JP2005261666A - Radiographic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform radiographing by irradiation with X-rays vertically downwards in the area of the almost entire surface of a top plate and to perform radiographing from various angles other than that. <P>SOLUTION: A rectangular frame body 24 is freely horizontally movably installed at the upper part of a bed 21, and the top plate 26 is provided on the frame body 24. At the lower part of the top plate 26, an X-ray image detector 27 is freely movably arranged. The X-ray image detector 27 is made freely horizontally movable to the frame body 24 by a carriage 30. The carriage 30 is composed of a tray 30a for detachably supporting the X-ray image detector 27 and a carriage lower part 30b, and the tray 30a and the carriage lower part 30b are fixed to each other and integrated at the time of normal radiographing. At the time of detaching the X-ray image detector 27, the tray 30a is moved to the carriage lower part 30b and the X-ray image detector 27 and the tray 30a are taken out from an opening part 33 to the outside of the frame body 24. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a radiographic imaging apparatus that detects an intensity distribution of radiation such as X-rays transmitted through a subject such as a human body using an image detector.

  Conventionally, a so-called film / screen method is known as the most general imaging method for X-ray imaging. This film / screen method is a method of photographing by combining a photosensitive film and a phosphor having sensitivity to X-rays.

  As a second imaging method, a so-called computed radiography (CR) method has been put into practical use. This computed radiography method is a method in which a transmission image of radiation that has passed through a subject is accumulated as a latent image in a phosphor, and the latent image is read by irradiating excitation light later.

  Further, with the recent progress of semiconductor process technology, as a third imaging method, an apparatus for imaging X-ray images using a semiconductor sensor has been developed. The radiographic imaging system using this semiconductor sensor has an advantage that it can record an image of a very wide radiation exposure range as compared with a radiographic system using a conventional silver salt photograph.

  That is, X-rays in a wide dynamic range are read by a photoelectric conversion means and converted into an electric signal, and then a radiographic image is converted into a visible image on a recording material such as a photographic photosensitive material or a display device such as a CRT based on the electric signal. By outputting, it is possible to obtain a radiation image that is hardly affected by fluctuations in the exposure amount of radiation.

  FIG. 10 is a schematic view of a radiographic imaging system using this semiconductor sensor. The X-ray imaging apparatus 1 on which a subject is placed has a detection surface in which a plurality of photoelectric conversion elements are arranged in a two-dimensional manner. They are referred to as flat detectors, flat panels, and the like.

  X-rays emitted from the X-ray generator 3 disposed above the subject S are detected by the X-ray detection sensor 2 after passing through the subject. The image signal output from the X-ray detection sensor 2 is subjected to digital image processing in the image processing means 4 and then visualized and displayed on the monitor 5 as an X-ray image.

  Moreover, when imaging using the X-ray detection sensor 2 as described above, for example, as shown in Patent Document 1, various types of imaging apparatuses have been used so far to fix the detection means and the subject. Has been proposed.

Japanese Patent Laid-Open No. 2003-38472 (page 5-6, FIG. 1)

  FIG. 11 shows an X-ray imaging apparatus using a conventional X-ray detection sensor. A lifting platform 11 is provided on a floor surface, and a subject is placed on the lifting platform 11 via a support mechanism 12. A rectangular top plate 13 is fixed. A carriage 16 that holds an X-ray imaging unit 15 is supported on the inner frame of the top plate 13 via a support mechanism 14 so as to be movable in the longitudinal direction of the top plate 13. The carriage 16 is supported by a support mechanism 17 so as to be movable in the short direction of the top plate portion 13.

  Further, an X-ray tube 19 is suspended from the ceiling of the radiographing room via a suspension mechanism 18 on the top plate portion 13. With such a configuration, the top plate portion 13 on which the subject is placed is moved in a horizontal plane to be positioned with respect to the X-ray tube 19, and the X-ray imaging unit 15 is disposed almost over the entire top plate portion 13. It is possible to move and to take almost the whole body of the subject on the top plate part 13 as an imaging target.

  In the above-described conventional example, the imaging range can be expanded by moving the X-ray imaging unit 15 over almost the entire area of the top plate unit 13, but for example, X-rays are not irradiated from the top to the bottom, but are horizontal. It is not possible to deal with irradiation in a direction or an oblique direction.

