JP5677534B2 - Radiation imaging apparatus and control method thereof - Google Patents

Description

  The present invention relates to a radiation imaging apparatus and a control method thereof.

  A radiation (eg, X-ray) tube is constructed using a thermionic source. The X-ray tube emits thermoelectrons from a filament heated to a high temperature and accelerates the electron beam to high energy via a Wehnelt electrode, an extraction electrode, an acceleration electrode, and a lens electrode. Then, after forming an electron beam in a desired shape, an X-ray target made of metal is irradiated to generate X-rays.

  In recent years, a cold cathode type electron source has been developed as an electron source to replace this thermionic source. Cold cathode electron sources have been widely studied as applications for flat panel displays (FPD). As a typical cold cathode, a Spindt type electron source that takes out electrons by applying a high electric field to the tip of a needle of several tens of nanometers is known. Also known are electron-emitting emitters made of carbon nanotubes (CNT), and surface-conduction electron sources that emit electrons by forming a fine structure on the order of nm on the surface of a glass substrate.

  As applications of these electron sources, Patent Documents 1 and 2 propose a technique for forming a single electron beam using a Spindt-type electron source or a carbon nanotube-type electron source to extract X-rays. . Patent Document 3 and Non-Patent Document 1 propose techniques for generating X-rays by irradiating an X-ray target with an electron beam from a multi-electron source using a plurality of these cold cathode electron sources. Furthermore, Patent Document 4 discloses a technique for generating a multi-X-ray beam having excellent characteristics without mutual interference from a multi-X-ray source.

  The radiation imaging apparatus is used for various applications. As one of them, for example, there is a mammography apparatus that captures a breast and obtains radiation images such as a breast, a tumor, and calcification. In a mammography apparatus, since a mammogram is obtained as a result of projection, the mammary gland may sometimes overlap with calcification or a tumor and become unclear. About half of the reasons for reexamination of mammography are due to this overlap with mammary tissue. Therefore, Patent Document 5 describes a clinical method by driving an X-ray source to a position along the compression direction, acquiring a plurality of X-ray images corresponding to a set of exposure, and performing reconstruction by tomosynthesis. A technique for generating a three-dimensional image of a suspicious area of particular interest has been proposed.

JP-A-9-180894 JP 2004-329784 A JP-A-8-264139 JP 2007-265981 A Japanese Patent Laid-Open No. 2007-216022

Applied Physics Letters 86,184104 (2005), J. Zhang `` Stationary scanning x-ray source based on carbon nanotube field emitters ''

  In the mammography apparatus, in general, imaging is performed from two directions by head-to-tail imaging (CC imaging) and inner / outer oblique direction imaging (MLO imaging). At this time, in each imaging, the breast is imaged from the direction along the compression direction, but it may be preferable to change the X-ray incident direction depending on the calcification distribution shape and the tumor shape.

  However, an appropriate X-ray incident direction cannot be known in advance. In fluoroscopic imaging other than mammography, a high-resolution, high-dose still image is acquired after determining an appropriate imaging direction. However, in breast imaging, the X-ray source is located above the head. If the patient moves at high speed, it may cause fear to the patient.

  In addition, since the X-ray source performs imaging in a stopped state, if the X-ray source moves, the apparatus itself vibrates, and the vibration remains during imaging, and a blurred image may be captured. . When shooting is performed with time until vibration is eliminated, the time required for shooting becomes longer. In this case, since the patient is in a state where the breast is still compressed, it causes great pain to the patient.

  Accordingly, the present invention has been made in view of the above problems, and a radiographic apparatus capable of obtaining a radiographic image that is not easily affected by the distribution of mammary glands without mechanically moving the electron source and the same. An object is to provide a control method.

In order to achieve the above object, one embodiment of the present invention provides:
A radiographic apparatus for taking radiographic images,
Radiation generating means for irradiating a subject with a plurality of radiation generated using a plurality of radiation generating sources arranged in a one-dimensional manner ;
Radiation detecting means for capturing a plurality of first radiation images based on detection of a plurality of radiations having different irradiation angles transmitted through the subject;
Selecting means for selecting, from among the plurality of radiation generation sources, a radiation generation source for irradiating the object region identified based on the plurality of first radiation images;
A grid that is disposed between the subject and the radiation detection means and absorbs scattered radiation scattered by the subject,
The arrangement direction of the plurality of radiation sources arranged in a one-dimensional manner is parallel to the stripe direction of the grid .

