lying-down bucky 34 and whose amount of appearance is controlled by the control means.

  FIG. 10A is a schematic perspective view of the radiation imaging system 100 using the fixation assisting device, and FIG. 10B is a schematic view of the subject M lying on the supine position bucky 34 as seen from the body axis direction. It is. Fig.11 (a) is a schematic diagram of a fixing assistance tool, FIG.11 (b) is a schematic diagram which shows a mode that a fixing assistance tool is driven independently.

  In FIGS. 10A and 11, reference numerals 61 and 62 denote fixing aids, and 39 denotes a fixing aid driving device. The fixing assisting device driving device 39 is controlled by the controller 10 and controls the heights of the fixing assisting devices 61 and 62 from the surface of the prone bucky 34. As shown in FIG. 10A, the fixation assisting devices 61 and 62 support the trunk of the subject M.

  As shown in FIG. 11A, the fixing auxiliary tools 61 and 62 are driven up and down in accordance with instructions from the controller 10, for example, as shown in FIG. 11B, the fixing auxiliary tools 61 are driven upward. The fixing auxiliary tool 62 can be driven downward.

  As shown in FIG. 10 (b), in accordance with the rotation of the head holder 36, one body is driven upward from the surface of the supine position bucky 34, and the other is driven downward, whereby the body of the subject M The executive can be rotated. When the subject M lies on the supine position bucky 34, the patient who is the subject M easily lies on the supine position bucky by immersing the fixing assisting devices 61 and 62 in the surface of the supine position bucky 34. be able to.

  As described above, the subject holder 35, the head holder 36, the holder driving device 37, the stimulable phosphor plate 32, the slit shielding plate 31, the slit plate driving device 38, and the like necessary for radiographic image formation are placed in a supine position. 34 is configured as an attachment section 33 that can be attached to the head 34, and the radiation imaging system 100 is configured together with the radiation source 20, the radiation imaging apparatus 30, the radiation reading apparatus 40, the image processing apparatus 50, etc. The radiography system 100 can be provided without any trouble in the installation place without preparing a new room, while obtaining a tomographic image by rotating the subject M side.

  Therefore, even in hospitals and clinics where the scale is small and there is no interpretation doctor, the existing CR device can be applied to form a low-cost and high-quality 3D tomographic image without occupying space. It can be performed and the diagnostic ability can be greatly improved.

  The description in the present embodiment is an example of a suitable radiation imaging system 100 according to the present invention, and the present invention is not limited to this.

  For example, in the above description, a sinogram is recorded on the stimulable phosphor plate 32 by fixing the stimulable phosphor plate 32 and moving the slit shielding plate 31 in a predetermined direction at the time of photographing at each rotation angle. However, the present invention is not limited to this, and the slit shielding plate 31 may be fixed and the stimulable phosphor plate 32 may be moved in a predetermined direction to perform imaging at each rotation angle of the subject M.

  Further, the attachment unit 33 can be attached to a supine bucky 34 device of a type in which the storage phosphor plate and the reading mechanism unit are built in the bucky device.

  Further, instead of the CR cassette 28, a portable cassette FPD can be used.

  When the cassette FPD is used, reading and resetting operations are performed for each photographing, for example, only image data corresponding to FIG. 7B is extracted (other data is not deleted or read itself), and the next rotation angle At the time of photographing, it is possible to finally obtain a reconstructed image similar to the CR method by repeating the extraction of image data of only the region where the extraction region is shifted by the distance d. The plate driving device 38 is unnecessary, and the mechanism is simplified and preferable.

  Alternatively, continuous two-dimensional projection data may be acquired using an FPD capable of collecting a moving image such as fluoroscopy and the patient support apparatus of the present invention, and imaging may be performed as a cone beam CT. At this time, the FPD capable of collecting moving images may be portable or may be a device attached to the supine position bucky 34.

  Further, although the X-ray irradiation method is described as a cone beam, it may be configured such that a X-ray is used as a fan beam and the number of slits is one by using a shielding unit such as a diaphragm or a collimator. Further, with this configuration, the CR cassette 28 is replaced for each cross-sectional imaging, the subject M is returned to the start position, and the start position of the slit shielding plate 31 is changed for each CR cassette 28, so that An image of the cross section can be obtained. This method can increase the proportion of the X-ray dose irradiated to the plate in the X-ray dose that the patient is exposed to, so that the patient's exposure dose is reduced.

  Further, in the case of a type of radiation source that continuously generates X-rays at a predetermined cycle, the subject M is moved by a predetermined rotation angle (α) and the slit shielding plate 31 is moved by a predetermined amount (movement amount d). By continuously controlling the irradiation timing and the irradiation timing, such as automatically starting the movement to the next phase when the irradiation is detected, it is possible to continue shooting.

  In addition, the detailed configuration and detailed operation of each device or component constituting the radiation imaging system 100 according to the present embodiment can be set as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 10 Controller 20 Radiation source 28 CR cassette 29 Examination table 30 Radiation imaging device 31 Slit shielding plate 32 Storage phosphor plate 33 Attachment part 34 Supine bucky 35 Subject holder 36 Head holder 37 Holder drive device 38 Slit plate drive device 39 Fixing assisting device driving device 40 Radiation reading device 41 Reading unit 42 Signal processing unit 43 Primary storage unit 44 Communication unit 50 Image processing device 61 Fixing assisting tool 62 Fixing assisting tool 100 Radiation imaging system

Claims (6)

A radiation source for irradiating the subject with conical radiation;
A supine bucky capable of holding and holding the subject;
A CR detector for detecting the radiation transmitted through the subject;
A fixing means for positioning and fixing at least the head of the subject in the body axis direction of the subject on the supine position bucky, a first driving means for shifting the position of the fixing means around the body axis of the subject, and the subject Slit means having at least one rectangular opening in a direction orthogonal to the body axis direction of the specimen and shielding a part of the radiation; and second driving means for relatively moving the slit means and the CR detector; An attachment portion attachable to the supine bucky,
Each time the first driving means shifts the fixing means by a predetermined angle around the body axis of the subject, imaging is performed by irradiating radiation from the radiation source. After the irradiation, the second driving means is driven. And a control means for controlling to repeat the next photographing after the CR detector and the slit means are moved relative to each other by a predetermined amount,
The radiographic imaging system characterized in that, when the attachment unit is attached to the supine position bucky, the CR detector can take a sinogram that can reconstruct a CT image.   The radiographic system according to claim 1, wherein the control unit is provided in the attachment unit.   The radiation imaging system according to claim 1, wherein the attachment unit is detachable from the recumbent bucky.   The radiation imaging system according to any one of claims 1 to 3, wherein the first driving unit is capable of shifting the position of the fixing unit in both forward and reverse directions around the body axis of the subject.   The radiation imaging system according to claim 1, wherein the fixing unit positions and fixes the trunk of the subject.   6. The radiographic system according to claim 1, further comprising: a fixing auxiliary tool configured to be able to appear and retract from the supine position bucky surface, and the amount of appearance to be controlled by the control unit.

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