Patent Publication Number: US-2018049713-A1

Title: Control apparatus, control system, processing method, and non-transitory computer-readable storage medium

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a control apparatus, a control system, and a processing method. 
     Description of the Related Art 
     In a medical institution, a medical information system by network connection is constructed. For example, if it is determined that radiation imaging is necessary, an examination instruction is input from an HIS (Hospital Information System) terminal or an RIS (Radiology Information System) terminal and transmitted to a radiography department that is the request destination. These network communications are implemented by a technical framework based on a medical standard specification guideline called IHE (Integrating the Healthcare Enterprise). 
     Request information transmitted by the HIS or RIS is called an examination order. The examination order includes a request source department name, an examination item, the personal data of a patient, and the like. When the radiography department receives the examination order, an imaging protocol necessary for imaging is input to a radiation imaging system. Then, the examination progresses based on the examination order including a plurality of imaging protocols. Here, an imaging protocol includes an imaging part and an imaging method requested by a doctor, information of image processing, and the like. An image obtained by imaging is stored in association with imaging information such as an imaging date/time and an exposure dose. During the examination, a captured image unsuitable for a diagnosis is sometimes obtained due to a failure of an imaging technique by an imaging technician. In this case, a rejected image instruction is input to the radiation imaging system, thereby storing the captured image as a rejected image. At the end of the examination, captured images are transferred to a medical image management system called a PACS (Picture Archiving and Communication Systems) and saved. 
     Japanese Patent Laid-Open No. 2001-175771 discloses a technique of controlling to transfer only effective images to the PACS and not to transfer rejected images to the PACS because transfer of the rejected images to the PACS increases the network load and causes a squeeze on the capacity of the PACS. 
     Japanese Patent Laid-Open No. 2007-44272 discloses a technique of automatically acquiring and managing rejected images and the imaging information of the rejected images, for the purpose of improving the skill of an imaging technician and reducing ineffective exposure of a patient along with the skill improvement. This makes it possible to transfer all pieces of information about rejected images to a rejected image statistic server. 
     In the medical field, the imaging technician may generate a number of images until images suitable for a diagnosis, for example, a projected image obtained by tomosynthesis imaging and a reconstructed image based on the projected image, or a captured image and a replicated image based on the captured image are obtained. 
     However, images that are handled as rejected images not to transfer images other than images suitable for a diagnosis to the PACS may include images that are not images of an imaging failure. The images handled as rejected images are transferred to the rejected image statistic server. In this case, even the images that are not images of an imaging failure and are originally not necessary for rejected image analysis are transferred to the rejected image statistic server. This requires time to select images necessary for rejected image analysis and lowers the efficiency of rejected image analysis. 
     The present invention has been made in consideration of the above-described problems, and provides a technique of reducing the time to select images necessary for rejected image analysis and improving the efficiency of rejected image analysis. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, there is provided a control apparatus comprising: an instruction unit configured to receive an instruction to change one of a captured image and an image that is a processed image based on the captured image to a rejected image; and an assigning unit configured to assign information representing an imaging success/failure to the image based on information of an imaging protocol of the image and information representing whether the image is the rejected image instructed by the instruction unit. 
     According to one aspect of the present invention, there is provided a control apparatus comprising: an instruction unit configured to receive an instruction to change an image to a rejected image; a determination unit configured to determine whether to output the rejected image to a rejected image statistic terminal; and an output unit configured to output the rejected image determined, by the determination unit, to be output to the rejected image statistic terminal. 
     According to one aspect of the present invention, there is provided a control system comprising: an instruction unit configured to receive an instruction to change one of a captured image and an image that is a processed image based on the captured image to a rejected image; and an assigning unit configured to assign information representing an imaging success/failure to the image based on information of an imaging protocol of the image and information representing whether the image is the rejected image instructed by the instruction unit. 
     According to one aspect of the present invention, there is provided a processing method executed by a control apparatus, comprising: receiving an instruction to change one of a captured image and an image that is a processed image based on the captured image to a rejected image; and assigning information representing an imaging success/failure to the image based on information of an imaging protocol of the image and information representing whether the image is the rejected image instructed in the receiving the instruction. 
     According to one aspect of the present invention, there is provided a processing method executed by a control apparatus, comprising: receiving an instruction to change an image to a rejected image; determining whether to output the rejected image to a rejected image statistic terminal; and outputting the rejected image determined, in the determining whether to output the rejected image, to be output to the rejected image statistic terminal. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram showing an example of the arrangement of a control system according to the first to fourth embodiments; 
         FIG. 2  is a block diagram showing an example of the functional arrangement of an X-ray imaging control unit according to the first and third embodiments; 
         FIG. 3  is a view showing an example of an imaging screen according to the first, third, and fifth embodiments; 
         FIG. 4  is a flowchart showing an example of the imaging operation of an X-ray imaging system according to the first to sixth embodiments; 
         FIG. 5  is a flowchart showing an example of imaging processing and post-processing according to the first, third, and fifth embodiments; 
         FIG. 6  is a table showing an example of examination information according to the first, third, and fifth embodiments; 
         FIG. 7  is a flowchart showing an example of the operation of an imaging success/failure identification unit according to the first, third, and fifth embodiments; 
         FIG. 8  is a flowchart showing an example of the operation of a rejected image statistic output unit according to the first and second embodiments; 
         FIG. 9  is a block diagram showing an example of the functional arrangement of an X-ray imaging control unit according to the second and fourth embodiments; 
         FIG. 10  is a view showing an example of an imaging screen according to the second, fourth, and sixth embodiments; 
         FIG. 11  is a flowchart showing an example of imaging processing and post-processing according to the second, fourth, and sixth embodiments; 
         FIG. 12  is a table showing an example of examination information according to the second, fourth, and sixth embodiments; 
         FIG. 13  is a flowchart showing an example of the operation of an imaging success/failure identification unit according to the second, fourth, and sixth embodiments; 
         FIG. 14  is a flowchart showing an example of the operation of a rejected image statistic output unit according to the third to sixth embodiments; 
         FIG. 15  is a block diagram showing an example of the arrangement of a control system according to the fifth and sixth embodiments; 
         FIG. 16  is a block diagram showing an example of the functional arrangement of an X-ray imaging control unit according to the fifth embodiment; and 
         FIG. 17  is a block diagram showing an example of the functional arrangement of an X-ray imaging control unit according to the sixth embodiment. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     An exemplary embodiment(s) of the present invention will now be described in detail with reference to the drawings. It should be noted that the relative arrangement of the components, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. 
     In the embodiments to be described below, an example in which X-rays are applied as radiation will be described. However, the radiation is not limited to X-rays and may be, for example, an electromagnetic wave, α-rays, β-rays, or γ-rays. Note that arrangements to be described in the following embodiments are merely examples, and the present invention is not limited to the illustrated arrangements. 
     First Embodiment 
     &lt;Outline&gt; 
     In the first embodiment, an example will be described in which an instruction to handle a captured image or an image that is a processed image based on the captured image as a rejected image is received, and information representing an imaging success/failure is assigned to the image based on the information of the imaging protocol of the image and information representing whether the image is the instructed rejected image. More specifically, if a projected image captured using a tomosynthesis imaging protocol and reconstructed images generated from the projected image include an effective image (an image that is not rejected image-instructed), information representing an imaging success is assigned to all images. 
     If the projected image and the reconstructed images include an effective image, it is considered that images other than the specific effective image should not be output to a rejected image statistic terminal (rejected image statistic server), and therefore, a rejected image instruction is done for the other images (although they are not images of an imaging failure). For this reason, if an effective image is included, information representing an imaging success is assigned to all images. This can prevent an image that is rejected image-instructed but is not an image of an imaging failure from being output to the rejected image statistic terminal. 
     On the other hand, if no effective image is included, information representing an imaging failure is assigned to all images. Then, each image with the assigned information representing an imaging failure and the additional information (including at least one piece of information of a protocol number, an imaging protocol, a re-imaging source protocol number, an image number, an image type, information representing a rejected image state, and information representing an imaging success/failure) of the image are output to the rejected image statistic terminal. An image that has failed in imaging can thus be output to the rejected image statistic terminal. 