  According to the present invention, it is possible to obtain a radiation image that is not easily affected by the distribution of mammary glands without mechanically moving the electron source. In addition, since the electron source need not be moved mechanically but only to be switched electrically, the photographing time can be shortened.

The figure which shows an example of a structure of the mammography apparatus 100 concerning one embodiment of this invention. The figure which shows an example of a structure of the multi X-ray source generation part 14 shown in FIG. The figure which shows an example of a functional structure of the control apparatus 20 shown in FIG. The 1st figure for demonstrating the outline | summary of the process by the determination part 25 shown in FIG. The 2nd figure for demonstrating the outline | summary of the process by the determination part 25 shown in FIG. 3 is a flowchart illustrating an example of a flow of imaging processing in the mammography apparatus 100 illustrated in FIG. 1. The figure for demonstrating an example of the arrangement position of a grid. The figure for demonstrating an example of the direction of a grid stripe. The figure for demonstrating an example of the flow of a process at the time of imaging | photography of a breast on either side. FIG. 9 is a diagram illustrating an example of a functional configuration of a control device 20 according to a fourth embodiment.

  Hereinafter, an embodiment of a radiation imaging apparatus and a control method thereof according to the present invention will be described in detail with reference to the accompanying drawings. In the embodiment described below, a case where X-rays are applied as radiation will be described as an example. However, radiation is not limited to X-rays, and may be electromagnetic waves, α rays, β rays, γ rays, or the like. May be. In the following embodiment, a case where the radiation imaging apparatus according to the present invention is applied to a mammography apparatus will be described as an example.

(Embodiment 1)
FIG. 1 is a diagram showing an example of the configuration of a mammography apparatus 100 according to an embodiment of the present invention.

  The mammography apparatus 100 includes one or more computers. The computer includes, for example, main control means such as a CPU and storage means such as ROM (Read Only Memory) and RAM (Random Access Memory). The computer may be provided with communication means such as a network card, input / output means such as a keyboard, mouse, display, or touch panel. These constituent units are connected by a bus or the like, and are controlled by the main control unit executing a program stored in the storage unit.

  The mammography apparatus 100 includes an imaging apparatus 10 and a control apparatus 20. The imaging device 10 captures an X-ray image. The control device 20 controls the overall processing in the mammography apparatus 100. The subject M indicates, for example, the breast of a patient (human body).

  Here, the imaging apparatus 10 includes a C-arm 11, a two-dimensional detector 12, a compression plate 13, and a multi X-ray source generation unit 14.

  The compression plate 13 compresses the breast and stretches the breast thinly. The compression plate 13 is made of a material having sufficient strength and good X-ray permeability. The C arm 11 is composed of a C-shaped arm member. At both ends of the C-arm 11, a multi-X-ray source generator 14 and a two-dimensional detector 12 are provided facing each other.

  The multi X-ray source generation unit 14 functions as a radiation generation unit, and irradiates (exposes) a plurality of radiations (X-rays) toward a subject (for example, a patient). The multi X-ray source generation unit 14 may be realized using, for example, the technique disclosed in Japanese Patent Application Laid-Open No. 2007-265981. Briefly, the multi X-ray source generator 14 is provided with a plurality of electron-emitting devices 35 as electron sources (X-ray sources). Then, an electron beam is emitted from the plurality of electron-emitting devices 35 to irradiate the transmission target 15. Thereby, X-rays are generated and the subject is irradiated with the X-rays. The electron-emitting devices 35 are arranged in a two-dimensional NxM on the device array 36 as shown in FIG. That is, they are two-dimensionally arranged on a plane orthogonal to the X-ray image capturing direction. The transmission target 15 is provided corresponding to the electron-emitting device 35 and irradiates the subject (for example, under the patient's chin) with X-rays from all or part of the two-dimensional NxM points. As described with reference to FIG. 2, in the present embodiment, the electron-emitting devices 35 and the transmission target 15 are arranged in a two-dimensional manner, but may be arranged in a one-dimensional manner. A plurality of X-rays emitted from the transmission target 15 (X-ray focal point) of the multi-X-ray source generation unit 14 passes through the subject M via the compression plate 13 and reaches the two-dimensional detector 12. Thereby, a plurality of X-ray images having different X-ray irradiation angles are taken. In addition, each of the plurality of electron-emitting devices 35 is individually controlled in the amount of electron emission by drive signals S1 and S2 from the control device 20. That is, on / off of a plurality of X-rays can be controlled by individually controlling the electron emission amount of the element array 36 by the matrix signals of the drive signals S1 and S2.

