JP5052384B2 - Radiation imaging equipment - Google Patents

Description

  The present invention relates to a radiographic image capturing apparatus, and more particularly to a radiographic image capturing apparatus having a function of capturing a radiographic image by detecting radiation transmitted through a subject and simultaneously capturing a plurality of times of the same subject.

  Conventionally, in tomosynthesis imaging, a plurality of images (50 to 90 images) are continuously captured at a time, and then the images are reconstructed. A tomosynthesis imaging system that displays a rendered image based on a reconstructed image is known (Patent Document 1).

  A digital tomosynthesis system configured to acquire a plurality of projection radiation images of an object by moving an X-ray source along a locus located at a certain distance from a detector is known (Patent Document 2). ).

  In tomosynthesis shooting, it takes a very long time from shooting to display of the image. Therefore, when checking the shooting position after waiting for the display of the image, it is necessary to keep the subject person in the device for a long time. . Therefore, prior to tomosynthesis shooting, pre-shooting with a still image (pre-shot), displaying the pre-shot image, checking the shooting position and shooting conditions, and then performing tomosynthesis shooting, There is known a method for allowing a person who is a subject to be released from the apparatus without waiting for reconfiguration.

For example, a method for displaying a preview tomosynthesis image in a preview mode is known (Patent Document 3). In addition, a positioning method is known in which a patient is photographed by low-dose pre-shot and the position of the patient is determined (Patent Document 4).
JP 2005-182831 A JP 2005-13736 A JP 2007-50264 A JP 2003-164441 A

  However, with the techniques described in Patent Documents 3 and 4 above, the shooting position in the pre-shooting and the shooting position in the actual tomosynthesis shooting do not necessarily match, and thus the shooting position cannot be accurately confirmed. There is. In addition, there is a problem that the amount of exposure received by the person who becomes the subject increases by the pre-shooting.

  The present invention has been made in order to solve the above-described problems, and a radiographic image capable of accurately confirming an imaging position without increasing the exposure amount when a plurality of radiographic images are continuously captured. An object is to provide a photographing apparatus.

In order to achieve the above object, a radiographic imaging apparatus according to a first aspect of the present invention captures a radiation image by detecting radiation that has been irradiated from the radiation irradiating means and transmitted through the subject. Each time the radiographic image is captured in the case where a plurality of radiographic images are captured by continuously detecting the radiation detected by the radiation detecting means and the radiation transmitted through the same subject by the radiation detecting means a plurality of times. A setting unit that sets at least one of a radiation direction of the radiation by the radiation irradiation unit, a position of the radiation irradiation unit, and an imaging condition; and a plurality of radiations that have passed through the same subject by the radiation detection unit. when capturing a plurality of radiation images are detected times according to the setting by the setting means, for each shooting of the radiation image, the radiation A changing unit that changes at least one of a radiation direction of the radiation by the projecting unit, a position of the radiation irradiating unit, and an imaging condition; and at least one of the plurality of radiographic images captured by the radiation detecting unit Display control means for controlling the image to be displayed on the display, storage means for storing the plurality of radiation images taken by the radiation detection means, and image composition means for combining the plurality of radiation images stored in the storage means It is comprised including.

According to the radiographic image capturing apparatus of the first invention, when the radiation detecting unit continuously detects the radiation transmitted through the same subject a plurality of times and captures a plurality of radiographic images, the changing unit sets the setting unit. In accordance with the setting, at least one of the irradiation direction of the radiation by the radiation irradiating means, the position of the radiation irradiating means, and the imaging conditions is changed for each radiographic image capturing. Further, radiation is emitted by the radiation irradiating means, and radiation detected by the radiation detecting means is transmitted from the radiation irradiating means and transmitted through the subject, and a radiation image is taken. Then, a plurality of radiation images photographed by the radiation detection means are stored in the storage means.

  Further, the display control unit controls the display device to display at least one of the plurality of radiographic images taken by the radiation detection unit.

  As described above, when radiographic images are captured a plurality of times in succession, by displaying at least one of the captured radiographic images on the display device, the imaging position can be accurately determined without increasing the exposure amount. Can be confirmed.

  The display control means according to the first invention can display on the display device a radiation image obtained by the first imaging by the radiation detection means. Thus, the shooting position can be confirmed at the initial stage of continuous shooting.

  The radiographic imaging device according to the first aspect of the present invention can further include an image synthesizing unit that synthesizes a plurality of radiographic images stored in the storage unit. As a result, when radiographic images are continuously captured a plurality of times to synthesize the radiographic images, the imaging position can be accurately confirmed without increasing the amount of exposure.

  The image composition means can generate a tomographic image from a plurality of radiation images. In addition, the image composition unit can compose a plurality of radiation images to generate a long image.

A radiographic image capturing apparatus according to a second aspect of the present invention includes a radiation irradiating unit that irradiates radiation, a radiation detecting unit that detects a radiation irradiated from the radiation irradiating unit and transmitted through a subject, and captures a radiographic image, and the radiation In the case where a plurality of radiation images are captured by continuously detecting the radiation that has passed through the region to be imaged of the subject by the detection means, and the plurality of radiation images are captured, the radiation is captured according to the input from the input means before capturing the radiation image. A changing unit that changes at least one of an irradiation direction of the radiation by the radiation irradiating unit, a position of the radiation irradiating unit, and an imaging condition so as to irradiate a portion of the subject to be imaged by the irradiating unit; Display for controlling to display at least one of the plurality of radiation images taken by the radiation detection means on a display device And control means is configured to include a storage means for storing the plurality of radiographic images captured, and the image combining means for combining said plurality of radiographic images stored in the storage means by said radiation detecting means .