     In this way, when the information representing the imaging success/failure is assigned separately from the information representing the rejected image state, an image that has failed in imaging and is needed for rejected image analysis can be output. Hence, the efficiency of rejected image analysis can be improved. The first embodiment will be described below in detail. 
     &lt;Arrangement of Control System&gt; 
       FIG. 1  is a block diagram showing an example of the arrangement of a control system according to an embodiment. A control system  1  includes an X-ray imaging system  10 , an RIS terminal  20 , a PACS terminal  30 , and a rejected image statistic terminal  40 . These devices are connected via, for example, a communication unit  50  such as a network. 
     The X-ray imaging system  10  captures an X-ray digital image (to be referred to as a captured image hereinafter). The RIS terminal  20  is an information system in a radiography department. The PACS terminal  30  saves and manages the image captured by the X-ray imaging system  10 . The rejected image statistic terminal  40  saves and manages images that have failed in imaging. Note that the rejected image statistic terminal  40  need not always be separated from the X-ray imaging system  10 , as shown in  FIG. 1 , and may exist in the X-ray imaging system  10 . The rejected image statistic terminal  40  may be provided in a control apparatus  101  to be described later. Alternatively, the rejected image statistic terminal  40  may be integrated with the RIS terminal  20  and/or the PACS terminal  30 . 
     The X-ray imaging system  10  executes an examination (imaging) based on an examination order formed from a plurality of imaging protocols. Each of the imaging protocols defines imaging conditions, the contents of image processing to be executed for a captured image, and the like. More specifically, each imaging protocol includes various kinds of parameter information such as an imaging time and image processing and imaging execution information. In addition, imaging environment information (a sensor type and an imaging posture) is associated with the imaging protocol. 
     &lt;Arrangement of X-Ray Imaging System&gt; 
     The X-ray imaging system  10  includes the control apparatus  101 , an imaging unit  102 , a display unit  103 , and an operation unit  104 . 
     The control apparatus  101  includes an X-ray generation control unit  1011  and an X-ray imaging control unit  1012 . The X-ray generation control unit  1011  controls generation of X-rays from an X-ray tube  1021 . More specifically, the X-ray generation control unit  1011  applies a voltage to the X-ray tube  1021  based on imaging conditions (for example, parameters such as a tube current, a tube voltage, and an irradiation time) corresponding to an imaging protocol to cause the X-ray tube  1021  to generate X-rays. The X-ray imaging control unit  1012  generally controls X-ray imaging processing by a sensor  1022  based on the imaging protocol. The X-ray imaging control unit  1012  also performs, for example, image processing (for example, correction processing, tone processing, or frequency processing) for a captured image. The image processing is performed using image processing parameters corresponding to the imaging protocol at the time of imaging. 
     The imaging unit  102  includes the X-ray tube  1021  and the sensor  1022 . The X-ray tube  1021  functions as a radiation generator and irradiates an object (that is, a subject) with X-rays. The sensor  1022  is an FPD (Flat Panel Detector) functioning as a radiation detector and detects the X-rays transmitted through the subject. The sensor  1022  A/D-converts charges corresponding to the detected amount of X-rays transmitted through the subject and transfers the data to the X-ray imaging control unit  1012  as a captured image. 
     The display unit  103  is formed from, for example, a display and displays a system state and the like to the operator. The display unit  103  displays, for example, an examination order received from the RIS terminal  20  (or an examination order created by the operator). The operation unit  104  is formed from, for example, a keyboard, a mouse, and various kinds of buttons, and inputs an instruction from the operator to the apparatus. The operator inputs, for example, an image replication instruction by operating the operation unit  104 . 
     &lt;Arrangement of X-Ray Imaging Control Unit&gt; 
       FIG. 2  is a block diagram showing an example of the arrangement of the X-ray imaging control unit according to an embodiment. The X-ray imaging control unit  1012  includes an examination order input unit  201 , an image input unit  202 , an examination information storage unit  203 , an image processing unit  204 , and a rejected image instruction unit  205 . The X-ray imaging control unit  1012  also includes a re-imaging instruction unit  206 , an examination information output unit  207 , a rejected image statistic output unit  208 , and an imaging success/failure identification unit  209 . 
     The examination order input unit  201  inputs an examination order. The examination order is examination information including the information of a patient to be captured and imaging contents. The examination order is acquired from an external system such as the RIS terminal  20  or input via an operation on the operation unit  104 . The image input unit  202  inputs a radiation image captured by the X-ray imaging system  10 . The radiation image is input via a network or input via a medium such as a CD-ROM or a DVD in some cases. 
     The examination information storage unit  203  stores the image input from the image input unit  202  and the examination information input from the examination order input unit  201  in association with each other. The image processing unit  204  performs image processing such as correction processing, tone processing, or frequency processing for the captured image using image processing parameters corresponding to the imaging protocol. 
     The rejected image instruction unit  205  assigns information representing a rejected image state to the captured image as additional information, and changes the captured image to a rejected image. The rejected image instruction unit  205  stores the change contents in the examination information storage unit  203 . The re-imaging instruction unit  206  prepares for re-imaging concerning an executed imaging protocol. More specifically, the re-imaging instruction unit  206  changes a captured image of a designated executed imaging protocol to a rejected image by controlling the rejected image instruction unit  205 . Additionally, the re-imaging instruction unit  206  adds the same imaging protocol as the executed imaging protocol to the examination by controlling the examination order input unit  201  such that the same imaging can be performed. 
     The examination information output unit  207  outputs examination information stored in the examination information storage unit  203  to the PACS terminal  30 . The rejected image statistic output unit  208  outputs, of the information stored in the examination information storage unit  203 , a captured image and additional information thereof to the rejected image statistic terminal  40 . The imaging success/failure identification unit  209  identifies, based on the examination information and the additional information of the captured image stored in the examination information storage unit  203 , whether the imaging has succeeded or failed concerning the captured image. 
     &lt;Example of Imaging Screen&gt; 
       FIG. 3  shows an example of an imaging screen according to an embodiment of the present invention. An imaging screen  301  includes a preview image display region  302  that displays a preview of a captured image, and a sensor state display region  303  that displays the state of the sensor  1022  concerning an imaging protocol under execution. The imaging screen  301  also includes a patient information display region  304 , an examination order display region  305 , a rejected image button  312  that instructs change of a captured image to a rejected image state, a re-imaging button  313  that instructs re-imaging, and an examination end button  314  that instructs termination of examination. 
     The examination order display region  305  displays imaging protocols  306  and  310  included in an examination. The name of an imaging technique is displayed in correspondence with each imaging protocol. The imaging protocols are provided with thumbnail display regions  308 ,  311 ,  315 , and  316  that display the thumbnails of images captured and generated by the imaging protocols. A symbol  309  representing a rejected image is displayed on the thumbnail of a rejected image. The imaging protocol  306  is a tomosynthesis imaging protocol, and a reconstruction button  307  that instructs reconstructed image generation is displayed. 
     &lt;Processing&gt; 
     The procedure of a series of processes from the start to the end of an examination executed by the control apparatus  101  according to an embodiment of the present invention will be described next with reference to the flowchart of  FIG. 4 . 
     In step S 401 , the control apparatus  101  acquires an examination order from the RIS terminal  20  (or an examination order manually created by the operator) via the examination order input unit  201 , and stores examination information included in the acquired examination order in the examination information storage unit  203 . 
     In step S 402 , the control apparatus  101  starts an examination and displays the imaging screen  301  on the display unit  103 . 
     In step S 403 , the control apparatus  101  executes imaging processing and post-processing for the captured image. Details of the processing of step S 403  will be described here with reference to the flowchart of  FIG. 5 . 