  The two-dimensional detector 12 functions as a radiation detection unit and detects X-rays transmitted through the subject. As a result, the mammography apparatus 100 captures an X-ray image based on the subject. For the two-dimensional detector 12, for example, an amorphous selenium sensor or amorphous silicon is used. The external shape of the entire sensor of the two-dimensional detector 12 is, for example, about 24 cm × 30 cm.

  Next, an example of a functional configuration of the control device 20 illustrated in FIG. 1 will be described with reference to FIG.

  The control device 20 includes an image processing unit 21, an image display unit 22, a control unit 23, an operation unit 24, a determination unit 25, and an area specifying unit 26 as functional configurations. The

  The image processing unit 21 performs image processing on the X-ray image based on the X-ray intensity distribution detected by the two-dimensional detector 12. Specifically, a reconstruction process is performed on a plurality of X-ray images having different X-ray irradiation angles to generate a plurality of tomographic images. The reconstruction process may be performed using, for example, filtered back projection (FBP). In the calculation process by FBP, the measured projection is filtered and the image is backprojected. A plurality of tomographic images obtained by the reconstruction process represent structures in a plane parallel to the two-dimensional detector 12. That is, the plurality of tomographic images correspond to planes at different distances from the two-dimensional detector 12.

  The image display unit 22 performs display based on the X-ray image processed by the image processing unit 21. The image display unit 22 is realized by, for example, a liquid crystal display. The operation unit 24 inputs an operator's instruction into the device (control device 20). The operation unit 24 is realized by a mouse, a keyboard, or the like, for example. The image display unit 22 and the operation unit 24 may be realized by a touch panel integrated with each other.

  The region specifying unit 26 specifies a target region from a plurality of X-ray images having different X-ray irradiation angles (specifically, a plurality of tomographic images generated by the image processing unit 21). The object region refers to a region including a lesion such as a mammary gland distribution, a mass shape, a calcification distribution shape indicating a distribution of suspected malignancy, a line shape, a section property, or the like. The shadow of the lesion often has a characteristic density distribution. Therefore, the area specifying unit 26 specifies an area estimated as a lesion part based on such density characteristics as an object area. Since various methods have already been proposed for the algorithm for specifying the object region, detailed description thereof is omitted here. For example, as an algorithm for specifying a tumor, a method using an iris filter or the like may be used (for example, Japanese Patent Laid-Open No. 8-263364). Further, for example, as an algorithm for specifying calcification, a technique using a morphological filter or the like may be used (for example, JP-A-8-272961).

  The determination unit 25 determines an X-ray source to be driven from among a plurality of X-ray sources (electron emitting elements 35) provided in the two-dimensional NxM. In the determination of the X-ray source, first, the irradiation area of the object area corresponding to each irradiation direction is calculated based on the object area specified by the area specifying unit 26, and the irradiation area that maximizes or minimizes the irradiation area. Derive directions. Then, an X-ray source capable of irradiation from the derived irradiation direction is selected from a plurality of X-ray sources. Thereby, the X-ray source to be driven is determined. In the calculation of the irradiation area, for example, if there is a tumor in the object region, the area of the tumor is calculated. If a plurality of calcifications are gathered in the object area, the area where the plurality of calcifications gathered is approximated by a circle, and the area of the circle is calculated. This calculated value is the irradiation area. As shown in FIG. 4, the irradiation area of the object region varies depending on the irradiation direction. In FIG. 4, X-rays are irradiated only to a limited range for easy understanding, but the irradiation region is not limited to this, and may be, for example, the entire breast, For example, it may be over a wide range.

