JP2007037837A - Radiographic system and image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable the discrimination of the gravity orientation at the time of taking radiographs for an radiographic diagnosis. <P>SOLUTION: This radiographic system 1 comprises an X-ray-emitting section 104 for emitting X-rays, an X-ray receiving section 105 and a solid-state image pick-up element 1051 for detecting the X rays generated by the X-ray generating section 104 and then converting them into electric signals, a gravity direction detecting section 1050 for detecting the gravity direction concerning the X-ray receiving section 105 when the X-ray receiving section 105 detects the X rays, and a radiographic system control section 101 for producing image data based on the electric signals obtained by the X-ray receiving section 105. The radiographic system control section 101 adds the gravity information on the gravity orientation detected by the gravity direction detecting section 1050 to the produced image data to produce diagnostic image data. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a radiographic technique and a display technique thereof, and is particularly suitable for radiography in the medical field.

  Currently, in the medical field, “image diagnosis” in which diagnosis is performed using an image obtained from a radiographic apparatus is actively performed. As a radiation imaging apparatus, various apparatuses such as a simple X-ray apparatus, CT, and MRI have been developed and put into practical use. In image diagnosis using such radiographic images, not only physically visible information such as the presence or absence of a tumor and the state of a fracture, but also the direction of gravity may be important.

For example, when performing fluoroscopic imaging, the bed is tilted in various directions in order to attach the contrast agent to the examination site using gravity. Patent Document 1 proposes a method of displaying the direction of gravity on the display monitor so that the contrast agent can be appropriately attached while performing such photographing while looking at the display monitor of the fluoroscopic image. .
JP-A-6-169907

  There are two types of imaging that are generally performed in simple X-ray imaging: supine position photography in which a subject lies on a bed and standing position photography in which the subject stands upright. When the two images are compared, the same image is not always obtained because the load direction on the organ is different even if the imaging region is the same. In addition, since the adhesion state of the organ can be determined depending on the degree of gravity, the direction of gravity at the time of imaging has an important diagnostic significance. This is true not only for simple X-ray imaging but also for the relationship between a general CT apparatus and a standing CT apparatus.

  In the method described in Patent Document 1, only the gravity direction during fluoroscopic imaging is displayed on a monitor in order to facilitate the attachment of a contrast agent, and the gravity direction is not recorded for an image obtained by the imaging. Furthermore, since the gravitational direction is calculated by the bed position sensor and the camera position sensor, it cannot be used for shooting without a bed or shooting without a TV camera, and only with an X-ray sensor like a simple X-ray imaging device. It cannot be applied to the configuration in which

  As described above, the conventionally proposed method cannot acquire the direction of gravity from the image obtained by the photographing apparatus and effectively use it for diagnosis.

  The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to determine the direction of gravity at the time of shooting in diagnosis using a shot image.

In order to achieve the above object, a radiation imaging system according to an aspect of the present invention has the following arrangement. That is,
Radiation generating means for irradiating radiation;
Radiation detecting means for detecting radiation generated by the radiation generating means and converting it into electrical signals;
A gravitational direction detecting means for detecting a gravitational direction applied to the radiation detecting means at the time of detection of radiation by the radiation detecting means;
Generating means for generating image data based on the electrical signal obtained by the radiation detecting means;
And adding means for adding gravity information indicating the gravity direction detected by the gravity direction detecting means to the image data generated by the generating means.

  According to the present invention, it is possible to easily determine the direction of gravity at the time of photographing in diagnosis using a photographed image.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

<First Embodiment>
FIG. 1 is a diagram illustrating a hardware configuration of the radiation imaging system according to the first embodiment. The radiation imaging system of the present embodiment performs X-ray imaging using X-rays as radiation (hereinafter referred to as X-ray imaging system 1). Reference numeral 100 denotes a subject that is an imaging target of X-ray imaging. The system control unit 101 controls the entire X-ray imaging system 1. The console 102 includes general input / output devices for X-ray imaging such as a keyboard, a mouse, a display, and an exposure button. The operator can use the console 102 to give various instructions to the X-ray imaging system control unit 101 such as setting of imaging conditions and instructions for exposure. The X-ray generator control unit 103 controls the X-ray generator 104. The X-ray image receiving unit 105 receives X-rays emitted from the X-ray generation unit 104 and transmitted through the subject 100, and converts them into electrical signals to generate image signals.