     In step S 501 , the control apparatus  101  makes preparations for imaging. More specifically, the control apparatus  101  changes an unexecuted imaging protocol to an imaging preparation state in accordance with a predetermined order (for example, sequentially from the top of the examination order), and also makes preparations for imaging by controlling the X-ray tube  1021  and the sensor  1022  based on imaging conditions included in the unexecuted imaging protocol. The X-ray tube  1021  is controlled by the X-ray generation control unit  1011 , and the sensor  1022  is controlled by the X-ray imaging control unit  1012 . 
     In step S 502 , the control apparatus  101  determines whether the imaging protocol is a tomosynthesis imaging protocol. If the imaging protocol is a tomosynthesis imaging protocol (YES in step S 502 ), the process advances to step S 503 . On the other hand, if the imaging protocol is not a tomosynthesis imaging protocol (NO in step S 502 ), the process advances to step S 505 . 
     In step S 503 , the control apparatus  101  captures a projected image serving as the source of a reconstructed image later. More specifically, the X-ray tube  1021  irradiates the object with X-rays, and the sensor  1022  detects the X-rays transmitted through the object. The image input unit  202  acquires a projected image obtained as a result, and the image processing unit  204  performs image processing such as correction processing, tone processing, or frequency processing for the acquired projected image. The projected image is associated with the examination information and stored in the examination information storage unit  203 . At this time, the imaging screen  301  displays the projected image and additional image information. The projected image is displayed in the preview image display region  302 , and the thumbnail of the projected image is displayed in the thumbnail display region  315  on the tomosynthesis imaging protocol used for the imaging. 
     In step S 504 , according to the pressing of the reconstruction button  307  by the operator via an operation on the operation unit  104 , the control apparatus  101  causes the image processing unit  204  to reconstruct the projected image to generate a tomographic image (reconstructed image). A reconstructed image can be generated not only once but a plurality of times. For example, the operator sometimes generates several reconstructed images while adjusting reconstruction parameters via an operation on the operation unit  104  so as to obtain a reconstructed image suitable for a diagnosis. The thumbnails of the generated reconstructed images are displayed in the thumbnail display regions  316  and  308 . After that, the process advances to step S 404 . 
     In step S 505 , the control apparatus  101  performs imaging using a protocol other than the tomosynthesis imaging protocol, for example, a still imaging protocol. More specifically, the X-ray tube  1021  irradiates the object with X-rays, and the sensor  1022  detects the X-rays transmitted through the object. The image input unit  202  acquires a captured image obtained as a result, and the image processing unit  204  performs image processing such as correction processing, tone processing, or frequency processing for the acquired captured image. The captured image is associated with the examination information and stored in the examination information storage unit  203 . At this time, the imaging screen  301  displays the captured image and additional image information. The captured image is displayed in the preview image display region  302 , and the thumbnail of the captured image is displayed in the thumbnail display region  311  on the imaging protocol  310  used for the imaging. After that, the process advances to step S 404 . 
     Referring back to the flowchart of  FIG. 4 , in step S 404 , the control apparatus  101  determines whether the operator presses the re-imaging button  313  via an operation on the operation unit  104 . For example, if the operator views the image displayed in the preview image display region  302  and determines that the image is inappropriate for a diagnosis, and re-imaging is necessary, the re-imaging button  313  is pressed. If the re-imaging button  313  is pressed (YES in step S 404 ), the process advances to step S 405 . On the other hand, if the re-imaging button  313  is not pressed (NO in step S 404 ), the process advances to step S 406 . 
     In step S 405 , the control apparatus  101  performs re-imaging processing. More specifically, the control apparatus  101  instructs various kinds of operations via the re-imaging instruction unit  206 . First, the rejected image instruction unit  205  changes a captured image designated when the re-imaging button  313  is pressed in step S 404  to a rejected image state under the control of the re-imaging instruction unit  206 . Next, the examination order input unit  201  adds the same imaging protocol as the imaging protocol used to obtain the captured image in the rejected image state to the examination under the control of the re-imaging instruction unit  206 . The re-imaging instruction unit  206  stores the contents of the change by the rejected image instruction unit  205  and the examination order input unit  201  in the examination information storage unit  203 . After that, the process returns to step S 403 . 
     In step S 406 , the control apparatus  101  determines whether the rejected image button  312  is pressed via an operation on the operation unit  104 . For example, assume that the operator views the captured image displayed in the preview image display region  302  and determines that the captured image is inappropriate for a diagnosis. Alternatively, assume that the operator selects one of a plurality of reconstructed images of tomosynthesis imaging as an image appropriate for a diagnosis, as shown in, for example, the thumbnail display regions  316  and  308 , and determines that the remaining images should be changed to a rejected image state not to transfer them to the PACS terminal  30 . As a result, the rejected image button  312  is pressed via an operation on the operation unit  104 . If the rejected image button  312  is pressed (YES in step S 406 ), the process advances to step S 407 . On the other hand, if the rejected image button  312  is not pressed (NO in step S 406 ), the process advances to step S 408 . 
     In step S 407 , the control apparatus  101  causes the rejected image instruction unit  205  to change the designated captured image to the rejected image state, and stores the change contents in the examination information storage unit  203 . After that, the process advances to step S 408 . 
     In step S 408 , the control apparatus  101  determines whether the examination end button  314  is pressed via an operation on the operation unit  104 . For example, the operator determines whether the imaging processes of all imaging protocols are completed by confirming the examination order display region  305  displayed on the display unit  103 . If the operator determines that the imaging processes of all imaging protocols are ended or wants to end the examination, he/she presses the examination end button  314  via the operation unit  104 . If an unexecuted imaging protocol remains, and the examination should be continued, the operator does not press the examination end button  314 . If the examination end button  314  is pressed (YES in step S 408 ), the process advances to step S 409 . On the other hand, if the examination end button  314  is not pressed (NO in step S 408 ), the process returns to step S 403 . 
     In step S 409 , the control apparatus  101  performs examination end processing. More specifically, the examination information output unit  207  outputs, of the information stored in the examination information storage unit  203 , an effective image that is not in the rejected image state and the additional information of the effective image to the PACS terminal  30 , thereby ending the processing. The series of processes of the flowchart in  FIG. 4  thus ends. 
     &lt;Example of Examination Information&gt; 
     An example of examination information according to an embodiment of the present invention will be described next with reference to  FIG. 6 . A table  60  shows some pieces of examination information after the end of an examination, which are stored in the examination information storage unit  203 , in a table format. 
     A protocol number item  601  represents a number assigned to an imaging protocol. The number is incremented like P 001 , P 002 , . . . in the order of addition to an examination order. An imaging protocol item  602  represents the name of an imaging protocol. The imaging protocol is a tomosynthesis imaging protocol or DX imaging protocol. An imaging technique or an imaging part is used as a name in the imaging protocol item  602 , like “tomosynthesis chest” or “DX chest lateral”. 
     A re-imaging source protocol number item  603  is the number of the protocol number item of the re-imaging source assigned to a re-imaging protocol added by the processing of the re-imaging instruction unit  206 . For example, the imaging protocol of protocol number P 003  in the table  60  is an imaging protocol added for re-imaging of imaging protocol P 001 . The re-imaging source protocol number item  603  is blank for an imaging protocol that is not added in re-imaging processing. 
     An image number item  604  represents a number assigned to an image. The number is incremented like IM 001 , IM 002 , . . . in the order of obtaining by imaging or generation. An image type item  605  represents an image type such as a projected image, a reconstructed image, or a still image. An effective/rejected image item  606  represents whether an image is effective or in a rejected image state. 
     This item is a “rejected image” for images changed to the rejected image state by the rejected image instruction unit  205 . This item is “effective” for the remaining images. An imaging success/failure item  607  represents whether an imaging technique has succeeded or failed, and success/failure information identified by the imaging success/failure identification unit  209  is assigned. 