According to the radiographic image capturing apparatus of the second invention, when the radiation detecting unit continuously detects the radiation transmitted through the region to be imaged of the subject a plurality of times and captures a plurality of radiographic images, the changing unit Before taking a radiographic image, in accordance with an input from the input means, the radiation irradiating means irradiates the object to be imaged with the radiation direction, the radiation irradiation direction by the radiation irradiating means, the position of the radiation irradiating means, and imaging Change at least one of the conditions. Then, radiation is emitted by the radiation irradiating means, and radiation detected from the radiation irradiating means and transmitted through the subject is detected by the radiation detecting means, and a radiation image is taken. Then, a plurality of radiation images photographed by the radiation detection means are stored in the storage means.

  Further, the display control unit controls the display device to display at least one of the plurality of radiographic images taken by the radiation detection unit.

  As described above, when radiographic images are captured a plurality of times in succession, by displaying at least one of the captured radiographic images on the display device, the imaging position can be accurately determined without increasing the exposure amount. Can be confirmed.

  According to the radiographic imaging device according to the present invention, when radiographic images are continuously captured a plurality of times, the exposure amount is increased by displaying at least one of the captured radiographic images on the display device. Therefore, there is an effect that the shooting position can be confirmed with high accuracy.

  Hereinafter, embodiments of the present invention will be described in detail. In the present embodiment, a case where the present invention is applied to a radiographic imaging system that performs tomosynthesis imaging will be described.

  As shown in FIG. 1, the radiographic imaging system 10 according to the first exemplary embodiment moves an X-ray (moving on a linear trajectory at the time of radiographic imaging and irradiates a subject. X-ray) and the like, and a radiation detection panel that is disposed at a distance from the radiation generation unit 12 and that detects radiation that has been irradiated from the radiation generation unit 12 and transmitted through the subject. 14.

  The radiation emitted from the radiation generation unit 12 is applied to the radiation detection panel 14 after passing through the subject positioned at the imaging position.

  The radiographic imaging system 10 corresponds to the radiographic imaging apparatus according to the present invention, the radiation generation unit 12 corresponds to the radiation irradiating means according to the present invention, and the radiation detection panel 14 corresponds to the radiation detecting means according to the present invention. It corresponds to.

  Here, tomosynthesis is a coined word of tomography (fault) and synthesis (integration, synthesis), and tomosynthesis function is a tomography of arbitrary height from a plurality of projection data obtained by one tomographic scan. This is a function for generating an image. A tomographic image obtained by mathematical reconstruction processing is a clear image unlike a conventional analog tomography (tomographic imaging with an analog film).

  The radiographic image capturing system 10 moves the radiation generating unit 12 along a linear trajectory at the time of capturing a radiographic image, and is irradiated from the radiation generating unit 12 in accordance with the movement of the linear trajectory of the radiation generating unit 12. The radiation detection panel 14 is moved so as to detect the radiation that has passed through the examiner, the imaging position moving unit 16 that changes the irradiation direction of the radiation generation unit 12, an input device such as a keyboard, and a pointing device such as a mouse The input / output device 18 composed of an input device and a display device, and a plurality of radiographic images are reconstructed to generate a plurality of tomographic images, and a tomographic image having an arbitrary height useful for diagnosis is selected. And controlling each of the image processing device 20 to be displayed on the input / output device 18, the radiation generation unit 12, the radiation detection panel 14, and the imaging position moving unit 16. With capturing a radiographic image, the radiographic image is displayed on the input and output device, and an imaging control unit 22 for transmitting a plurality of radiographic images to the image processing apparatus 20. The input / output device 18 is connected to a radiation information system (RIS), and the generated tomographic image having an arbitrary height is output from the input / output device 18 to the radiation information system.

  The photographing position moving unit 16 corresponds to the changing unit according to the present invention, the input / output device 18 corresponds to the display device according to the present invention, and the image processing device 20 corresponds to the image composition unit according to the present invention. ing.

  As shown in FIG. 3, the photographing control device 22 includes a CPU, a RAM, a ROM, an HDD that stores various programs and data including a program for executing a photographing processing routine described later, and various circuits. It is provided and functionally configured as follows. The imaging control device 22 includes a radiation generation control unit 26, an image reading unit 28, a control unit 30, an image storage unit 32, and a communication control unit 33.

  The radiation generation control unit 26 is connected to the radiation generation unit 12 and the control unit 30, and in accordance with an instruction from the control unit 30, the tube voltage, tube current, and radiation generation time when the radiation generation unit 12 generates the radiation. By controlling, the dose of radiation generated by the radiation generator 12 is controlled. The image reading unit 28 reads an image signal from the radiation detection panel 14 every time the subject is photographed and converts the image signal into digital image data. Various kinds of image data obtained by the conversion are also obtained. Perform image quality correction processing.