  Further, depending on the irradiation direction, as shown in FIG. 5, the mammary gland G and a lesion such as calcification C or a tumor (not shown) overlap, making it difficult to determine the lesion. Therefore, the determination unit 25 derives an irradiation direction in which an X-ray image capable of easily identifying a lesioned part such as calcification or a tumor and a mammary gland can be identified, and selects an X-ray source. For example, when the mammary gland overlaps with the lesioned part, the X-ray source may be selected by utilizing the fact that the contrast between the lesioned part and its peripheral part (within a predetermined range from the lesioned part) decreases. That is, the difference between the average pixel values of the lesioned part (that is, the object region) and the peripheral part thereof is compared, the direction in which the difference in the average pixel value is the largest is derived, and select.

  The control unit 23 controls the processing in each component of the control device 20 in an integrated manner. For example, X-ray irradiation using an X-ray source based on the determination result of the determination unit 25 is controlled. Although not shown in FIG. 3, the control unit 23 is connected to each component.

  The above is an explanation of an example of the configuration of the mammography apparatus 100, but each configuration provided in the apparatus is not necessarily realized as illustrated above. For example, each functional configuration described above may be arranged in a plurality of devices and realized as a system.

  Next, an example of the flow of imaging processing in the mammography apparatus 100 shown in FIG. 1 will be described using FIG. Here, the operation when a lesioned part is present will be described as an example.

  When this process starts, the mammography apparatus 100 first captures a first radiation image. Specifically, a plurality of X-rays are irradiated toward a subject (for example, a human body), and a plurality of X-ray images having different X-ray irradiation angles are taken (step S101). After this imaging, the mammography apparatus 100 performs reconstruction processing on a plurality of X-ray images having different X-ray irradiation angles in the image processing unit 21, and generates a plurality of tomographic images (step S102). ).

  Subsequently, the mammography apparatus 100 specifies an object region from the plurality of tomographic images generated by the image processing unit 21 in the region specifying unit 26 (step S103). As described above, the object region refers to a region where a lesion such as a mammary gland, a tumor, or calcification is imaged.

  In the mammography apparatus 100, the determination unit 25 determines an X-ray source to be driven from among a plurality of X-ray sources provided (step S104). As described above, in the determination of the X-ray source, first, the irradiation area of the object region corresponding to each irradiation direction is calculated based on the object region specified by the region specifying unit 26, and the irradiation area is maximized or The minimum irradiation direction is derived. Then, an X-ray source capable of irradiation from the derived irradiation direction is selected from a plurality of X-ray sources. Thereby, the X-ray source to be driven is determined.

  When the X-ray source to be driven is determined, mammography apparatus 100 captures a second radiation image. The second radiographic image is an image used for diagnosis, and is taken with a higher resolution and higher dose than the first radiographic image. Here, the mammography apparatus 100 captures an X-ray image while irradiating X-rays using an X-ray source based on the determination result of step S104 (step S105). The second radiographic image is captured by irradiating a larger tube current or a longer irradiation time (exposure time) X-ray than during the imaging in step S101. The length of the tube current or irradiation time at this time may be determined (automatically) based on, for example, the S / N ratio (signal / noise ratio) of the first radiation image. The lower the S / N ratio, the higher the tube current or the longer the irradiation time. In the imaging in step S101, it is not necessary to irradiate X-rays using all X-ray sources. For example, after identifying a lesion based on an X-ray image captured using a plurality (not all) of X-ray sources, a corresponding point is found between the plurality of X-ray images (tomographic images) with respect to the lesion, Based on the corresponding points, the irradiation direction in which the irradiation area is maximized or minimized is predicted. Then, an X-ray source to be driven may be determined based on the prediction result.

  In addition, although FIG. 6 demonstrated operation | movement when a lesioned part exists, when a lesioned part cannot be pinpointed in the process of step S103, X-ray | X_line using the X-ray source of a predetermined position is demonstrated. X-ray images may be taken by irradiation. Specifically, an X-ray source at a predetermined position is selected in the process of step S104, and an X-ray image is taken in the process of step S105. Examples of the X-ray source at a predetermined position include a standard position, for example, an X-ray source positioned at the center.