     &lt;Acquisition Processing of Items (Other than Imaging Success/Failure Item  607 ) of Table  60 &gt; 
     What kind of processing is performed up to the end of an examination to obtain the pieces of examination information other than the imaging success/failure item  607  of the table  60  shown in  FIG. 6  will be described below with reference to  FIGS. 4 and 5  again. First, imaging protocols P 001  and P 002  are input in step S 401  of  FIG. 4 , and the examination is started in step S 402 . Imaging is performed first based on tomosynthesis imaging protocol P 001 . For this reason, in the imaging processing and post-processing of step S 403 , the process advances to step S 503  in  FIG. 5 . Projected image IM 001  is thus acquired. 
     Next, assume that reconstructed images IM 002  and IM 003  are acquired based on projected image IM 001  in step S 504 . Note that reconstructed images IM 002  and IM 003  undergo image processing using different reconstruction parameters. If the operator observes reconstructed images IM 002  and IM 003  and understands that the imaging technique for projected image IM 001  has failed, he/she presses the re-imaging button  313  in step S 404 . 
     In step S 405 , all images IM 001 , IM 002 , and IM 003  obtained by imaging protocol P 001  are changed to the rejected image state. Imaging protocol P 003  that is the same as imaging protocol P 001  is added to the examination order. After that, the process returns to step S 403 . To further perform imaging based on re-imaging protocol P 003 , the process similarly advances to step S 503  of  FIG. 5 , and projected image IM 004  is obtained. 
     Next, in step S 504 , reconstructed images IM 005  and IM 006  are acquired based on projected image IM 004 . Note that reconstructed images IM 005  and IM 006  undergo image processing using different reconstruction parameters. Assume that the operator compares reconstructed images IM 005  and IM 006  and determines that reconstructed image IM 006  is more appropriate for a diagnosis. 
     Here, since effective image IM 006  is included, the re-imaging button  313  is not pressed in step S 404 , and the process advances to step S 406 . In step S 406 , to prevent reconstructed image IM 005  inappropriate for a diagnosis from being transferred to the PACS terminal  30 , the rejected image button  312  is pressed. As a result, in step S 407 , reconstructed image IM 005  is changed to the rejected image state. 
     In step S 408 , since unexecuted imaging protocol P 002  remains, the examination end button  314  is not pressed, and the process returns to step S 403 . Since the imaging protocol P 002  is an imaging protocol other than a tomosynthesis imaging protocol, the process advances to step S 505  as a result of determination processing of step S 502 . Still image IM 007  is obtained by imaging in step S 505 . Assume that the operator observes still image IM 007 , understands that the imaging technique has failed, and presses the re-imaging button  313  in step S 404 . 
     In step S 405 , image IM 007  obtained by imaging protocol P 002  is changed to the rejected image state. Imaging protocol P 004  that is the same as imaging protocol P 002  is added to the examination order. After that, the process returns to step S 403 . To further perform imaging using re-imaging protocol P 002 , the process similarly advances to step S 505 , and still image IM 008  is obtained. The operator is assumed to determine that still image IM 008  is appropriate for a diagnosis. 
     Hence, the re-imaging button  313  is not pressed in step S 404 , the rejected image button  312  is not pressed in step S 406 , and the process advances to step S 408 . Here, since the imaging processes of all imaging protocols are completed, the examination end button  314  is pressed in step S 408 , and the examination ends. By the series of processes described above, the items of the table  60  except the imaging success/failure item in  FIG. 6  are obtained. 
     &lt;Acquisition Processing of Imaging Success/Failure Item  607  of Table  60 &gt; 
     The procedure of processing executed by the imaging success/failure identification unit  209  for examination information after the end of the examination according to an embodiment of the present invention will be described next with reference to the flowchart of  FIG. 7 . What kind of processing is performed to obtain the imaging success/failure item  607  of the table  60  shown in  FIG. 6  will be described here. Note that the processing of the imaging success/failure identification unit  209  is executed at an arbitrary timing after the end of the examination until the rejected image statistic output unit  208  outputs information to the rejected image statistic terminal  40 . For example, the processing is executed at the end of examination, at the timing of an execution instruction via the operation unit  104 , or at the timing of information output to the rejected image statistic terminal  40 . 
     In step S 701 , the imaging success/failure identification unit  209  reads out examination information to be processed from the examination information storage unit  203 . Here, the examination information of the table  60  shown in  FIG. 6  is read out. Next, the processes of steps S 702  to S 708  are performed as a loop for the imaging protocols in the examination information sequentially from the top. After the end of the loop, the process advances to step S 709 . First, processing is performed for imaging protocol P 001  at the top in the table  60 . 
     In step S 702 , the imaging success/failure identification unit  209  determines whether the imaging protocol is a tomosynthesis imaging protocol. If the imaging protocol is a tomosynthesis imaging protocol (YES in step S 702 ), the process advances to step S 703 . On the other hand, if the imaging protocol is another imaging protocol (NO in step S 702 ), the process advances to step S 706 . Since imaging protocol P 001  is a tomosynthesis imaging protocol, the process advances to step S 703  here. 
     In step S 703 , the imaging success/failure identification unit  209  determines whether an effective image is included in the projected image and all reconstructed images acquired by the tomosynthesis imaging protocol. Upon determining that an effective image is included (YES in step S 703 ), the process advances to step S 704 . On the other hand, upon determining that no effective image is included (NO in step S 703 ), the process advances to step S 705 . Here, since all images IM 001 , IM 002 , and IM 003  acquired by imaging protocol P 001  are rejected images, the process advances to step S 705 . 
     In step S 705 , the imaging success/failure identification unit  209  assigns imaging failure information to the projected image and all reconstructed images acquired by the tomosynthesis imaging protocol. Here, imaging failure information is assigned to images IM 001 , IM 002 , and IM 003 . After that, the process returns to step S 702  at the start of the loop, and processing is performed for imaging protocol P 003  next. 
     Since imaging protocol P 003  is a tomosynthesis imaging protocol (YES in step S 702 ), the imaging success/failure identification unit  209  advances to step S 703 . Since imaging protocol P 003  includes effective images IM 004  and IM 006  (YES in step S 703 ), the process advances to step S 704 . 
     In step S 704 , the imaging success/failure identification unit  209  assigns imaging success information to the projected image and all reconstructed images acquired by the tomosynthesis imaging protocol. Here, imaging success information is assigned to images IM 004 , IM 005 , and IM 006 . After that, the process returns to step S 702  at the start of the loop, and processing is performed for imaging protocol P 002  next. 
     Since imaging protocol P 002  is not a tomosynthesis imaging protocol (NO in step S 702 ), the process advances to step S 706 . In step S 706 , the imaging success/failure identification unit  209  determines whether the image captured by the imaging protocol is an effective image. If the image is an effective image (YES in step S 706 ), the process advances to step S 707 . On the other hand, if the image is not an effective image (NO in step S 706 ), the process advances to step S 708 . Here, since image IM 007  acquired by imaging protocol P 002  is a rejected image, the process advances to step S 708 . 
     In step S 708 , the imaging success/failure identification unit  209  assigns imaging failure information to the image captured by the imaging protocol. Here, imaging failure information is assigned to image IM 007 . After that, the process returns to step S 702  at the start of the loop, and processing is performed for imaging protocol P 004  next. 
     Since imaging protocol P 004  is not a tomosynthesis imaging protocol (NO in step S 702 ), the process advances to step S 706 . Since image IM 008  acquired by imaging protocol P 004  is an effective image (YES in step S 706 ), the process advances to step S 707 . 
     In step S 707 , the imaging success/failure identification unit  209  assigns imaging success information to the image captured by the imaging protocol. Here, imaging success information is assigned to image IM 008 . Since the loop processing is thus completed for all imaging protocols, the process advances to step S 709 . 
     In step S 709 , the imaging success/failure identification unit  209  stores the examination information changed by the series of processes of steps S 702  to S 708  in the examination information storage unit  203 . By the processes described above, the information of the imaging success/failure item  607  of the table  60  is obtained. 