  The control unit 30 controls the imaging position moving unit 16 in accordance with an instruction input via the input / output device 18 to set the imaging position by the radiation generation unit 12 and the radiation detection panel 14, and the memory ( The imaging of the subject is controlled based on the imaging conditions stored in (not shown), and the radiographic image input from the image reading unit 28 is stored in the image storage unit 32.

  When the tomosynthesis imaging is performed, the control unit 30 continuously captures a plurality of radiation images by the radiation generation unit 12 and the radiation detection panel 14, and communicates the radiation image obtained by the first imaging input from the image reading unit 28. A plurality of radiation images transmitted to the input / output device 18 by the control unit 33 and stored in the image storage unit 32 are transmitted to the image processing device 20.

  As radiographing conditions, information such as the number of radiographic imaging in tomosynthesis radiography (for example, 50 to 90, which varies depending on the radiographic region), tube voltage, tube current, and irradiation time of the radiation generation unit 12 in radiography includes radiographic images. Each of the imaging regions of the subject that can be imaged by the imaging system 10 is stored in advance in the memory.

  The imaging position moving unit 16 includes an actuator or the like that can move the radiation generating unit 12 and the radiation detection panel 14, and images a region to be imaged (eg, chest, lumbar vertebra, limb bone, breast, etc.) of the subject. When notified from the control device 22, each of the radiation generating unit 12 and the radiation detection panel 14 is moved to a position for imaging the notified imaging part of the subject. Further, the imaging position moving unit 16 changes the irradiation direction of the radiation from the radiation generating unit 12 so as to image the notified imaging part of the subject according to the moving position of the radiation generating unit 12.

  Since the positions of the radiation generation unit 12 and the radiation detection panel 14 for imaging a certain imaging region of the subject also differ depending on the physique of the subject, the imaging position moving unit 16 includes an input / output device. When the adjustment of the imaging position is instructed via 18, the positions of the radiation generation unit 12 and the radiation detection panel 14 and the radiation irradiation direction of the radiation generation unit 12 are adjusted according to the instruction. .

  In addition, when performing tomosynthesis imaging, the imaging position moving unit 16 is controlled by the imaging control device 22 on a linear locus having a certain height from the detection surface of the radiation detection panel 14 for each radiographic image imaging. While changing the position of the radiation generation part 12 so that it may move, the irradiation direction of the radiation by the radiation generation part 12 is changed. Thereby, the position and irradiation direction of the radiation generation unit 12 are controlled so that a plurality of radiographic images are taken at different positions of the focal spot of the radiation generation unit 12 relative to the subject. Further, the imaging position moving unit 16 changes the position of the radiation detection panel 14 so as to move in parallel with the detection surface of the radiation detection panel 14 every time a radiographic image is captured, under the control of the imaging control device 22. In addition, the imaging position moving unit 16 is controlled by the imaging control device 22 so that the radiation detection panel 14 is positioned at a position where the radiation emitted from the radiation generation unit 12 and transmitted through the subject can be detected every time a radiographic image is captured. Change the position of.

  As will be described below, the image processing apparatus 20 reconstructs a plurality of radiation images by a conventionally known shift addition method. An appropriate amount of each radiographic image is shifted in the scanning direction with respect to a series of radiographic images taken while changing the incident angle from the radiation generating unit 12, and the shift results are overlapped to focus on a specific cut surface. A tomographic image is generated. Further, by adjusting the shift amount for each radiation image and arbitrarily changing the cut surface, a plurality of tomographic images for a plurality of cut surfaces are generated.

  Note that the reconstruction method is not limited to the shift addition method. For example, a reconstruction method of a plurality of radiographic images using the FBP method (Filtered Back Projection method), which is a typical method of the CT reconstruction method, is used. May be performed. The FBP method is a reconstruction method in which tomographic parallel plane tomographic scanning is regarded as a part of conbeam CT scanning and the filter back projection method is extended.

  Further, the image processing device 20 selects at least one tomographic image useful for diagnosis from a plurality of tomographic images obtained by reconstruction, and transmits the selected tomographic image to the input / output device 18.

  Next, configurations of the radiation detection panel 14 and the image reading unit 28 will be described. In the radiation detection panel 14, a photoelectric conversion layer (not shown) that absorbs radiation and changes into a charge is formed on the TFT active matrix substrate 34 shown in FIG. 4, and a bias connected to a high-voltage power source is further provided above the photoelectric conversion layer. An electrode (not shown) is formed and configured. The photoelectric conversion layer is made of amorphous a-Se (amorphous selenium) containing, for example, selenium as a main component (for example, a content rate of 50% or more), and when irradiated with radiation, the amount of charge corresponding to the amount of irradiated radiation. The generated radiation (electron-hole pair) is internally generated to convert the irradiated radiation into charges. Thereby, the image information carried by the irradiated radiation is converted into charge information.

  In addition, on the TFT active matrix substrate 34, a pixel unit 40 including a storage capacitor 36 for storing charges generated in the photoelectric conversion layer and a TFT 38 for reading out the charges stored in the storage capacitor 36 (note that FIG. 4, a plurality of bias electrodes and photoelectric conversion layers corresponding to the individual pixel portions 40 are schematically shown as photoelectric conversion portions 42), and are arranged in a matrix, and further along the direction of arrow A in FIG. 4. And a plurality of gate wirings 44 for turning on and off the TFTs 38 of the individual pixel portions 40, and the TFTs 38 extending and turned on along the arrow B direction perpendicular to the arrow A direction in FIG. A plurality of data wirings 46 for reading accumulated charges from the capacitor 36 are also provided.