  As described above, according to the first embodiment, a plurality of X-ray images (first radiation images) having different X-ray irradiation angles are taken. Then, an X-ray source to be driven is determined based on the plurality of X-ray images, and X-rays are emitted using the determined X-ray source to capture an X-ray image (second radiation image). Thereby, it is possible to obtain an X-ray image that is not easily affected by the distribution of the mammary gland and is easy to diagnose the lesioned part. In addition, since the X-ray source is not mechanically moved and only needs to be switched electrically, the imaging time can be shortened. In addition, since the X-ray source does not move mechanically, it does not give fear to the patient.

(Embodiment 2)
Next, Embodiment 2 will be described. In the second embodiment, an arrangement relationship between the X-ray source of the mammography apparatus 100 and the grid 81 will be described. Note that the configuration and processing of the mammography apparatus 100 according to the second embodiment are the same as those in the first embodiment described above, and thus the description thereof is omitted.

  As shown in FIG. 7, the grid 81 is disposed between the subject M and the two-dimensional detector 12 and absorbs scattered radiation scattered by the subject M with a striped lead foil. As a result, only the X-rays that linearly pass through the subject M from the X-ray source can be selectively incident on the two-dimensional detector 12.

  Since the lead foil of the grid 81 has a structure that converges toward the point light source, if the position of the X-ray is shifted, even if it is a linear X-ray, the grid may not be transmitted (cut off) ( For example, Japanese Patent Laid-Open No. 09-066054).

  As shown in FIG. 8B, when X-ray sources (specifically, the transmission target 15) are arranged in a one-dimensional manner in a direction perpendicular to the grid stripes, direct X-rays from the X-ray source are obtained. However, it cannot be transmitted. Therefore, in the mammography apparatus 100 according to the second embodiment, the arrangement direction of the plurality of X-ray sources and the stripe direction of the grid 81 are made parallel as shown in FIG.

  As described above, according to the second embodiment, the same effects as those of the first embodiment can be obtained, and an X-ray image with less cut-off by the grid can be obtained.

(Embodiment 3)
Next, Embodiment 3 will be described. In the third embodiment, the flow of processing when photographing the left and right breasts will be described. Note that the configuration and processing of the mammography apparatus 100 according to the third embodiment are the same as those in the first embodiment described above, and thus the description thereof is omitted.

  With reference to FIG. 9, the flow of processing when photographing the left and right breasts will be described. Note that the flow of the photographing process is basically the same as the flow described in FIG. 6 of the first embodiment.

  The mammography apparatus 100 first captures a plurality of X-ray images (first radiation images) having different X-ray irradiation angles. Here, as shown in FIG. 9, for example, it is assumed that a lesioned part C such as calcification or a tumor is confirmed in the left breast. In this case, the mammography apparatus 100 irradiates X-rays from a direction that is not easily affected by the mammary gland distribution according to the procedure described in the first embodiment, and captures an X-ray image (second radiation image) of the left breast. . As described above, the second radiographic image is an image used for diagnosis, and is taken with higher resolution and higher dose than the first radiographic image.

  The other breast (right breast) is provided at a symmetrical position on the plane in which the X-ray source irradiated at the time of photographing the left breast and the X-ray sources are arranged two-dimensionally (or one-dimensionally). Imaging is performed by irradiating X-rays using an X-ray source. In this case, the X-ray irradiation direction is symmetric, and the left and right breast images are also symmetric. This facilitates comparison of the left and right breasts.

  On the other hand, when the lesioned part C is not present (the right breast shown in FIG. 9), X-rays are irradiated using a standard position, for example, an X-ray source located at the center, and imaging is performed. If there is no lesion in the other breast, the other breast is also imaged by irradiating with X-rays using an X-ray source located at the center.

  However, after imaging the right breast, when imaging the left breast with a lesion, X-rays are applied to the left breast from a direction that is less susceptible to mammary gland distribution according to the procedure described in the first embodiment. Irradiate and take an X-ray image. Here, when comparing the X-ray image of the right breast without the lesioned portion taken earlier with the left breast with the lesioned portion taken later, if the symmetry is significantly different, the previous portion is taken again. Take a picture of the right breast. For example, the areas of the breast portions of the left and right images are compared, and if the difference is greater than or equal to a certain value, imaging may be performed again.