  The operator arranges the subject 100 and the X-ray image receiving unit 105 so that the X-ray image receiving unit 105 images the target region of the subject 100 and uses the console 102 to set the imaging region before imaging. Set up. When the operator presses the exposure button on the console 102, the X-ray generation unit 104 is instructed to perform exposure, and the X-ray generation unit 104 emits X-rays. The X-ray image receiving unit 105 generates an image signal based on the X-rays irradiated from the X-ray generation unit 104 and reaching the X-ray image receiving unit 105. The X-rays that have reached the X-ray image receiving unit 105 include X-rays transmitted through the subject 100 (transmission X-rays), and an X-ray image is generated by imaging the transmitted X-rays.

  The X-ray image receiving unit 105 receives X-rays and generates an electric signal (image signal) corresponding to the X-ray dose, and a gravity direction detection unit 1050 that detects the direction of gravity load on the X-ray image receiving unit 105. It comprises. As the gravity direction detector 1050, for example, an acceleration sensor is used. The image signal acquired by the solid-state imaging device 1051 and the gravity information acquired by the gravity direction detection unit 1050 are transferred to the signal reading control unit 1010 of the X-ray system control unit 101. The signal reading control unit 1010 is managed by the CPU 1016. A nonvolatile storage device 1011, a RAM 1012, a ROM 1013, a LAN interface (LAN / IF) 1014, and a disk interface (DISK / IF) 1015 are connected to the CPU 1016 via a system bus 1017. In the present embodiment, an image display device described later with reference to FIG. 6 and the like is connected via the LAN / IF 1014. As the nonvolatile storage device 1011, for example, a hard disk is used. The image signal input to the signal reading control unit 1010 is temporarily stored in the RAM 1012 together with gravity information. The image signal and gravity information stored in the RAM 1012 are subjected to various processes by the CPU 1016 and then formed into a final diagnostic image.

  Next, detection of the inclination of the X-ray image receiving unit 105 with respect to the direction of gravity will be described with reference to FIG. FIG. 2 defines an axial direction serving as a reference when detecting the gravitational direction of the X-ray image receiving unit 105. Reference numeral 200 denotes an X-ray sensor, which is the X-ray image receiving unit 105 itself. The axial direction defined in FIG. 2A is an axial direction that serves as a reference for the output value of the gravity direction detector 1050 used to detect the gravity direction. 2A, the image receiving surface of the X-ray sensor 200 (the image receiving surface of the solid-state imaging device 1051) is made to coincide with the XY plane, and the normal direction of the image receiving surface is the Z axis. The gravity direction detection unit 1050 can be an inclination sensor or a gravity sensor. In the present embodiment, a general three-axis acceleration sensor is used as the gravity direction detection unit 1050. The triaxial acceleration sensor detects respective accelerations with respect to the X, Y, and Z axes defined in FIG. 2, and uses the value as gravity direction information. For example, when the X-ray sensor 200 is arranged as shown in FIG. 2B, gravity of 1 [G] is applied as shown by 201. Therefore, the acceleration value in the X-axis direction is 0, the acceleration in the Y-axis direction is 1 [G] × sin θ (202 in FIG. 2), and the acceleration in the Z-axis direction is 1 [G] × cos θ (203). The The gravity information obtained in this way is transferred to the signal reading control unit 1010 of the X-ray imaging system control unit 101 together with the image signal obtained by the solid-state imaging device 1051.