  On the other hand, the image reading unit 28 includes a gate line driver 48 connected to each gate wiring 44 of the radiation detection panel 14. The gate line driver 48 is connected to the gate wiring 44 that has supplied the ON signal by supplying a high-level voltage signal (ON signal) to the specific gate wiring 44 at the time of reading the signal charges from the radiation detection panel 14. The TFT 38 of each pixel unit 40 is changed from OFF to ON, and after a certain period of time, the supply of the ON signal to the gate wiring 44 is stopped to connect to the gate wiring 44 that has supplied the ON signal. A gate line driving process for changing the TFT 38 of each pixel unit 40 from on to off is sequentially performed on the individual gate wirings 44.

  The image reading unit 28 includes the same number of operational amplifiers 50 as the number of data wirings 46 provided on the TFT active matrix substrate 34, and the individual data wirings 46 of the radiation detection panel 14 are inverting input terminals of different operational amplifiers 50. Is connected to each. Each operational amplifier 50 has a non-inverting input terminal connected to a GND wiring (ground wiring), one end of a capacitor 52 connected to the inverting input terminal, and the other end connected to an output terminal. . With the above configuration, each operational amplifier 50 and capacitor 52 functions as a charge amplifier that integrates a current (signal charge) flowing through the data wiring 46 connected to the inverting input terminal and outputs a signal having a level corresponding to the integration result. .

  The output terminal of each operational amplifier 50 (charge amplifier) is connected to one of a plurality of input terminals of a multiplexer (MUX) 54 via an amplifier and sample hold circuit (not shown), and the output of each charge amplifier. The signal is input to the MUX 54 in parallel. The output terminal of the MUX 54 is connected to the input terminal of the A / D converter 56, and the MUX 54 selects a plurality of input terminals in order, and the signal input via the selected input terminal is the A / D converter 56. Output to. As a result, parallel-serial conversion and A / D conversion (analog-digital conversion) are sequentially performed on a plurality of signals (the same number as the number of data wirings 46) input in parallel to the MUX 54.

  The output end of the A / D converter 56 is connected to the input end of the image quality correction processing unit 58, and the output end of the image quality correction processing unit 58 is connected to the input end of the control unit 30 (see FIG. 3). The image quality correction processing unit 58 performs offset correction, gain correction, defect correction, Log & Bit conversion, EDR (Exposure Data Recognizer: automatic density correction function) processing, MFP processing (Multi-multiple) as image quality correction processing for improving the image quality of an image. After performing objective frequency processing (multi-frequency processing) and gradation processing, data (image data) after image quality correction processing is output to the control unit 30.

  In addition, the image quality correction processing unit 58 performs image quality correction processing after performing offset correction, gain correction, Log & Bit conversion, pixel density conversion, and gradation processing as image quality correction processing for image data transmitted to the input / output device 18. The subsequent image data is output to the control unit 30. As described above, by simplifying the image quality correction processing for image data to be transmitted to the input / output device 18, it is possible to transmit the image data to the input / output device 18 at an early stage, and to display the image data on the input / output device 18 quickly. Can do.

  Next, the operation of the radiographic image capturing system 10 according to the first embodiment will be described. Hereinafter, a case where tomosynthesis imaging is performed will be described as an example.

  When the subject is located at the imaging position of the radiographic imaging system 10, the imaging processing routine shown in FIG.

  First, in step 100, it is determined whether or not an imaging region and imaging conditions are input from the input / output device 18 by the operator. At this time, the imaging region imaging condition setting screen is displayed on the display device of the input / output device 18, and the operator performs selection of the imaging region and change setting of imaging conditions corresponding to the imaging region such as the tube voltage of the radiation generator 12. Is called. When information indicating the imaging region and imaging conditions is input from the input / output device 18, the process proceeds to step 101.

  In step 101, the radiation position moving unit 16 moves each of the radiation generating unit 12 and the radiation detection panel 14 to an initial position in the case of performing tomosynthesis imaging of the set imaging region. In addition, the irradiation direction of the radiation generation unit 12 is changed so that the radiation is irradiated to the imaging region according to the position of the radiation generation unit 12.

  In step 102, it is determined from the input / output device 18 whether or not the shooting position has been adjusted. At this time, the photographing position adjustment screen is displayed on the display device of the input / output device 18, and the photographing position is adjusted by the operator. When the photographing position adjustment information is input from the input / output device 18, the process proceeds to step 104.

  In step 104, each of the radiation generation unit 12 and the radiation detection panel 14 is moved to the imaging position set to be adjusted by the imaging position moving unit 16. Further, the irradiation direction of the radiation generating unit 12 is changed so that the radiation is irradiated to the imaging region in accordance with the movement of the radiation generating unit 12.

  In the next step 106, it is determined whether or not a shooting start instruction is input from the input / output device 18. At this time, a shooting start instruction screen is displayed on the display device of the input / output device 18, and an instruction to start shooting is given by the operator. When the operator presses a button for instructing the start of shooting on the shooting start instruction screen and a shooting start instruction is input from the input / output device 18, the process proceeds to step 108.