  As described above, according to the third embodiment, the same effects as those of the first embodiment can be obtained, and an X-ray image that can be easily subjected to comparative interpretation of the left and right breasts can be obtained.

(Embodiment 4)
Next, Embodiment 4 will be described. In the fourth embodiment, a mammography apparatus 100 having a puncture aspiration cytology function will be described. Specifically, when calcifications, etc., showing the distribution of suspicion of malignancy, linearity, area, etc. are found, it is necessary to judge whether it is benign or malignant. In such a case, puncture aspiration cytology is performed. In puncture aspiration cytology, an aspiration needle (biopsy needle) is inserted into the breast, and tissues suspected of malignant lesions including calcification are collected. Note that the configuration and processing of the mammography apparatus 100 according to the fourth embodiment are basically the same as those of the first embodiment described above, and therefore, differences will be described here with emphasis.

  FIG. 10 is a diagram illustrating an example of a functional configuration of the control device 20 according to the fourth embodiment.

  The control device 20 has, as its functional configuration, an image processing unit 21, an image display unit 22, a control unit 23, an operation unit 24, a determination unit 25, a region specification unit 26, and an insertion direction determination unit 72. And a biopsy needle control unit 73. Note that the imaging apparatus 10 is provided with a biopsy needle moving unit 74 and a biopsy needle 75 as new configurations.

  The operation unit 24 functions as an area designating unit for the operator to designate an area for collecting a lesion from the breast. The operation unit 24 is realized by a mouse, a keyboard, or the like, for example. The image display unit 22 and the operation unit 24 may be realized by a touch panel integrated with each other.

  The insertion direction determination unit 72 determines the insertion direction (insertion angle) of the biopsy needle 75 with respect to the lesion area designated through the operation unit 24. The insertion direction is determined in a direction that is likely to collect more lesions. The direction is determined based on the density characteristics of a plurality of tomographic images generated by the image processing unit 21. For example, when there are a plurality of calcifications, the direction passing through the center of gravity of each of the plurality of calcifications is determined as the insertion direction based on the plurality of tomographic images. In addition to this, the insertion direction of the biopsy needle 75 may be a direction in which a large blood vessel does not enter the insertion path of the biopsy needle 75, for example.

  The biopsy needle moving unit 74 moves the biopsy needle 75. The biopsy needle control unit 73 controls the biopsy needle 75. Specifically, the biopsy needle moving unit 74 is controlled based on the insertion direction determined by the insertion direction determining unit 72. Thereby, the position and insertion angle of the biopsy needle 75 are controlled, and the biopsy needle 75 is inserted into the lesioned part.

  Here, the flow of the puncture aspiration cytodiagnosis process will be briefly described.

  When the lesioned part C is found, the operator fixes the patient's breast with the compression plate 13 so that the lesioned part C comes to the center of the two-dimensional detector 12 with reference to the breast image taken in advance. After fixing the breast, the mammography apparatus 100 performs imaging by irradiating X-rays from various angles. The mammography apparatus 100 displays this captured image on the image display unit 22. Note that the image displayed here may be a one-dimensional image or a tomographic image.

  The operator operates the operation unit 24 while referring to the plurality of displayed images, and designates the region of the lesioned part C. In accordance with this instruction, the mammography apparatus 100 determines the insertion direction (insertion angle) of the biopsy needle 75 in the insertion direction determination unit 72. The insertion direction is performed based on density characteristics of a plurality of tomographic images generated by the image processing unit 21. Then, the mammography apparatus 100 controls the position and insertion angle of the biopsy needle 75 based on the determined insertion direction in the biopsy needle control unit 73. Thereby, the biopsy needle 75 is inserted into the lesioned part C.

  In the above description, the case where the operator gives an instruction for an area to collect a lesion from the breast via the operation unit 24 is described as an example, but the present invention is not limited to this. For example, a three-dimensional position calculation unit is provided, and the three-dimensional positions of the X-axis, Y-axis, and Z-axis of the lesion are automatically calculated based on the object region specified by the region specifying unit 26, and the calculation result is Based on this, it may be possible to automatically collect the lesioned part.

  As described above, according to the fourth embodiment, the same effects as those of the first embodiment can be obtained, and the insertion direction and position of the biopsy needle 75 are determined based on a plurality of tomographic images and the like, and the biopsy needle 75 is inserted. Thereby, puncture aspiration cytodiagnosis can be performed without putting a big burden on a patient.