     &lt;Processing of Rejected Image Statistic Output Unit  208 &gt; 
     The procedure of processing executed by the rejected image statistic output unit  208  according to an embodiment of the present invention will be described next with reference to the flowchart of  FIG. 8 . An example of processing in which after the imaging success/failure identification unit  209  assigns the imaging success/failure item  607  to examination information, the rejected image statistic output unit  208  outputs rejected images and the additional information of the rejected images to the rejected image statistic terminal  40  will be described in detail. The processing of the rejected image statistic output unit  208  is executed at an arbitrary timing after completion of the processing of the imaging success/failure identification unit  209 . For example, the processing is executed at the timing of an execution instruction via the operation unit  104  or executed on the background by designating a desired execution date/time. 
     In step S 801 , the rejected image statistic output unit  208  reads out examination information to be output to the rejected image statistic terminal  40  from the examination information storage unit  203 . In step S 802 , the rejected image statistic output unit  208  extracts, from the examination information read out in step S 801 , captured images to which imaging failure information is assigned by the imaging success/failure identification unit  209  and the additional information of the captured images. In the example of examination information of the table  60  shown in  FIG. 6 , images IM 001 , IM 002 , IM 003 , and IM 007 , and the additional information of these images are extracted. In step S 803 , the rejected image statistic output unit  208  outputs the captured images and the additional information extracted in step S 802  to the rejected image statistic terminal  40 . The series of processes of  FIG. 8  thus ends. 
     As described above, according to this embodiment, it is possible to assign information representing an imaging success/failure state to each captured image independently of information representing a rejected image state. It is also possible to output only captured images with assigned imaging failure information to the rejected image statistic terminal  40 . 
     For example, for images obtained by a tomosynthesis imaging protocol, the imaging failure information can be assigned to all images changed to the rejected image state with the intention of an imaging technique failure, like images IM 001 , IM 002 , and IM 003  of the examination information in the table  60 . Hence, the images can be output to the rejected image statistic terminal  40  as the rejected image analysis target. 
     In addition, for a tomosynthesis imaging protocol including an effective image, like imaging protocol P 003  of the examination information in the table  60 , image IM 005  changed to the rejected image state with the intention of non-transfer is regarded as an imaging success. For this reason, the image is not a rejected image analysis target and is not output to the rejected image statistic terminal  40 . 
     On the other hand, for imaging protocols other than the tomosynthesis imaging protocol, the rejected image state is set with the intention of an imaging technique failure, and the imaging failure information can be assigned to rejected images. Hence, the images can be output as the rejected image analysis target to the rejected image statistic terminal  40 . 
     As described above, only images necessary for rejected image analysis are output to the rejected image statistic terminal  40 . This allows the side of the rejected image statistic terminal  40  to save time to sort necessary images and unnecessary images for rejected image analysis and improve the rejected image analysis efficiency. The improvement of the rejected image analysis efficiency can contribute to improvement of the skill of the imaging technician. Along with the improvement of the skill, ineffective exposure can be reduced, contributing to protection of a patient. 
     Second Embodiment 
     &lt;Outline&gt; 
     The second embodiment is different from the first embodiment in that an image captured by a DX imaging protocol is used as a captured image, and a replicated image is used as a processed image based on the captured image. More specifically, if an image (still image) captured by a DX imaging protocol and replicated images generated from the captured image include an effective image (an image that is not rejected image-instructed), information representing an imaging success is assigned to all images. On the other hand, if no effective image is included, information representing an imaging failure is assigned to all images. Then, each image with the assigned information representing an imaging failure and the additional information of the image are output to a rejected image statistic terminal. The second embodiment will be described below in detail. 
     &lt;Arrangements&gt; 
     The arrangements of a control system and an X-ray imaging system according to this embodiment are the same as in the first embodiment, and a detailed description thereof will be omitted. 
       FIG. 9  is a block diagram showing an example of the arrangement of an X-ray imaging control unit according to an embodiment of the present invention. An X-ray imaging control unit  1012  according to this embodiment includes an image replication unit  901  in addition to the arrangement described with reference to  FIG. 2 . The image replication unit  901  replicates a designated captured image and the additional information of the captured image and stores the replication contents in an examination information storage unit  203 . 
     &lt;Example of Imaging Screen&gt; 
       FIG. 10  shows an example of an imaging screen according to an embodiment of the present invention. The same reference numerals as in  FIG. 3  described in the first embodiment denote the same constituent elements in  FIG. 10 . An examination order display region  305  displays imaging protocols  1001 ,  1002 , and  1003  included in an examination. The name of an imaging technique is displayed in correspondence with each imaging protocol. The imaging protocols are provided with thumbnail display regions  1004 ,  1005 , and  1006  that display the thumbnails of images captured and generated by the imaging protocols. A symbol  1007  representing a rejected image is displayed on the thumbnail of a rejected image. An image replication button  1008  is a button used to instruct image replication. A symbol  1009  representing replication is displayed on the imaging protocol of a replicated image. 
     &lt;Processing&gt; 
     The procedure of a series of processes from the start to the end of an examination according to the second embodiment is the same as the processing shown in  FIG. 4  described in the first embodiment except some differences. The different points will mainly be described below. 
     Details of the processing of step S 403  according to an embodiment of the present invention will be described below with reference to the flowchart of  FIG. 11 . 
     The processing of step S 1101  is the same as the processing of step S 501  in  FIG. 5 , and a description thereof will be omitted. In step S 1102 , a control apparatus  101  executes imaging using an imaging protocol. More specifically, an X-ray tube  1021  irradiates an object with X-rays, and a sensor  1022  detects the X-rays transmitted through the object. An image input unit  202  acquires a captured image obtained as a result, and an image processing unit  204  performs image processing such as correction processing, tone processing, or frequency processing for the acquired captured image. The captured image is associated with examination information and stored in the examination information storage unit  203 . At this time, an imaging screen  301  displays the captured image and additional image information. The captured image is displayed in a preview image display region  302 , and the thumbnail of the captured image is displayed in the thumbnail display regions  1004 ,  1005 , and  1006  on the imaging protocol used for the imaging. 
     In step S 1103 , the control apparatus  101  determines whether the image replication button  1008  is pressed via an operation on an operation unit  104 . If the image replication button  1008  is pressed (YES in step S 1103 ), the process advances to step S 1104 . On the other hand, if the image replication button  1008  is not pressed (NO in step S 1103 ), the processing ends. In step S 1104 , the control apparatus  101  causes the image replication unit  901  to replicate a designated captured image and the additional information of the image, and stores the replication contents in the examination information storage unit  203 . The series of processes in  FIG. 11  thus ends. 
     &lt;Example of Examination Information&gt; 
     An example of examination information according to an embodiment of the present invention will be described next with reference to  FIG. 12 . A table  120  shows some pieces of examination information after the end of an examination, which are stored in the examination information storage unit  203 , in a table format. 
     A replication source image number item  1201  is the number of an image number item  604  of a replication source, which is assigned to an image replicated by the processing of the image replication unit  901 . The remaining items are the same as those of the table  60  shown in  FIG. 6  described in the first embodiment, and a description thereof will be omitted. 
     &lt;Acquisition Processing of Items (Other than Imaging Success/Failure Item  607 ) of Table  120 &gt; 
     What kind of processing is performed up to the end of an examination to obtain the pieces of examination information other than an imaging success/failure item  607  of the table  120  shown in  FIG. 12  will be described below with reference to  FIGS. 4  and  5  again. 
     First, imaging protocols P 005  and P 006  are input in step S 401  of  FIG. 4 , and the examination is started in step S 402 . In the imaging processing and post-processing of step S 403 , first, imaging is performed based on imaging protocol P 005  in steps S 1101  and S 1102  of  FIG. 11 . Projected image IM 009  is thus acquired. 