  In step 108, an initial value 1 is set to a variable n indicating the number of imaging, and in step 110, a radiation image is captured by the radiation generation unit 12 and the radiation detection panel 14 based on the imaging conditions input in step 100. . In step 110 described above, the radiation generated by the radiation generator 12 is irradiated onto the imaging region of the subject located at the imaging position while controlling to match the tube voltage set in the imaging conditions. In addition, the radiation generator 12 generates radiation. Then, it passes through the imaging region and is incident on the radiation detection panel 14, and is stored as a charge in the storage capacitor 36 of each pixel unit 40 of the radiation detection panel 14, and a radiographic image is captured.

  In step 112, image information (signal charge) is read from the radiation detection panel 14 (the storage capacitor 36 of each pixel unit 40), and an image quality correction process is performed to obtain a radiation image. In the next step 114, the radiographic image acquired in step 112 is stored in the image storage unit 32 as a radiographic image of the n-th imaging.

  In step 116, it is determined whether or not the imaging in step 110 is the first imaging. If the imaging is the first imaging, in step 118, the radiation image obtained by the first imaging is input / output. The data is transmitted to the device 18, and the process proceeds to Step 120.

  At this time, in the input / output device 18, the radiation image obtained by the first imaging transmitted from the imaging control device 22 is displayed on the display device. As a result, the operator can check the shooting position and shooting conditions. When the shooting position and shooting conditions are incorrect, the operator can instruct the imaging stop by the input / output device 18, and when the imaging stop instruction is input from the input / output device 18 to the imaging control device 22, the imaging is performed. The control device 22 stops tomosynthesis imaging and ends the imaging processing routine.

  If it is determined in step 116 that the second and subsequent shootings are made, the process proceeds to step 120.

  In step 120, it is determined whether or not the number of times of shooting n is less than the number of times of shooting set in the shooting conditions. If the number of times of shooting n has not reached the number of times of shooting set in the shooting conditions, step 122 is performed. Then, n is incremented. In step 124, the imaging position moving unit 16 moves each of the radiation generation unit 12 and the radiation detection panel 14 to a position corresponding to the next imaging, and at the imaging site according to the position of the radiation generation unit 12. The irradiation direction of the radiation generation unit 12 is changed so that the radiation is irradiated, and the process returns to Step 110.

  If it is determined in step 120 that radiographic images have been taken for the number of times set in the radiographing conditions, in step 126 all the radiographic images stored in the image storage unit 32 are processed by the image processing apparatus. 20 to finish the photographing processing routine.

  When the imaging processing routine is executed as described above, the radiation direction of the radiation generation unit 12 and the position of the radiation generation unit 12 are changed and the position of the radiation detection panel 14 is changed every time a radiographic image is captured. On the other hand, the radiation detection panel 14 continuously detects the radiation transmitted through the same subject a plurality of times, captures a plurality of radiation images, and performs tomosynthesis imaging.

  Then, the image processing device 20 combines and reconstructs all the radiographic images transmitted from the imaging control device 22, and generates a plurality of tomographic images for a plurality of cut surfaces. In the image processing device 20, at least one tomographic image useful for diagnosis is selected from the plurality of generated tomographic images, and the selected tomographic image is transmitted to the input / output device 18.

  In the input / output device 18, the tomographic image transmitted from the image processing device 20 is displayed on the display device, and the tomographic image is confirmed by the operator.

  As described above, according to the radiographic image capturing system according to the first embodiment, when tomosynthesis imaging is performed by continuously capturing radiographic images a plurality of times, the first radiographic image is input. By displaying on the display device of the output device, the operator can check the shooting position and shooting conditions with high accuracy without increasing the amount of exposure.

  Also, when the first radiographic image is captured, the first radiographic image is displayed on the display device, so that the operator confirms the imaging position and imaging conditions at the initial stage of continuous imaging in tomosynthesis imaging. Can be made.

  In the above embodiment, the case where the radiographic image obtained by the first imaging is displayed on the display device has been described as an example. However, the present invention is not limited to this, and can be obtained by the second and subsequent imaging. The radiographic image may be displayed on the display device so that the operator can confirm the imaging position and imaging conditions. Further, two or more radiation images may be displayed on the display device so that the operator can confirm the imaging position and imaging conditions.

  Next, a second embodiment will be described. In the second embodiment, a case where the present invention is applied to a radiation imaging system that captures an energy subtraction image will be described as an example. Since the radiation imaging system according to the second embodiment has the same configuration as that of the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the second embodiment, a point where a plurality of radiation images are captured without changing the positions of the radiation generator and the radiation detection panel, and an energy subtraction image is generated from the plurality of radiation images. This is mainly different from the first embodiment.

  In capturing an energy subtraction image, in capturing a radiation image by the radiation generator 12 and the radiation detection panel 14, the same part of the subject is photographed with different tube voltages, and the image processing device 20 performs each tube voltage at each tube voltage. By weighting the radiation image obtained by imaging and calculating the difference, one of the image part corresponding to the hard tissue such as the bone part and the image part corresponding to the soft tissue in the image is emphasized and the other is The removed image is generated as an energy subtraction image.