  In this embodiment, for the sake of simplicity, an example in which the X-ray sensor is tilted so that the reference X-axis of the X-ray sensor 200 is orthogonal to the gravitational direction is shown, but the gravitational direction is tilted with respect to all axes. Needless to say, gravity information can be acquired in the same way. Further, the reference axis defined in FIG. 2 is not limited to this, and any reference axis may be used as long as the reference axis can be defined in a certain direction.

  Next, processing performed in the X-ray image receiving unit 105 when performing X-ray imaging will be described with reference to FIG. FIG. 3 is a flowchart for explaining the operation of the X-ray image receiving unit 105 when X-ray imaging is performed in the X-ray imaging system 1. The X-ray image receiving unit 105 acquires an image signal based on transmitted X-rays using the solid-state imaging element 1051 and detects the direction of gravity using the gravity direction detection unit 1050.

  First, in step S300, the X-ray image receiving unit 105 enters a standby state for receiving X-rays. In this state, the X-ray image receiving unit 105 notifies the X-ray imaging system control unit 101 by a drive notification signal that the solid-state imaging device 1051 can receive X-rays and form an image. On the other hand, when the X-ray imaging system control unit 101 detects that the exposure button on the console 102 is pressed (exposure instruction), the X-ray image receiving unit 105 receives X-rays according to the drive notification signal of the solid-state imaging device 1051 and receives an image. It is confirmed whether or not it is in a state that can be converted into a state. If the confirmation is obtained by the drive notification signal, the X-ray imaging system control unit 101 sends an exposure signal to the X-ray generation device control unit 103. Receiving the exposure signal, the X-ray generator control unit 103 drives the X-ray generator 104 to start X-ray irradiation.

  The exposure signal is also transmitted to the X-ray image receiving unit 105. In step S <b> 301, when the X-ray image receiving unit 105 receives this exposure signal, the X-ray image receiving unit 105 starts reading transmitted X-rays by the solid-state imaging device 1051. In step S302, the solid-state image sensor 1051 reads transmitted X-ray information to obtain an image signal. In step S303, the gravity direction detection unit 1050 detects the acceleration value with respect to each reference axis of the X-ray sensor 200, and generates gravity information based on the acceleration value. The gravitational direction may be detected by detecting the gravitational direction of the X-ray sensor 200 at the time of imaging, and may be any timing immediately before, immediately after, or during the reading of the X-ray information in step S302. In step S304, the image signal acquired in step S302 and the gravity information generated in step S303 are transferred to the signal reading control unit 1010 of the X-ray imaging system control unit 101, and the process ends.

  Next, processing until the diagnostic image is formed from the image signal and gravity information transmitted from the X-ray image receiving unit 105 by the X-ray imaging system control unit 101 will be described with reference to the flowchart of FIG.

  In step S <b> 400, the signal reading control unit 1010 reads the image signal acquired by the X-ray image receiving unit 105. After the image signal is read in step S400, the signal reading control unit 1010 reads gravity information from the X-ray image receiving unit 105 in step S401. In addition, since step S400 and step S401 are steps which read an image signal and gravity information, it cannot be overemphasized that either process may be performed first.

  In step S402, gradation conversion, noise removal, sharpening processing, and the like are performed on the image read in the image signal reading step in step S400. These image processes are processes generally performed in X-ray imaging, and detailed description thereof is omitted. In step S403, incidental information to be added to the image is generated. In the present embodiment, it is important that information such as patient information and examination information is created as supplementary information, and the gravity information read in step S401 is also created as part of the supplementary information. In step S404, a final diagnostic image is generated using the image signal after image processing generated in step S402 and the incidental information generated in step S403. The image generated in step S404 is preferably based on a format called DICOM (Digital Imaging and Communications in Medicine) which is a medical image standard.

  FIG. 5 shows a data configuration example of the diagnostic image. The diagnostic image 500 of this embodiment includes a header portion 501 and an image data portion 502. In the header portion 501, in addition to the description such as the size of the image data portion 502, the accompanying information 503 described above is described. The accompanying information 503 includes gravity information 504. In the image data portion 502, the image data processed in step S402 is recorded.