     To perform a plurality of different image processes and compare images, the image replication button  1008  is pressed in step S 1103 . As a result, replicated images IM 010  and IM 011  of captured image IM 009  are acquired in step S 1104 . Note that there is a mechanism for associating imaging protocol P 005  with a captured image in a one-to-one correspondence. For this reason, along with the image replication, imaging protocols P 007  and P 008  to be associated with the replicated images IM 010  and IM 011 , respectively, are replicated based on imaging protocol P 005 . Images IM 009 , IM 010 , and IM 011  undergo image processing using different image processing parameters. 
     Assume that the operator compares all images IM 009 , IM 010 , and IM 011 , understands that the imaging technique for captured image IM 009  has failed, and presses a re-imaging button  313  in step S 404  of  FIG. 4 . By the subsequent processing of step S 405 , first, images IM 009 , IM 010 , and IM 011  are changed to the rejected image state. Imaging protocol P 009  that is the same as imaging protocol P 005  is added to the examination order. 
     Next, the process returns to step S 403 . To further perform imaging based on re-imaging protocol P 009 , the process advances to step S 1102 , and captured image IM 012  is acquired. In step S 1104 , replicated images IM 013  and IM 014  of captured image IM 012  are acquired. Note that along with the image replication, imaging protocols P 010  and P 011  to be associated with the replicated images IM 013  and IM 014 , respectively, are replicated based on imaging protocol P 009 . Images IM 012 , IM 013 , and IM 014  undergo image processing using different image processing parameters. 
     Assume that the operator compares images IM 012 , IM 013 , and IM 014 , and determines that image IM 014  is most appropriate for a diagnosis. Here, since effective image IM 014  is included, the re-imaging button  313  is not pressed in step S 404 , and the process advances to step S 406 . In step S 406 , to prevent images IM 012  and IM 013  inappropriate for a diagnosis from being transferred to a PACS terminal  30 , a rejected image button  312  is pressed. Next, in step S 407 , images IM 012  and IM 013  are changed to the rejected image state. Since unexecuted imaging protocol P 006  remains, an examination end button  314  is not pressed in step S 408 , and the process returns to step S 403 . 
     Next, captured image IM 015  is acquired by the imaging in step S 1102 . If the operator determines that captured image IM 015  need not be compared based on a plurality of image processes, the image replication button  1008  is not pressed in step S 1103 . Here, assume that the operator observes captured image IM 015 , understands that the imaging technique has failed, and presses the re-imaging button  313  in step S 404 . Next, image IM 015  obtained by imaging protocol P 006  is changed to the rejected image state by the processing of step S 405 . Imaging protocol P 012  that is the same as imaging protocol P 006  is added to the examination order. 
     Next, the process returns to step S 403 . To further perform imaging using re-imaging protocol P 012 , the process advances to step S 1102 , and captured image IM 016  is acquired. The operator is assumed to determine that captured image IM 016  is appropriate for a diagnosis. In this case, the re-imaging button  313  is not pressed in step S 404 , the rejected image button  312  is not pressed in step S 406 , and the process advances to step S 408 . Since the imaging processes of all imaging protocols are completed, the examination end button  314  is pressed in step S 408 , and the examination ends. 
     By the series of processes described above, the items of the table  120  except the imaging success/failure item in  FIG. 12  are obtained. 
     &lt;Acquisition Processing of Imaging Success/Failure Item  607  of Table  120 &gt; 
     The procedure of processing executed by an imaging success/failure identification unit  209  for examination information after the end of the examination according to an embodiment of the present invention will be described next with reference to the flowchart of  FIG. 13 . What kind of processing is performed to obtain the imaging success/failure item  607  of the table  120  shown in  FIG. 12  will be described here. 
     In step S 1301 , the imaging success/failure identification unit  209  reads out examination information to be processed from the examination information storage unit  203 . Here, the examination information of the table  120  shown in  FIG. 12  is read out. Next, the processes of steps S 1302  to S 1309  are performed as a loop for the images in the examination information sequentially from the top. After the end of the loop, the process advances to step S 1310 . First, processing is performed for image IM 009  at the top in the table  120 . 
     In step S 1302 , the imaging success/failure identification unit  209  determines whether the image is an original image or a replicated image. If the image is an original image (YES in step S 1302 ), the process advances to step S 1303 . On the other hand, if the image is a replicated image, the process returns to the start of the loop, and processing is performed for the next image. Here, since image IM 009  is an original image, the process advances to step S 1303 . 
     In step S 1303 , the imaging success/failure identification unit  209  determines whether a replicated image of the image exists. If a replicated image exists (YES in step S 1303 ), the process advances to step S 1304 . On the other hand, if no replicated image exists (NO in step S 1303 ), the process advances to step S 1307 . Here, since image IM 009  has replicated images IM 010  and IM 011 , the process advances to step S 1304 . 
     In step S 1304 , the imaging success/failure identification unit  209  determines whether an effective image is included in the image and all replicated images of the image. If an effective image is included (YES in step S 1304 ), the process advances to step S 1305 . On the other hand, if no effective image is included (NO in step S 1304 ), the process advances to step S 1306 . Here, since all of original image IM 009  and replicated images IM 010  and IM 011  are in the rejected image state, the process advances to step S 1306 . 
     In step S 1306 , the imaging success/failure identification unit  209  assigns imaging failure information to all of the image and the replicated images of the image. Here, imaging failure information is assigned to images IM 009 , IM 010 , and IM 011 . After that, the process returns to step S 1302  at the start of the loop. 
     As the result of determination of step S 1302 , processing for replicated images IM 010  and IM 011  is not performed (NO in step S 1302 ), and the loop advances to next original image IM 012 . Since image IM 012  is an original image (YES in step S 1302 ), the process advances to step S 1303 . Here, since image IM 012  has replicated images IM 013  and IM 014  (YES in step S 1303 ), the process advances to step S 1304 . Since replicated image IM 014  is an effective image among original image IM 012  and replicated images IM 013  and IM 014  (YES in step S 1304 ), the process advances to step S 1305 . 
     In step S 1305 , the imaging success/failure identification unit  209  assigns imaging success information to all of the image and the replicated images of the image. Here, imaging success information is assigned to images IM 012 , IM 013 , and IM 014 . After that, the process returns to step S 1302  at the start of the loop. 
     As the result of determination of step S 1302 , processing for replicated images IM 013  and IM 014  is not performed (NO in step S 1302 ), and the loop advances to next original image IM 015 . Since image IM 015  is an original image (YES in step S 1302 ), the process advances to step S 1303 . Since image IM 015  has no replicated image (NO in step S 1303 ), the process advances to step S 1307 . 
     In step S 1307 , the imaging success/failure identification unit  209  determines whether the image is an effective image. If the image is an effective image (YES in step S 1307 ), the process advances to step S 1308 . On the other hand, if the image is not an effective image (NO in step S 1307 ), the process advances to step S 1309 . Here, since image IM 015  is a rejected image (NO in step S 1307 ), the process advances to step S 1309 . 
     In step S 1309 , the imaging success/failure identification unit  209  assigns imaging failure information to the image. Here, imaging failure information is assigned to image IM 015 . After that, the process returns to step S 1302  at the start of the loop, and processing is performed for image IM 016  next. Since image IM 016  is an original image (YES in step S 1302 ), the process advances to step S 1303 . Since image IM 016  has no replicated image (NO in step S 1303 ), the process advances to step S 1307 . Since image IM 016  is an effective image (YES in step S 1307 ), the process advances to step S 1308 . 
     In step S 1308 , the imaging success/failure identification unit  209  assigns imaging success information to the image. Here, imaging success information is assigned to image IM 016 . Since the loop processing is thus completed for all images, the process advances to step S 1310 . In step S 1310 , the imaging success/failure identification unit  209  stores the examination information changed by the series of processes of steps S 1302  to S 1309  in the examination information storage unit  203 . By the processes described above, the information of the imaging success/failure item  607  of the table  120  is obtained. 
     &lt;Processing of Rejected Image Statistic Output Unit  208 &gt; 
     The processing of a rejected image statistic output unit  208  according to this embodiment is basically the same as the processing shown in  FIG. 8  of the first embodiment. In the example of the table  120  shown in  FIG. 12 , however, the second embodiment is different in that images IM 009 , IM 010 , IM 011 , and IM 015  are extracted in step S 802 . 