  The imaging position moving unit 16 of the radiographic image capturing system according to the second embodiment moves the position of the radiation generating unit 12 so as to irradiate the imaging region with radiation before imaging the radiographic image, and generates radiation. The irradiation direction of the unit 12 is changed. Further, the radiation detection panel 14 is moved so as to detect the radiation irradiated from the radiation generation unit 12 and transmitted through the subject according to the position and irradiation direction of the radiation generation unit 12.

  When capturing the energy subtraction image, the control unit 30 continuously captures a plurality of radiation images of the imaging region using the radiation generation unit 12 and the radiation detection panel 14, and inputs the diagnostic image from the image reading unit 28. Is transmitted to the input / output device 18 by the communication control unit 33, and a plurality of radiation images stored in the image storage unit 32 are transmitted to the image processing device 20.

  In addition, as imaging conditions, imaging time intervals in multiple (for example, two) imaging for generating an energy subtraction image, tube voltage of the radiation generation unit 12 in each imaging, tube current, irradiation time, and any number of times Such information as whether to output the image as a diagnostic image is stored in advance in a memory (not shown) for each imaging region of the subject that can be imaged by the radiographic imaging system. For example, when the imaging region is the chest, the tube voltage of the radiation generating unit 12 in the first imaging is low, the tube voltage of the radiation generating unit 12 in the second imaging is high, and the second imaging. It is stored as an imaging condition to output a radiographic image obtained as described above as a diagnostic image. When the imaging region is the lumbar spine, the tube voltage of the radiation generator 12 in the first imaging is low, the tube voltage of the radiation generator 12 in the second imaging is high, and the first imaging. It is stored as an imaging condition to output a radiographic image obtained as described above as a diagnostic image.

  The image processing apparatus 20 calculates a difference by assigning a predetermined weight different from each other to each of the radiographic image obtained by the first imaging and the radiographic image obtained by the second imaging, thereby obtaining energy subtraction. An image is generated, and the generated energy subtraction image is displayed on the input / output device 18.

  Next, an imaging processing routine according to the second embodiment will be described with reference to FIG. Note that the same processes as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  First, in step 100, it is determined whether or not an imaging region and imaging conditions are input by the operator from the input / output device 18. When information indicating the imaging region and imaging conditions is input from the input / output device 18, the step is performed. Go to 252.

  In step 252, each of the radiation generation unit 12 and the radiation detection panel 14 is moved by the imaging position moving unit 16 to a position for imaging the set imaging region. In addition, the irradiation direction of the radiation generation unit 12 is changed by the imaging position moving unit 16 so that radiation is applied to the imaging region.

  In step 102, it is determined whether or not the shooting position has been adjusted from the input / output device 18. When the shooting position adjustment information is input from the input / output device 18, the process proceeds to step 104. In Step 104, the radiation generation unit 12 and the radiation detection panel 14 are moved to the imaging position set to be adjusted by the imaging position moving unit 16, and the radiation generation unit 12 is moved according to the movement of the radiation generation unit 12. Change the irradiation direction.

  In the next step 106, it is determined whether or not a shooting start instruction is input from the input / output device 18. When a shooting start instruction is input from the input / output device 18, the process proceeds to step 108. In step 108, an initial value 1 is set to a variable n indicating the number of imaging, and in step 254, a radiation image is captured by the radiation generation unit 12 and the radiation detection panel 14 based on the imaging condition input in step 100. . In step 254, the radiation generated by the radiation generating unit 12 is controlled to match the tube voltage of the n-th imaging set in the imaging conditions, and the imaging region of the subject located at the imaging position The radiation generator 12 generates radiation so as to be irradiated. Then, it passes through the imaging region and enters the radiation detection panel 14, and is stored as a charge in the storage capacitor 36 of each pixel unit 40 of the radiation detection panel 14, and a radiographic image is captured.

  In step 112, image information (signal charge) is read from the radiation detection panel 14 (the storage capacitor 36 of each pixel unit 40), and an image quality correction process is performed to obtain a radiation image. In the next step 114, the radiographic image acquired in step 112 is stored in the image storage unit 32 as a radiographic image of the n-th imaging.

  In step 256, based on the set imaging conditions, it is determined whether or not the radiographic image obtained by the n-th imaging in step 254 is a diagnostic image, and the radiographic image obtained by the n-th imaging is used as a diagnostic image. In this case, in step 258, the radiation image obtained by the n-th imaging is transmitted to the input / output device 18, and the process proceeds to step 120.

  At this time, in the input / output device 18, a radiation image as a diagnostic image obtained by the n-th imaging transmitted from the imaging control device 22 is displayed on the display device. As a result, the operator can check the shooting position and shooting conditions. When the shooting position and shooting conditions are incorrect, the operator can instruct the imaging stop by the input / output device 18, and when the imaging stop instruction is input from the input / output device 18 to the imaging control device 22, the imaging is performed. The control device 22 stops shooting the energy subtraction image and ends the shooting processing routine.

  If it is determined in step 256 that the radiographic image obtained by the n-th imaging is not a diagnostic image, the process proceeds to step 120.

  In step 120, it is determined whether or not the number of times of photographing n is less than the number of times of photographing set in the photographing conditions (for example, two times), and the number of times of photographing n has not reached the number of times of photographing set in the photographing conditions. In step 122, n is incremented, and the process returns to step 254.