  In the above-described conventional example, the X-ray imaging unit 15 may not be arranged in a suitable position as described above, and it is necessary to perform imaging while fixing a general film cassette at a position away from the top plate unit 13. is there. Accordingly, equipment relating to the X-ray detection sensor and developing equipment relating to the film cassette are required, which increases the equipment and complicates the operator's work.

  Further, in order to photograph a wide range of photographing areas, a general film cassette can be loaded with a plurality of films arranged in a long cassette, but this is not possible with the above-described conventional example.

  An object of the present invention is to provide a radiographic image capturing apparatus that eliminates the above-mentioned problems and enables a radiographic image detector to be taken out and imaged from various directions.

  In order to achieve the above object, a radiographic imaging apparatus according to the present invention includes a bed provided with a top plate portion on which a subject is placed, a radiographic image detector that detects an intensity distribution of radiation transmitted through the subject, and the radiation And a support portion that supports the image detector at a lower position of the top plate portion, and the support portion is configured to allow the radiation image detector to be connected to and detached from the top plate portion.

  According to the radiographic image capturing apparatus of the present invention, not only the X-ray is irradiated downward to make the entire surface of the top plate an imaging range, but also the radiographic image detector is taken out of the bed and placed at a required position. Thus, shooting from various directions becomes possible.

  Further, if a mechanism for discharging the image detector to the outside of the top plate portion is provided, the radiation image detector can be quickly taken out without a complicated operation.

  Furthermore, if the guide track in the longitudinal direction of the moving support mechanism of the image detector is provided in the longitudinal frame of the top plate portion, the mechanism is simplified.

  The image detector has a configuration in which a plurality of detectors can be combined and separated, and can be combined at the inside and outside of the top panel to shoot a long shooting range at once, or it can be divided and shot. By doing so, it is possible to shoot at various angles and to shoot at a long angle with the same image detector, which until now had to be based on a film cassette.

  The present invention will be described in detail based on the embodiment shown in FIGS.

  FIG. 1 is a perspective view of the X-ray imaging apparatus according to the first embodiment, and FIG. 2 is a cross-sectional view. A bed 21 that is a liftable floating table is provided in the imaging room. The bed 21 has a structure in which the upper surface of the bed 21 can be moved up and down with respect to the floor, and the side surface of the base 22 is covered with, for example, three covers 23 a to 23 c. On the upper part of the base 22, a rectangular frame 24 is provided with two pairs of rails 25 a and 25 b in the short direction indicated by the arrow A, and a rail (not shown) provided at a joint between the long side portion of the frame 24 and the rail 25 b. It is installed so that it can move horizontally in the lateral direction and the longitudinal direction. A top plate 26 is provided on the frame 24 to lie down the subject. The top plate 26 is made of a material having a high X-ray transmittance such as acrylic, polycarbonate, carbon, or wood. .

  An X-ray image detector 27 is movably disposed below the top plate 26. The X-ray image detector 27 is composed of a large solid-state imaging device called a flat panel sensor, and incorporates an image detection unit having a detection surface with a size of about 43 cm × 43 cm, for example. This image detection unit is manufactured using, for example, a semiconductor manufacturing process technique, and a plurality of photoelectric conversion elements or X-ray detection elements are arranged in a two-dimensional matrix.

  The X-ray image detector 27 is disposed on the upper surface of the cover member 28 made of a material having a high X-ray transmittance, and cooperates with the cover member 28 to enclose the above-described image detection unit in a light-tight manner. And a housing 29. The X-ray image detector 27 is urged so as to contact the lower surface of the top plate 26, and the upper surface is finished to be smooth so as to reduce the frictional force generated at the contact portion with the top plate 26 as much as possible. Note that this frictional force can be reduced by interposing a rolling member between the X-ray image detector 27 and the top plate 26.

  Further, a scattered radiation removal grid (not shown) can be inserted between the X-ray image detector 27 and the top plate 26 as necessary. This grid can be inserted and retracted via a mechanism (not shown), and it is preferable to select insertion or withdrawal according to the subject.