     As described above, according to this embodiment, it is possible to assign information representing an imaging success/failure state to each captured image independently of information representing a rejected image state. It is also possible to output only captured images with assigned imaging failure information to a rejected image statistic terminal  40 . 
     For example, for captured images having replicated images, the imaging failure information can be assigned to all images changed to the rejected image state with the intention of an imaging technique failure, like images IM 009 , IM 010 , and IM 011  of the examination information in the table  120 . Hence, the images can be output to the rejected image statistic terminal  40  as the rejected image analysis target. 
     In addition, for captured images having replicated images in the examination information of the table  120 , each of images IM 012  and IM 013  changed to the rejected image state with the intention of non-transfer is regarded as an imaging success. For this reason, the images are not rejected image analysis targets and are not output to the rejected image statistic terminal  40 . 
     On the other hand, for captured images having no replicated image, the rejected image state is set with the intention of an imaging technique failure, and the imaging failure information can be assigned to rejected images. Hence, the images can be output as the rejected image analysis target to the rejected image statistic terminal  40 . 
     As described above, only images necessary for rejected image analysis are output to the rejected image statistic terminal  40 . This allows the side of the rejected image statistic terminal  40  to save time to sort necessary images and unnecessary images for rejected image analysis and improve the rejected image analysis efficiency. 
     Third Embodiment 
     &lt;Outline&gt; 
     In the first embodiment, the target to be output to the rejected image statistic terminal includes an image with assigned information representing an imaging failure and the additional information of the image. The third embodiment is different from that first embodiment in that the target to be output to the rejected image statistic terminal includes a rejected image with assigned imaging success/failure information and the additional information of the rejected image. 
     &lt;Arrangement&gt; 
     The arrangements of a control system and an X-ray imaging system according to this embodiment are the same as in the first embodiment, and a detailed description thereof will be omitted. In addition, the arrangement of an X-ray imaging control unit  1012  according to this embodiment is the same as that described with reference to  FIGS. 1 and 2  in the first embodiment. An example of an imaging screen according to this embodiment is the same as in  FIG. 3  of the first embodiment. A series of processes from the start to the end of an examination according to this embodiment is also the same as the processes shown in  FIGS. 4 and 5 . Processing for obtaining examination information is also the same as the processes shown in  FIGS. 6 and 7 . 
     &lt;Processing of Rejected Image Statistic Output Unit  208 &gt; 
     The procedure of processing executed by a rejected image statistic output unit  208  according to an embodiment of the present invention will be described next with reference to the flowchart of  FIG. 14 . An example of processing in which after an imaging success/failure identification unit  209  assigns imaging success/failure information to examination information, the rejected image statistic output unit  208  outputs rejected images and the additional information of the rejected images to a rejected image statistic terminal  40  will be described in detail. 
     The processing of step S 1401  is the same as the processing of step S 801  of  FIG. 8 . In step S 1402 , the rejected image statistic output unit  208  extracts images in the rejected image state and the additional information of the images from the examination information read out in step S 1401 . In the example of examination information of a table  60  shown in  FIG. 6 , images IM 001 , IM 002 , IM 003 , IM 005 , and IM 007  are extracted. The processing of step S 1403  is the same as the processing of step S 803  of  FIG. 8 . 
     As described above, according to this embodiment, it is possible to assign information representing an imaging success/failure state to each captured image independently of information representing a rejected image state. 
     For example, for images obtained by a tomosynthesis imaging protocol, the imaging failure information can be assigned to all images changed to the rejected image state with the intention of an imaging technique failure, like images IM 001 , IM 002 , and IM 003  of the examination information in the table  60 . In addition, for a tomosynthesis imaging protocol including an effective image, like imaging protocol P 003  of the examination information in the table  60 , image IM 005  changed to the rejected image state with the intention of non-transfer represents an imaging success. 
     On the other hand, for imaging protocols other than the tomosynthesis imaging protocol, the rejected image state is set with the intention of an imaging technique failure, and the imaging failure information can be assigned to rejected images. In this way, all rejected images to which information representing an imaging success/failure state is assigned are output to the rejected image statistic terminal  40 . However, the side of the rejected image statistic terminal  40  need only perform filtering to refer to only imaging failure images at the time of rejected image analysis. This allows the side of the rejected image statistic terminal  40  to save time to sort necessary images and unnecessary images for rejected image analysis and improve the rejected image analysis efficiency. 
     Fourth Embodiment 
     &lt;Outline&gt; 
     In the second embodiment, the target to be output to the rejected image statistic terminal includes an image with assigned information representing an imaging failure and the additional information of the image. The fourth embodiment is different from that second embodiment in that the target to be output to the rejected image statistic terminal includes a rejected image with assigned imaging success/failure information and the additional information of the rejected image. 
     &lt;Arrangement&gt; 
     The arrangements of a control system and an X-ray imaging system according to this embodiment are the same as in the first embodiment, and a detailed description thereof will be omitted. In addition, the arrangement of an X-ray imaging control unit  1012  according to this embodiment is the same as that described with reference to  FIG. 9  in the second embodiment. An example of an imaging screen according to this embodiment is the same as in  FIG. 10  of the second embodiment. A series of processes from the start to the end of an examination according to this embodiment is also the same as the processes shown in  FIGS. 4 and 11 . Processing for obtaining examination information is also the same as the processes shown in  FIGS. 12 and 13  of the second embodiment. 
     &lt;Processing of Rejected Image Statistic Output Unit  208 &gt; 
     The procedure of processing executed by a rejected image statistic output unit  208  according to an embodiment of the present invention will be described next with reference to the flowchart of  FIG. 14 . The processing of step S 1401  is the same as the processing of step S 801  of  FIG. 8 . In step S 1402 , the rejected image statistic output unit  208  extracts images in the rejected image state and the additional information of the images from the examination information read out in step S 1401 . In the example of examination information of a table  120  shown in  FIG. 12 , images IM 009 , IM 010 , IM 011 , IM 012 , IM 013 , and IM 015  are extracted. The processing of step S 1403  is the same as the processing of step S 803  of  FIG. 8 . 
     As described above, according to the fourth embodiment, it is possible to assign information representing an imaging success/failure state to each captured image independently of information representing a rejected image state. 
     For example, for captured images having replicated images, the imaging failure information can be assigned to all images changed to the rejected image state with the intention of an imaging technique failure, like images IM 009 , IM 010 , and IM 011  in the table  120 . In addition, for captured images having replicated images in the table  120 , each of images IM 012  and IM 013  changed to the rejected image state with the intention of non-transfer is regarded as an imaging success. 
     On the other hand, for captured images having no replicated image, the rejected image state is set with the intention of an imaging technique failure, and the imaging failure information can be assigned to rejected images. In this way, all rejected images to which information representing an imaging success/failure state is assigned are output to a rejected image statistic terminal  40 . However, the side of the rejected image statistic terminal  40  need only perform filtering to refer to only imaging failure images at the time of rejected image analysis. This allows the side of the rejected image statistic terminal  40  to save time to sort necessary images and unnecessary images for rejected image analysis and improve the rejected image analysis efficiency. 
     Fifth Embodiment 
     &lt;Outline&gt; 
     In the fifth embodiment, an example will be described in which an imaging success/failure identification unit is provided outside a control apparatus, and information representing an imaging success/failure is assigned to an image stored in a rejected image statistic terminal, unlike the first embodiment. 
     &lt;Arrangements&gt; 
       FIG. 15  is a block diagram showing an example of the arrangement of a control system according to the fifth embodiment. The same reference numerals as in  FIG. 1  described in the first embodiment denote the same constituent elements in  FIG. 15 . Reference numeral  1501  denotes an imaging success/failure identification unit. The imaging success/failure identification unit  1501  identifies, based on the additional information of a rejected image stored in a rejected image statistic terminal  40 , whether the rejected image is generated by an imaging failure. 