  If it is determined in step 120 that radiographic images have been taken for the number of times set in the radiographing conditions, in step 126 all the radiographic images stored in the image storage unit 32 are processed by the image processing apparatus. 20 to finish the photographing processing routine.

  When the imaging processing routine is executed as described above, the radiation generation direction of the radiation generation unit 12 and the position of the radiation generation unit 12 are changed so that the radiation is irradiated onto the imaging region before the radiographic image is acquired. At the same time, after changing the position of the radiation detection panel 14, the radiation is irradiated with different tube voltages of the radiation generation unit 12, and the radiation that has passed through the same subject is continuously detected multiple times by the radiation detection panel 14. Thus, a plurality of radiation images are taken.

  In the image processing device 20, all the radiation images transmitted from the imaging control device 22 are combined to generate an energy subtraction image, and the generated energy subtraction image is transmitted to the input / output device 18.

  In the input / output device 18, the energy subtraction image transmitted from the image processing device 20 is displayed on the display device, and the energy subtraction image is confirmed by the operator.

  As described above, according to the radiographic image capturing system according to the second embodiment, when a radiographic image is continuously captured and an energy subtraction image is captured, the radiographic image is captured as a diagnostic image. By displaying the radiation image on the display device of the input / output device, it is possible to allow the operator to check the imaging position and imaging conditions with high accuracy without increasing the exposure dose.

  In the above-described embodiment, the case where an energy subtraction image is generated by capturing radiographic images twice in succession has been described as an example. However, the present invention is not limited to this. Then, the radiographic image may be taken three times, and an energy subtraction image may be generated from the obtained three radiographic images.

  Next, a third embodiment will be described. In the third embodiment, a case where the present invention is applied to a radiation imaging system that captures a long image will be described as an example. Since the radiation imaging system according to the third embodiment has the same configuration as that of the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the third embodiment, a long image is generated from a point where the whole body of the subject is imaged and a plurality of radiation images while changing the positions of the radiation generation unit and the radiation detection panel. This is mainly different from the first embodiment.

  When photographing a long image, the photographing position moving unit 16 of the radiation image photographing system according to the third embodiment detects the radiation detection panel 14 every time a radiation image is photographed under the control of the photographing control device 22. The position of the radiation generator 12 is changed so as to move on a linear locus having a certain height from the surface. The imaging position moving unit 16 moves in parallel with the detection surface of the radiation detection panel 14 in accordance with the change in the position of the radiation generating unit 12 every time a radiographic image is captured, under the control of the imaging control device 22. Thus, the position of the radiation detection panel 14 is changed. Thereby, the imaging position moving unit 16 changes the position of the radiation detection panel 14 to a position where the radiation emitted from the radiation generation unit 12 and transmitted through the subject can be detected every time the radiographic image is captured.

  When capturing a long image, the control unit 30 changes the positions of the radiation generation unit 12 and the radiation detection panel 14 by the imaging position moving unit 16 every time a radiographic image is captured. And each part of the whole body of the subject is continuously photographed by the radiation detection panel 14. In addition, the control unit 30 transmits the radiation image obtained by the first imaging input from the image reading unit 28 to the input / output device 18 by the communication control unit 33, and images a plurality of radiation images stored in the image storage unit 32. Transmit to the processing device 20.

  As imaging conditions, information such as the number of times of imaging for generating a long image (for example, 2 to 5 times), the tube voltage of the radiation generator 12 at the time of imaging, the tube current, and the irradiation time are stored in a memory (not shown). Stored in advance.

  The image processing device 20 combines a plurality of radiation images to generate a long image representing the whole body of the subject, and causes the input / output device 18 to display the generated long image.

  In the imaging processing routine according to the third embodiment, first, it is determined from the input / output device 18 whether or not imaging conditions are input by the operator, and information indicating the imaging conditions is input from the input / output device 18. Then, the radiation position moving unit 16 moves the radiation generating unit 12 and the radiation detection panel 14 to an initial position when a long image is captured.

  Then, it is determined whether or not the shooting position has been adjusted from the input / output device 18, and when the shooting position adjustment information is input from the input / output device 18, the shooting position set to be adjusted by the shooting position moving unit 16. Each of the radiation generator 12 and the radiation detection panel 14 is moved to a position.

  Then, it is determined whether or not a shooting start instruction is input from the input / output device 18, and when a shooting start instruction is input from the input / output device 18, an initial value 1 is set to the variable n indicating the number of shootings and input. Based on the obtained imaging conditions, a radiation image is captured by the radiation generation unit 12 and the radiation detection panel 14. Next, image information from the radiation detection panel 14 is read out, image quality correction processing is performed, a radiation image is acquired, and the acquired radiation image is stored in the image storage unit 32 as a radiation image of the n-th imaging.

  Then, it is determined whether or not the latest imaging is the first imaging, and if it is the first imaging, a radiographic image obtained by the first imaging is transmitted to the input / output device 18. At this time, in the input / output device 18, a radiographic image obtained by the first imaging transmitted from the imaging control device 22 is displayed on the display device, and the operator confirms the imaging position and imaging conditions. On the other hand, if it is determined that the most recent shooting is the second or later shooting, it is determined whether or not the shooting count n is less than the shooting count set in the shooting conditions. If the set number of shootings has not been reached, the number of shootings n is incremented. Then, each of the radiation generation unit 12 and the radiation detection panel 14 is moved to a position corresponding to the next imaging by the imaging position moving unit 16, and radiographic images are captured again.