  The diagnostic image 500 obtained as described above is transferred to the information terminal or image server connected to the network with respect to the X-ray imaging system control unit 101, or directly such as MO, DVD-RAM, CD-ROM or the like. Output to portable media.

  Next, an image display apparatus that displays image data obtained by the X-ray imaging system 1 and its processing will be described. FIG. 6 is a hardware configuration diagram of the image display device 6 that displays image data created by the X-ray imaging system 1. In the present embodiment, the X-ray imaging system control unit 101 of the X-ray imaging system 1 and the image display device 6 are separated from each other by a network. However, they may be integrated. For example, the configuration and functions of the X-ray imaging system control unit 101 image display device 6 may be included.

  The image display device 6 includes a control unit 600, an input unit 601, and a display unit 602. The control unit 600 has a general information terminal configuration. For example, the control unit 600 includes a nonvolatile storage device 6000 such as a hard disk, a RAM 6001, a ROM 6002, a LAN / IF 6003, and a DISK / IF 6004, which are connected to the CPU 6005 via the system bus 6006. The input unit 601 includes an input device for an operator to instruct the control unit 600. Examples of the input device include a mouse and a keyboard. The display unit 602 is a display monitor such as a CRT or a liquid crystal display. The above-described diagnostic image 500 is displayed by the image display device 6 as described above.

  FIG. 7 is a block diagram showing a functional configuration of the X-ray image display device 6. The image receiving unit 700 receives the diagnostic image 500 transferred from the X-ray imaging system control unit 101 via the network, or reads the diagnostic image 500 written in the portable storage medium, thereby The image 500 is taken into the control unit 600. The image data transferred via the network is received by the LAN / IF 6003. Further, the image data written in the portable storage medium is read by the DISK / IF 6004. The image storage unit 701 stores the image data captured by the image receiving unit 700 in, for example, the nonvolatile storage device 6000. The supplementary information reading unit 702 reads supplementary information 503 of the image data stored in the image storage unit 701. Further, the gravity information reading unit 703 reads the gravity information 504 from the incidental information 503 acquired by the incidental information reading unit 702. The gravity display information creation unit 704 performs a process of making the gravity information 504 read by the gravity information reading unit 703 into a display form that is easy for the operator to understand. The image display unit 705 displays additional information of the image including image data and gravity information on the display unit 602. Each function described above is realized by the CPU 6005 executing a program stored in the nonvolatile storage device 6000.

  FIG. 8 is a flowchart showing processing from when the image display device 6 receives the diagnostic image 500 to when the image is displayed. In step S800, the image receiving unit 700 of the X-ray display apparatus acquires the diagnostic image 500 and stores it in the image storage unit 701. As described above, such image data is acquired by receiving image data transferred over an external network via the LAN / IF 6004 or by writing image data written on a portable storage medium. This is done by reading via / IF6004.

  In step S <b> 801, the incidental information reading unit 702 reads incidental information 503 of the diagnostic image 500 stored in the image storage unit 701. Subsequently, in step S802, it is confirmed whether or not the gravity information 504 exists in the incidental information 503 read in step S801. If it exists, the process proceeds to step S803, and if not, the process proceeds to step S805. In step S803, the gravity information reading unit 703 reads the gravity information 504 from the incidental information 503 read in step S801. In step S804, the gravity display information creation unit 704 converts the gravity information 504 read in step S803 into a display format that is easy for the operator to understand. In step S805, the image data is displayed on the image display unit 700, and the overlay information created in step S804 is also displayed.