       FIG. 16  shows an example of a functional arrangement configured to implement the fifth embodiment in an X-ray imaging control unit  1012  shown in  FIG. 15 . Note that the same reference numerals as in  FIG. 2  described in the first embodiment denote the same constituent elements in  FIG. 16 . The X-ray imaging control unit  1012  according to this embodiment is different from that in  FIG. 2  in that an imaging success/failure identification unit  209  is not included. 
     An example of an imaging screen according to the fifth embodiment is the same as the first embodiment, as shown in  FIG. 3 . A series of procedures from the start to the end of an examination according to the fifth embodiment is the same as in  FIGS. 4 and 5  described in the first embodiment. An example of processing for obtaining examination information necessary for an explanation of the function of the fifth embodiment is the same as in  FIG. 6  described in the first embodiment. 
     An example of processing of casing a rejected image statistic output unit  208  to output a rejected image and the additional information of the rejected image to the rejected image statistic terminal  40  after the end of an examination in the fifth embodiment is the same as in  FIG. 14  described in the third embodiment. Note that the processing of the rejected image statistic output unit  208  is executed at an arbitrary timing after the end of the examination. For example, the processing is executed by instructing execution via an operation unit  104  or executed on the background by designating a desired execution date/time. 
     The procedure of processing of the imaging success/failure identification unit  1501  after information output from the rejected image statistic output unit  208  is input to the rejected image statistic terminal  40  in the fifth embodiment is the same as in  FIG. 7  described in the first embodiment, and only some different points will be described. Note that the processing of the imaging success/failure identification unit  1501  is executed at an arbitrary timing after information output from the rejected image statistic output unit  208  is input to the rejected image statistic terminal  40  until the rejected image statistic terminal  40  performs rejected image analysis. For example, the processing is executed immediately after reception of an input from the rejected image statistic output unit  208 , at the timing of an execution instruction via an operation unit (not shown) of the rejected image statistic terminal  40 , or at the timing of rejected image analysis by the rejected image statistic terminal  40 . 
     In step S 701  according to the fifth embodiment, a rejected image associated with examination information as a processing target and additional information are read out from the rejected image statistic terminal  40 . Here, a rejected image associated with examination information and additional information are read out in accordance with a table  60  shown in  FIG. 6 . 
     In step S 709  according to the fifth embodiment, information changed by a series of processes of steps S 702  to S 708  is stored in the rejected image statistic terminal  40 . By the processes described above, the imaging success/failure item of the table  60  is obtained. 
     As described above, according to this embodiment, it is possible to assign information representing an imaging success/failure state to each rejected image stored in the rejected image statistic terminal  40  independently of information representing a rejected image state. 
     For example, for images obtained by a tomosynthesis imaging protocol, the imaging failure information can be assigned to all images changed to the rejected image state with the intention of an imaging technique failure, like images IM 001 , IM 002 , and IM 003  of the examination information in the table  60 . In addition, for a tomosynthesis imaging protocol including an effective image, like imaging protocol P 003  of the examination information in the table  60 , image IM 005  changed to the rejected image state with the intention of non-transfer is regarded as an imaging success. 
     On the other hand, for imaging protocols other than the tomosynthesis imaging protocol, the rejected image state is set with the intention of an imaging technique failure, and the imaging failure information can be assigned to rejected images. Although all rejected images are output from the rejected image statistic output unit  208  to the rejected image statistic terminal  40 , the side of the rejected image statistic terminal  40  need only assign the information representing the imaging success/failure state and perform filtering to refer to only imaging failure images at the time of rejected image analysis. This allows the side of the rejected image statistic terminal  40  to save time to sort necessary images and unnecessary images for rejected image analysis and improve the rejected image analysis efficiency. 
     Sixth Embodiment 
     &lt;Outline&gt; 
     In the sixth embodiment, an example will be described in which an imaging success/failure identification unit is provided outside a control apparatus, and information representing an imaging success/failure is assigned to an image stored in a rejected image statistic terminal, unlike the second embodiment. 
     &lt;Arrangements&gt; 
     The arrangement of a control system according to the sixth embodiment is the same as in  FIG. 15  described in the fifth embodiment.  FIG. 17  shows an example of a functional arrangement configured to implement the sixth embodiment in an X-ray imaging control unit  1012  shown in  FIG. 15 . The same reference numerals as in  FIG. 9  described in the second embodiment denote the same constituent elements in FIG.  17 . The X-ray imaging control unit  1012  according to this embodiment is different from that in  FIG. 9  in that an imaging success/failure identification unit  209  is not included. 
     An example of an imaging screen according to the sixth embodiment is the same as in  FIG. 10  described in the second embodiment. A series of procedures from the start to the end of an examination according to the sixth embodiment is the same as in  FIGS. 4 and 11  described in the second embodiment. An example of processing for obtaining examination information necessary for an explanation of the function of the sixth embodiment is the same as in  FIG. 12  described in the second embodiment. 
     An example of processing of casing a rejected image statistic output unit  208  to output a rejected image and the additional information of the rejected image to the rejected image statistic terminal  40  after the end of an examination in the sixth embodiment is the same as in  FIG. 14  described in the third embodiment. Note that the processing of the rejected image statistic output unit  208  is executed at an arbitrary timing after the end of the examination. For example, the processing is executed by instructing execution via an operation unit  104  or executed on the background by designating a desired execution date/time. 
     The procedure of processing of an imaging success/failure identification unit  1501  after information output from the rejected image statistic output unit  208  is input to the rejected image statistic terminal  40  in the sixth embodiment is the same as in  FIG. 13  described in the second embodiment, and only some different points will be described. Note that the processing of the imaging success/failure identification unit  1501  is executed at an arbitrary timing after information output from the rejected image statistic output unit  208  is input to the rejected image statistic terminal  40  until the rejected image statistic terminal  40  performs rejected image analysis. For example, the processing is executed immediately after reception of an input from the rejected image statistic output unit  208 , at the timing of an execution instruction via an operation unit (not shown) of the rejected image statistic terminal  40 , or at the timing of rejected image analysis by the rejected image statistic terminal  40 . 
     In step S 1301  according to the sixth embodiment, a rejected image associated with examination information as a processing target and additional information are read out from the rejected image statistic terminal  40 . Here, a rejected image associated with examination information and additional information are read out in accordance with a table  120  shown in  FIG. 12 . 
     In step S 1310  according to the sixth embodiment, information changed by a series of processes of steps S 1302  to S 1309  is stored in the rejected image statistic terminal  40 . By the processes described above, the imaging success/failure item of the table  120  is obtained. 
     As described above, according to this embodiment, it is possible to assign information representing an imaging success/failure state to each rejected image stored in the rejected image statistic terminal  40  independently of information representing a rejected image state. 
     For example, for captured images having replicated images, the imaging failure information can be assigned to all images changed to the rejected image state with the intention of an imaging technique failure, like images IM 009 , IM 010 , and IM 011  in the table  120 . In addition, for captured images having replicated images in the table  120 , each of images IM 012  and IM 013  changed to the rejected image state with the intention of non-transfer is regarded as an imaging success. 
     On the other hand, for captured images having no replicated image, the rejected image state is set with the intention of an imaging technique failure, and the imaging failure information can be assigned to rejected images. Although all rejected images are output from the rejected image statistic output unit  208  to the rejected image statistic terminal  40 , the side of the rejected image statistic terminal  40  need only assign the information representing the imaging success/failure state and perform filtering to refer to only imaging failure images at the time of rejected image analysis. This allows the side of the rejected image statistic terminal  40  to save time to sort necessary images and unnecessary images for rejected image analysis and improve the rejected image analysis efficiency. 
     According to the present invention, it is possible to save time to select images necessary for rejected image analysis and improve the rejected image analysis efficiency. 
     Other Embodiments 
     Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
     This application claims the benefit of Japanese Patent Application No. 2016-159680, filed Aug. 16, 2016, which is hereby incorporated by reference wherein in its entirety.