  The X-ray image detector 27 is held on the frame body 24 by a holding mechanism 32 including a carriage 30 and two pairs of rails 31 facing the short side direction that support the carriage 30. The carriage 30 includes a tray 30a that detachably supports the X-ray image detector 27 and a carriage lower part 30b. During normal imaging, the tray 30a and the carriage lower part 30b are fixed and integrated. The tray 30a is supported so as to be slidable in the short direction with respect to the carriage lower portion 30b, and can be moved with respect to the carriage lower portion 30b when an X-ray image detector 27 described later is taken out. An opening 33 through which the X-ray image detector 27 and the tray 30a can pass at the time of taking out is provided on the side of the frame 24.

  The carriage 30 is supported by the rail 31 as described above and is slidable in the short direction. Further, each end portion of the rail 31 is supported so as to be slidable in the longitudinal direction along a guide groove 34 provided on the inner side in the longitudinal direction of the frame body 24.

  As described above, the X-ray image detector 27 is supported by the holding mechanism 32 so as to be movable over almost the entire area of the lower surface of the top plate 26. The conventional carriage moving mechanism can be simplified without impairing the function.

  Above the bed 21, an X-ray tube 41 is supported on a ceiling by a suspension mechanism 42, and the X-ray tube 41 emits X-rays downward and can irradiate a subject lying on the bed 21. Has been. The suspension mechanism 42 is supported by a horizontal movement member 42a that is movably supported in the short and long directions of the bed 21 indicated by arrows A and B, and is supported by the horizontal movement member 42a so as to be movable in the vertical direction indicated by arrow C. It is comprised from the up-and-down moving member 42b made. The X-ray tube 41 is attached to the lower part of the vertical movement member 42b and can be moved in the three-dimensional directions A, B, and C by the suspension mechanism 42.

  FIG. 3 is a configuration diagram of the holding mechanism 32 and the electric circuit in the bed 21, and particularly shows a configuration related to the moving mechanism in the short direction of the carriage 30, and the longitudinal direction is the same configuration, but is omitted in the drawing. . A drive source 51 such as a DC motor or a pulse motor is provided on the side of the rail 31, and a drive pulley 52 is fixed to the drive shaft of the drive source 51. A driven pulley 54 is provided above the drive pulley 52 in the drawing via a fixed base 53. The driving pulley 52 and the driven pulley 54 are connected by a timing belt 55 along the rail 31, and a part of the timing belt 55 is fixed to the carriage 30. The driven pulley 54 has a biasing means (not shown), and is configured to apply a desired tension to the timing belt 55 by the biasing means. Thus, for example, when the drive pulley 52 rotates to the right, the X-ray image detector 27 on the carriage 30 moves upward in the drawing, and when it rotates to the left, it moves downward.

  A scale portion 56 of the linear encoder is fixed along the rail 31, and a sensor portion 57 is attached to the carriage 30. The linear encoder includes a scale unit 56 and a sensor unit 57. The sensor unit 57 reads the pattern of the scale unit 56, thereby generating a pulse signal corresponding to the movement of the carriage 30 and a signal indicating the movement direction and a pulse. Are added and subtracted to detect the position of the carriage 30.

  The drive source 51 is connected to a controller 58, and a comparison circuit 59 is connected to the controller 58. The comparison circuit 59 includes an output of the sensor unit 57 that detects the position of the X-ray image detector 27 in the short direction and an output of the short direction position sensor 60 that detects the position of the X-ray tube 41 in the short direction. It is connected.

  Similarly, the controller 58 includes each drive source of the suspension mechanism 42, a position sensor such as the position sensor 60 corresponding to each drive direction, a longitudinal position sensor that detects the longitudinal position of the X-ray image detector 27, and a base. A drive source for changing the height of the upper surface of the table 22, a vertical position sensor for detecting the height of the upper surface, and each position sensor for detecting each position in the short and long directions of the frame 24 are connected. Has been.

  Further, the controller 58 is provided with or connected to a switch input unit for operating each unit, setting a series of controls, and the like, and the controller 58 is connected to the X-ray tube 41 and the X-ray tube 41 based on these operations or settings. Each part is controlled so as to have a predetermined positional relationship with the line image detector 27.