  FIG. 9 is a diagram showing an example of image display by the image display device 6. Reference numeral 900 denotes image data captured by the X-ray imaging system 1. Reference numeral 901 denotes an incidental information display unit that displays gravity information 504 read as incidental information of the image data 900. FIG. 9 shows that a load of 0.631 G is applied in the X-axis direction, 0.707 G in the Y-axis direction, and 0.316 G in the Z-axis direction. Furthermore, in the display example of FIG. 9, a figure using a rectangular parallelepiped is displayed so that it can be more intuitively understood in which direction gravity is applied from these values. X, Y, and Z shown here indicate the reference axes defined in FIG. 2A, and the ratio of gravitational acceleration values obtained with respect to each reference axis matches the ratio of each side of the rectangular parallelepiped. It is displayed to do. That is, in the above-described example, the ratio of the lengths of the sides of the rectangular parallelepiped is X: Y: Z = 0.611: 0.707: 0.316. The direction of gravity is an arrow connecting coordinates (0, 0, 0) to (0.631, 0.707, 0.316). As described above, since the XY plane coincides with the imaging surface, the direction of gravity with respect to the image can be intuitively grasped by the arrow. In the present embodiment, a method of displaying a rectangular parallelepiped on the right side of the image data in order to indicate the direction of gravity has been described. However, it goes without saying that the display location and the display method are not limited as long as the display method can grasp the direction of gravity. Yes. Note that the display and non-display of the incidental information display unit 901 may be switched.

  As described above, according to the X-ray imaging system 1 and the image display device 6 of the present embodiment, the state of gravity acting on the X-ray sensor at the time of imaging can be added to the image data as supplementary information. It is displayed so that it can be easily grasped by the observer. For this reason, it is possible to know the state of the load on the subject at the time of shooting only from the image data.

Second Embodiment
In the first embodiment, an example (S403 and S404 in FIG. 4) in which the gravity information detected by the gravity direction detection unit 1050 is written as supplementary information of the image has been shown. is there. That is, in step S404, the gravity information is imaged, and the imaged gravity information is subjected to overlay processing on the image data that has been subjected to image processing in step S402 to obtain a diagnostic image. In this case, it is not necessary to describe the gravity information as supplementary information in step S403.

  FIG. 10 shows a display example of an image obtained when gravity information is directly written on the image. Reference numeral 1000 denotes an X-ray image acquired by the X-ray imaging system 1. Reference numeral 1001 denotes a gravity direction display unit that is overlaid on the X-ray image 1000 to indicate in which direction gravity is applied to the X-ray sensor when the X-ray image 1000 is taken. X, Y, and Z in this part indicate the reference axes defined in FIG. 2A, and are displayed so that the ratio of gravitational acceleration values obtained with respect to each reference axis matches the ratio of each side of the rectangular parallelepiped. Yes. For example, it is assumed that the acceleration value in the X-axis direction detected by the gravity direction detection unit is 0.632G, the acceleration value in the Y-axis direction is 0.707G, and the acceleration value in the Z-axis direction is 0.316G. In this case, the ratio of the lengths of the sides of the rectangular parallelepiped displayed on the gravity direction display unit 1001 is also X: Y: Z = 0.611: 0.707: 0.316. In addition, in 2nd Embodiment, although the method of displaying a rectangular parallelepiped in order to show a gravitational direction was shown, as long as it is a display method which can grasp | ascertain a gravitational direction, what kind of display method may be used.

  In the case of the second embodiment, the description of the gravity information 504 can be omitted from the diagnostic image 500 shown in FIG. Further, it is not necessary to provide the gravity information display function as described in the first embodiment in the image display device.

  In the second embodiment, the user may be able to specify the overlay position of gravity information. For example, the lower left (FIG. 10), upper left, lower right, upper right, etc. of the image can be designated via the console 102. In the gravity information overlay process in step S404 described above, the imaged gravity information is written at a position designated via the console 102.

  As described above, according to each of the above embodiments, the gravitational direction with respect to the X-ray sensor at the time of imaging is given to the captured image as incidental information or as an image. Therefore, the radiogram interpreter can know the state of the load on the subject at the time of photographing only by referring to the image, and can perform more advanced diagnosis by visually observing diagnostic information such as the state of the organ and the load state information. Become.