  On the other hand, when radiographic images are taken for the number of times set in the radiographing conditions, all radiographic images stored in the image storage unit 32 are transmitted to the image processing device 20 and the radiographing processing routine is executed. finish.

  When the imaging processing routine is executed as described above, the radiation detection panel 14 transmits the same subject while changing the position of the radiation generation unit 12 and the position of the radiation detection panel 14 every time a radiographic image is captured. The detected radiation is detected a plurality of times in succession, and a plurality of radiation images are taken.

  In the image processing device 20, all the radiographic images transmitted from the imaging control device 22 are combined to generate a long image representing the whole body of the subject, and the generated long image is the input / output device 18. Sent to.

  In the input / output device 18, the long image transmitted from the image processing device 20 is displayed on the display device, and the long image is confirmed by the operator.

  As described above, according to the radiographic image capturing system according to the third embodiment, when a radiographic image is continuously captured and a long image is captured, the radiation captured first time By displaying the image on the display device of the input / output device, the operator can check the shooting position and shooting conditions with high accuracy without increasing the exposure amount.

  In addition, when the first radiographic image is captured, the first radiographic image is displayed on the display device, so that the operator can determine the imaging position and the imaging at the initial stage of continuous imaging in the imaging of the long image. The condition can be confirmed.

  In the above-described embodiment, the case where the radiation image obtained by the first imaging is displayed on the display device has been described as an example. The radiographic image may be displayed on the display device so that the operator can confirm the imaging position and imaging conditions. Further, two or more radiation images may be displayed on the display device so that the operator can confirm the imaging position and imaging conditions.

  In addition, in the first to third embodiments, the imaging control device may perform another imaging or different imaging of the same subject while the image processing device synthesizes a plurality of radiation images. You may control to image | photograph the subject. As a result, it is possible to perform tomosynthesis imaging, energy subtraction image imaging, and long image imaging without significantly reducing imaging processing throughput.

It is the schematic which shows the radiation generation part and radiation detection panel of the radiographic imaging system which concern on the 1st Embodiment of this invention. It is a block diagram which shows schematic structure of the radiographic imaging system which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the structure of the imaging | photography control apparatus of the radiographic imaging system which concerns on the 1st Embodiment of this invention. It is a schematic block diagram of the radiation detection panel and image reading part of the radiographic imaging system which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the content of the imaging | photography process routine in the imaging | photography control apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the content of the imaging | photography process routine in the imaging | photography control apparatus which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Radiation imaging system 12 Radiation generation part 14 Radiation detection panel 16 Imaging position moving part 18 Input / output device 20 Image processing apparatus 22 Imaging control apparatus 26 Radiation generation control part 28 Image reading part 30 Control part 32 Image storage part 33 Communication control part 34 Active matrix substrate

Claims (5)

Radiation irradiating means for irradiating radiation;
Radiation detecting means for capturing radiation images by detecting radiation irradiated from the radiation irradiating means and transmitted through the subject; and
The radiation irradiating means for each radiographic image capturing in the case where a plurality of radiographic images are acquired by continuously detecting the radiation transmitted through the same subject by the radiation detecting means and input a plurality of times. Setting means for setting at least one of the radiation direction of radiation, the position of the radiation irradiation means, and imaging conditions;
When the radiation detecting means continuously detects the radiation transmitted through the same subject a plurality of times and captures a plurality of radiation images, according to the setting by the setting means , the radiation irradiation means Changing means for changing at least one of the radiation direction of radiation, the position of the radiation irradiation means, and the imaging conditions;
Display control means for controlling the display device to display at least one of the plurality of radiation images photographed by the radiation detection means;
Storage means for storing the plurality of radiation images photographed by the radiation detection means;
Image combining means for combining the plurality of radiation images stored in the storage means;
A radiographic imaging apparatus including:   The radiographic image capturing apparatus according to claim 1, wherein the display control unit displays the radiographic image obtained by the first imaging by the radiation detecting unit on the display device. The image synthesizing means, a radiographic imaging apparatus according to claim 1 or 2, wherein generating a tomographic image from the plurality of radiographic images. The image synthesizing means synthesizes the plurality of radiographic images, radiographic imaging apparatus according to claim 1 or 2, wherein generating a long image. Radiation irradiating means for irradiating radiation;
Radiation detecting means for capturing radiation images by detecting radiation irradiated from the radiation irradiating means and transmitted through the subject; and
When capturing a plurality of radiation images by continuously detecting the radiation transmitted through the region to be imaged of the subject by the radiation detection unit, before capturing the radiation image, according to the input from the input unit, Changing means for changing at least one of the irradiation direction of the radiation by the radiation irradiating means, the position of the radiation irradiating means, and the imaging conditions so that the radiation irradiating means irradiates the portion of the subject to be imaged; ,
Display control means for controlling the display device to display at least one of the plurality of radiation images photographed by the radiation detection means;
Storage means for storing the plurality of radiation images photographed by the radiation detection means;
Image combining means for combining the plurality of radiation images stored in the storage means;
A radiographic imaging apparatus including:

Images