  For example, when the position of the X-ray image detector 27 is deviated from a predetermined position corresponding to the position of the X-ray tube 41, the controller 58 outputs a signal from the comparison circuit 59, for example, the X-ray image detector 27. Each drive source such as the drive source 51 is controlled based on a signal indicating a comparison result such as a signal indicating a positional deviation amount (vector amount) in each moving direction, and the position of the X-ray image detector 27 is determined as an X-ray tube. It is made to correspond to the predetermined position corresponding to 41.

  Although the case where the X-ray image detector 27 is driven to a predetermined position corresponding to the X-ray tube 41 has been described here, the X-ray tube 41 is driven to a predetermined position corresponding to the X-ray image detector 27. Alternatively, the X-ray tube 41 and / or the X-ray image detector 27 can be driven to a predetermined position corresponding to a predetermined imaging target region of the subject.

  FIG. 4 is a block circuit configuration diagram of an imaging system including the X-ray image detector 27 and the X-ray tube 41. The X-ray image detector 27 is connected to a control unit 71. The control unit 71 includes a control unit 72, an image processing unit 73, a communication unit 74, and the like. The control unit 72 has various setting parameter storage units 75. ing. An operation means 76, a monitor 77 and an X-ray generation means 78 are connected to the control means 72, and an X-ray tube 41 is connected to the output side of the X-ray generation means 78. In addition, an image database 80 and an interpretation workstation 81 are connected to the communication means 74 via a network 79.

  The image data acquired by the X-ray image detector 27 is transferred to the image processing means 73 of the control unit 71 and subjected to desired processing, and the processed image data is transferred to the network 79 in the hospital via the communication means 74. It is supposed to be sent.

  In the present embodiment, the X-ray image detector 27 is arranged below the top plate 26 in the configuration described above, and an X-ray image of the subject can be taken. The device 27 can be taken out from under the top plate 26 and placed at an arbitrary position such as on the top plate 26.

  FIG. 5 is a flowchart of the take-out operation in this case. When the operator takes out the X-ray image detector 27 and performs imaging, the operator inputs a take-out command from the operation means 76 (step S501). This command is transmitted to the carriage position control means of the bed 21 through the control means 72, and the longitudinal position of the carriage 30 is detected (step S502). Since the carriage 30 can discharge the X-ray image detector 27 at a specific position in the longitudinal direction, for example, at the center, the information on the discharge position stored in advance can be compared with the detected current position in the longitudinal direction. The difference is calculated (step S503).

  When the difference is not 0, that is, when the carriage 30 is not located at the central portion in the longitudinal direction as the discharge position, a desired direction and distance in the longitudinal direction are calculated by the controller 58, and the carriage 30 is moved (step S504). When the discharge position in the longitudinal direction coincides with the position of the carriage 30, the movement in the longitudinal direction is stopped (steps S505 and S506).

  Subsequently, the carriage 30 is moved to the near side in the short direction (step S507). When the lower part of the carriage 30 reaches the forefront part of the movement range, the tray 30a releases the restraint on the carriage 30 that has moved together so far, and the carriage 30 remains stopped and only the tray 30a moves further forward. A part of the X-ray image detector 27 on which the tray 30a is placed passes through the opening 33 of the front frame 24 and stops in a state of being exposed to the outside of the frame 24 (steps S508 and S509).

  FIG. 6 is a perspective view of this state, FIG. 7 is a cross-sectional view, and the operator can take out the X-ray image detector 27 by pulling the X-ray image detector 27 obliquely upward from the tray 30a as shown by a one-dot chain line in FIG. Yes (step S510). The taken-out X-ray image detector 27 is fixed to a subject at a desired position using an appropriate fixture or the like, and is irradiated with X-rays from a desired direction. The part which cannot be image | photographed can be image | photographed (step S511).

  FIG. 8 shows an example of such a case, and is an explanatory diagram in the case of taking a side view with the taken-out X-ray image detector 27 vertically fixed on the top plate 26. In this case, the X-ray image detector 27 may communicate with the control unit 71 via a wired communication or wirelessly.

  As described above, by providing the take-out mechanism from the bed 21 of the X-ray image detector 27, it is possible to perform imaging from various angles that were impossible in the conventional example.

  FIG. 9 is a perspective view of the second embodiment. The bed 21 ′ is different from the bed 21 of the first embodiment in that two X-ray image detectors 27 a and 27 b are mounted on the carriage 30 instead of the X-ray image detector 27.