1 is a hardware configuration diagram of an X-ray imaging system according to an embodiment. It is an example which showed the reference axis for detecting the gravity direction with respect to the X-ray sensor which concerns on embodiment. It is the flowchart which showed a series of processes which the X-ray image receiving part at the time of X-ray imaging which concerns on embodiment performs. It is the flowchart which showed the process until it forms a diagnostic image from the image signal and gravity information which were acquired in the X-ray image receiver which concerns on embodiment. It is a figure which shows the example of a data structure of the diagnostic image by 1st Embodiment. It is a hardware block diagram of the image display apparatus which concerns on embodiment. It is the block diagram which showed the function structure of the image display apparatus which concerns on embodiment. It is a flowchart of the image display apparatus which concerns on embodiment. It is the figure which showed the example of an image display of the image display apparatus which concerns on embodiment. It is a figure explaining the image data in which gravity information is written as overlay information concerning a 2nd embodiment.

Claims (13)

Radiation generating means for irradiating radiation;
Radiation detecting means for detecting radiation generated by the radiation generating means and converting it into electrical signals;
A gravitational direction detecting means for detecting a gravitational direction applied to the radiation detecting means at the time of detection of radiation by the radiation detecting means;
Generating means for generating image data based on the electrical signal obtained by the radiation detecting means;
A radiation imaging system comprising: an adding unit that adds gravity information indicating a gravity direction detected by the gravity direction detecting unit to the image data generated by the generating unit.   The radiation imaging system according to claim 1, wherein the adding unit adds the gravity information as incidental information to the image data.   The radiographic system according to claim 1, wherein the adding unit generates an image representing a direction of gravity based on the gravity information, and superimposes the image on a predetermined position of the image represented by the image data. . First receiving means for detecting electrical radiation generated by the radiation generating means and receiving electrical signals from the radiation detecting means for converting into electrical signals;
A second receiving means for receiving gravity information indicating the direction of gravity from the gravity direction detecting means for detecting the direction of gravity applied to the radiation detecting means at the time of detection of radiation by the radiation detecting means;
Generating means for generating image data based on the electrical signal received by the first receiving means;
A radiation imaging control apparatus comprising: an adding unit that adds the gravity information received by the second receiving unit to the image data generated by the generating unit. Receiving means for receiving image data;
Reading the incidental information of the image data received by the receiving means, obtaining the gravity information representing the gravity direction at the time of shooting from the incidental information,
An image display apparatus comprising: display means for displaying the gravity information acquired by the acquisition means together with the image data.   The image display apparatus according to claim 5, wherein the display unit generates an image representing a direction of gravity based on the gravity information acquired by the acquisition unit, and displays the generated image together with the image data. A generation step of detecting radiation generated by the radiation generation means, obtaining an electrical signal from the radiation detection means for converting the radiation signal into an electrical signal, and generating image data based on the electrical signal;
An acquisition step of acquiring gravity information indicating a gravity direction at the time of detection of radiation by the radiation detection means from a gravity direction detection means for detecting a gravity direction applied to the radiation detection means;
A radiography control method comprising: an addition step of adding the gravity information acquired in the acquisition step to the image data generated in the generation step.   The radiation imaging control method according to claim 7, wherein the adding step adds the gravity information to the image data as supplementary information.   The radiographic imaging control according to claim 7, wherein the adding step generates an image representing a direction of gravity based on the gravity information and superimposes the image on a predetermined position of the image represented by the image data. Method. A receiving process for receiving image data;
Reading the auxiliary information of the image data received by the receiving means, obtaining the gravity information representing the gravity direction at the time of shooting from the auxiliary information,
A display control step of displaying the gravity information acquired by the acquisition means together with the image data on a display.   The image display method according to claim 10, wherein the display control step generates an image representing a gravity direction based on the gravity information acquired in the acquisition step, and displays the generated image together with the image data.   A control program for causing a computer to execute the method according to claim 7.   A storage medium storing the control program according to claim 12.

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