  The above is an example of a typical embodiment of the present invention, but the present invention is not limited to the embodiment described above and shown in the drawings, and can be appropriately modified and implemented without departing from the scope of the present invention. .

  It should be noted that the present invention can take the form of, for example, a system, apparatus, method, program, or recording medium. Specifically, the present invention may be applied to a system composed of a plurality of devices, or may be applied to an apparatus composed of a single device.

  Moreover, you may comprise so that the process mentioned above may be implemented by the program installed in the computer. This program can be provided not only by a communication means such as a network but also by storing it in a recording medium such as a CD-ROM.

Claims (11)

A radiographic apparatus for taking radiographic images,
Radiation generating means for irradiating a subject with a plurality of radiation generated using a plurality of radiation generating sources arranged in a one-dimensional manner ;
Radiation detecting means for capturing a plurality of first radiation images based on detection of a plurality of radiations having different irradiation angles transmitted through the subject;
Selecting means for selecting, from among the plurality of radiation generation sources, a radiation generation source for irradiating the object region identified based on the plurality of first radiation images;
A grid that is disposed between the subject and the radiation detection means and absorbs scattered radiation scattered by the subject,
The radiation imaging apparatus , wherein an array direction of the plurality of radiation sources arranged in a one-dimensional manner and a stripe direction of the grid are parallel . Image processing means for performing reconstruction processing on the plurality of first radiation images to generate a plurality of tomographic images;
The radiographic apparatus according to claim 1, further comprising: an area specifying unit that specifies the object area based on a plurality of tomographic images generated by the image processing unit.   The selection means calculates an irradiation area of the object area corresponding to each irradiation direction based on the object area specified by the area specifying means, and selects a radiation source that should generate radiation based on the irradiation area. The radiation imaging apparatus according to claim 2, wherein the radiation imaging apparatus is determined.   The radiation imaging apparatus according to claim 3, wherein the selection unit selects a radiation source capable of emitting radiation from an irradiation direction in which the irradiation area is maximized or minimized.   The selection means compares the difference in average pixel values between the object area specified by the area specifying means and an area within a predetermined range from the object area, and from the direction in which the difference in average pixel value is the largest. The radiation imaging apparatus according to claim 2 or 3, wherein a radiation source capable of emitting radiation is selected. The grid, radiation imaging apparatus according to any one of claims 1 to 5 scattered radiation scattered by the object, wherein the benzalkonium be absorbed by striped lead foil. The subject is a breast;
7. The selection means according to claim 1, wherein when selecting a radiation source for one breast, the radiation source is provided at a position symmetrical to the radiation source selected at the time of imaging the other breast. The radiation imaging apparatus according to any one of the above. The subject is a breast;
An insertion direction determining means for determining a direction in which a biopsy needle is inserted based on a plurality of first radiation images photographed by the radiation detecting means;
The biopsy needle control means for controlling the insertion of the biopsy needle into the breast in the direction determined by the insertion direction determination means, further comprising: The radiation imaging apparatus described.   The second radiographic image captured using the radiation source selected by the selection means is performed with a larger tube current or longer irradiation time than when the first radiographic image is captured. The radiation imaging apparatus according to any one of claims 1 to 8. The subject is a breast;
The radiographic apparatus according to claim 1, wherein the object region includes at least one of a mammary distribution, a mass shape, and a calcification distribution. A method for controlling a radiation imaging apparatus that captures a radiation image,
Irradiating a subject with a plurality of radiation generated using a plurality of radiation generation sources arranged in a one-dimensional manner ;
Capturing a plurality of first radiation images by detecting a plurality of radiations having different irradiation angles transmitted through the subject using radiation detection means ;
Have a, and selecting from among the radiation sources of the plurality of radiation sources for irradiating the object area specified based on the plurality of first radiographic image,
A grid that absorbs scattered radiation scattered by the subject, the subject and the radiation detection means, so that the arrangement direction of the plurality of radiation sources arranged in a one-dimensional manner and the stripe direction of the grid are parallel to each other. the method of the radiation imaging apparatus according to claim that you have placed between the.

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