  The X-ray image detectors 27a and 27b are arranged adjacent to the two X-ray image detectors 27 of the first embodiment, and both can be used at the same time for imaging. Either one can be selected and used alone. You can shoot with It is also possible to instantaneously move a distance corresponding to a non-photographable portion existing between both detection areas after photographing one, and photograph an area that touches or overlaps the previously photographed area on the other.

  Further, the X-ray image detectors 27a and 27b can be taken out of the bed 21 'by moving the tray 30a to a predetermined position in the same procedure as in the first embodiment. When taking out the X-ray image detectors 27a and 27b to the outside, the two X-ray image detectors 27a and 27b can be combined and taken out, or only one of them can be taken out and photographed alone. In this way, not only the same effects as in the first embodiment can be obtained, but also a long shooting range that cannot be realized in the first embodiment can be shot.

  Although the example in which the two X-ray image detectors 27a and 27b are adjacent to each other has been described, other numbers of divisions may be used, and a plurality of X-ray image detectors having different specifications may be combined.

  Needless to say, the X-ray imaging apparatuses according to the first and second embodiments can be variously modified without departing from the scope of the claims. For example, although the bed 21 is a liftable floating table, if the table 21 has a top plate 26 that can lie on the subject, the table 26 is a table that does not move the top plate 26 or a table that does not move the top plate 26 in the horizontal direction. You can also. The bed 21 may be a so-called tilting type that can support the top plate 26 in an inclined state.

  Further, instead of the bed 21, a surgical table, an ICU (Intensive Care Unit) bed, an emergency stretcher, or the like can be used. In this case, it becomes possible to quickly respond to a subject who needs urgency, and an X-ray image can be easily and quickly compared with the case where a cassette is inserted under the subject and imaged. Can be obtained.

  In this embodiment, a medical X-ray imaging apparatus for imaging a subject using X-rays has been described. However, an X-ray imaging apparatus for imaging another subject or other radiation is used. It is also possible to apply to a photographing apparatus.

  Further, it can be combined with other devices, and for example, it can be combined with a surgical C-arm type device or a fluoroscopic device equipped with a television device with II (Image Intensifier).

1 is a perspective view of an X-ray image capturing apparatus according to Embodiment 1. FIG. It is a cross-sectional view. It is a block diagram of a holding mechanism and an electric circuit. It is a block circuit block diagram of the system of an X-ray imaging apparatus. It is a flowchart figure of an operation procedure. It is a perspective view in the state where an X-ray imaging device was taken out. It is a cross-sectional view of a state where the X-ray imaging apparatus is taken out. It is a perspective view after taking out an X-ray imaging device. 6 is a perspective view of an X-ray imaging apparatus according to Embodiment 2. FIG. It is explanatory drawing of the conventional imaging | photography system. It is a perspective view of schematic structure of the conventional X-ray imaging device.

Explanation of symbols

21 Bed 22 Base 24 Frame 26 Top plate 27 X-ray image detector 30 Carriage 32 Holding mechanism 33 Opening 41 X-ray tube

Claims (5)

  A bed provided with a top part for placing a subject, a radiation image detector for detecting an intensity distribution of radiation transmitted through the subject, and a support part for supporting the radiation image detector at a lower position of the top part The radiographic image capturing apparatus according to claim 1, wherein the support unit is configured to allow the radiographic image detector to be connected to and detached from the top plate unit.   The top plate movement mechanism which makes the said top plate part movable in a horizontal direction is provided, The detector moving mechanism which makes the said radiographic image detector movable in a horizontal direction with respect to the said top plate part is provided. Radiographic imaging device.   The radiographic image capturing apparatus according to claim 1, further comprising a mechanism that discharges the radiographic image detector from below the top plate when the radiographic image detector is detached from the support.   The radiographic imaging apparatus according to claim 2, wherein a guide portion in a longitudinal direction of the top plate portion of the detector moving mechanism is provided on a frame body of the top plate portion.   The radiographic image capturing apparatus according to claim 1, wherein the radiographic image detector includes a plurality of detectors configured to be freely combined and divided, and can be imaged in both the combined and divided states.

Images