WO2012120886A1

WO2012120886A1 - Three-dimensional radiographic apparatus and method

Info

Publication number: WO2012120886A1
Application number: PCT/JP2012/001584
Authority: WO
Inventors: 孝夫桑原; 大田　恭義; 靖子八尋; 玲長谷川
Original assignee: 富士フイルム株式会社
Priority date: 2011-03-10
Filing date: 2012-03-08
Publication date: 2012-09-13

Abstract

[Problem] To minimize patient exposure in a three-dimensional radiographic apparatus, wherein the exposure dose in one of two imaging directions is smaller than the exposure dose in the other imaging direction, while ensuring the quality of radiographic images in the one imaging direction. [Solution] A three-dimensional radiographic apparatus, which captures images by exposing a subject to radiation at a predetermined radiation exposure dose in one imaging direction, and a radiation exposure dose in the other imaging direction, which is less than the one exposure dose, wherein an imaging condition setting unit (2b) sets both exposure doses, and a monitor (3) displays both exposure doses set by the imaging condition setting unit (2b) when the subject undergoes imaging.

Description

Three-dimensional radiography apparatus and method

The present invention relates to a three-dimensional radiography apparatus and method for irradiating a subject with radiation from two different imaging directions. More specifically, of the two shooting directions, the subject is irradiated with radiation having a predetermined irradiation dose from one shooting direction, and the subject is irradiated with radiation having an irradiation dose smaller than the irradiation dose in the one shooting direction from the other shooting direction. The present invention relates to a three-dimensional radiography apparatus and method.

In recent years, in order to make diagnosis easier, three-dimensional radiography that captures stereoscopically visible radiographic images by irradiating a subject from two different radiographing directions and acquiring two radiographic images with parallax from each other It has been known.

In such 3D radiography, the number of radiation exposures is increased as compared to 2D radiography in which a radiographic image of a subject is viewed in plan view, so it is important to suppress the exposure dose of the patient. Patent Document 1 proposes a technique for displaying a warning when a set condition exceeds a maximum tube current product value.

By the way, in order to perform stereoscopic viewing using two radiographic images having parallax, it is not always necessary that both radiographic images have the same sharpness, a reference image in which one radiographic image is clearly captured, the other The radiographic image may be a reference image taken with a lower irradiation dose than the standard image. Thereby, stereoscopic vision is possible and the exposure dose of the patient can be suppressed.

Patent Document 2 proposes a technique for reducing an irradiation dose in capturing a radiographic image visually recognized by a person other than the dominant eye based on the dominant eye information of the observer to be smaller than an irradiation dose in capturing a radiographic image visually recognized by the dominant eye. Yes.

JP 2010-234003 A JP 2010-187735 A

However, in the three-dimensional radiography as described above, if the irradiation dose in one imaging direction is lowered in order to suppress the exposure dose of the patient, the irradiation dose in the other imaging direction is further reduced. As a result, the amount of radiation detected in the radiation emitted from the other imaging direction is reduced, and the image quality of the other radiation image may be degraded.

In view of the above circumstances, the object of the present invention is to reduce the exposure dose of a patient and reduce the image quality of the other radiation image in three-dimensional radiography in which the irradiation dose in the other imaging direction is smaller than the irradiation dose in one imaging direction. A three-dimensional radiation imaging apparatus and method that can be secured are provided.

In order to solve the above problems, the three-dimensional radiographic apparatus of the present invention is a radiation having a predetermined irradiation dose (hereinafter referred to as one irradiation dose) from one of the two different imaging directions. Imaging in which both irradiation doses are set in a three-dimensional radiography apparatus that irradiates a subject with radiation having an irradiation dose smaller than one irradiation dose (hereinafter referred to as the other irradiation dose) from the other imaging direction. The image processing apparatus includes a condition setting unit and a display unit that displays both irradiation doses set by the imaging condition setting unit when the subject is imaged.

In the three-dimensional radiography method of the present invention, of two different imaging directions, radiation of a predetermined irradiation dose (hereinafter referred to as one irradiation dose) from one imaging direction, and one irradiation dose from the other imaging direction. In the three-dimensional radiography method in which a subject is irradiated with a smaller amount of radiation (hereinafter referred to as the other radiation dose), and both of the radiation doses are set and the subject is captured. Both irradiation doses are displayed.

In the three-dimensional radiography apparatus of the present invention, the imaging condition setting unit may set the other irradiation dose based on the one irradiation dose, and the imaging condition setting unit may set the one irradiation dose to the other irradiation dose. The other irradiation dose may be set by multiplying a predetermined coefficient.

Further, the three-dimensional radiography apparatus of the present invention includes a breast thickness acquisition unit that acquires information about the breast thickness, and the imaging condition setting unit applies an irradiation dose based on the information about the breast thickness. It may be set so as to increase.

Here, “information on breast thickness” in the three-dimensional radiography apparatus of the present invention does not mean only breast thickness information, but information that can calculate breast thickness, for example, compression that compresses the breast. It means to include the position information of the board.

In the three-dimensional radiographic apparatus of the present invention, the display unit may display an upper limit value and / or a lower limit value of the irradiation dose, and / or when one irradiation dose exceeds the upper limit value and / or the other. A warning may be displayed when the irradiation dose is less than the lower limit.

The three-dimensional radiation imaging apparatus of the present invention includes a radiation detector that detects radiation passing through a subject, and an intermediate direction between one imaging direction and the other imaging direction is relative to a detection surface of the radiation detector. It may intersect with a vertical direction. In the three-dimensional radiation imaging apparatus of the present invention, one imaging direction may be a direction perpendicular to the detection surface. In the three-dimensional radiographic apparatus of the present invention, the angle formed by one imaging direction and the other imaging direction may be in the range of 2 ° to 5 °.

According to the three-dimensional radiography apparatus and method of the present invention, of two mutually different imaging directions, radiation having a predetermined irradiation dose from one imaging direction and irradiation dose less than one irradiation dose from the other imaging direction. In 3D radiography, where each subject is irradiated with radiation, both exposure doses are set, and when the subject is shot, the photographer displays both of the set exposure doses. Therefore, it is possible to estimate whether or not the exposure dose of the other radiation image is too small, and thus it is possible to secure the image quality of the other radiation image while suppressing the exposure dose of the patient.

Schematic configuration diagram of three-dimensional radiography apparatus Front view of a part of the 3D camera body The block diagram which shows the structure of the computer in 1st Embodiment. Diagram showing the display of irradiation dose, upper limit and lower limit (Part 1) Diagram showing the display of irradiation dose, upper limit and lower limit (Part 2) Diagram showing the display of irradiation dose, upper limit and lower limit (Part 3) The figure which shows the display of irradiation dose, an upper limit, and a lower limit (the 4) The flowchart which shows the effect | action in 1st Embodiment. Block diagram showing a configuration of a computer according to the second embodiment Flowchart showing the operation in the second embodiment (part 1) Flowchart showing the operation in the second embodiment (part 2)

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a first embodiment of a three-dimensional radiation imaging apparatus of the present invention. As shown in FIG. 1, the three-dimensional radiation imaging apparatus 100 includes a three-dimensional imaging apparatus main body 1, a computer 2 connected to the three-dimensional imaging apparatus main body 1, a monitor 3 connected to the computer 2, and an input unit 4. ing. FIG. 2 is a partial front view of the three-dimensional imaging apparatus main body 1.

The three-dimensional radiography apparatus 100 irradiates the breast M, which is a subject, from two different imaging directions D1 and D2 (see FIG. 2) of the three-dimensional imaging apparatus main body 1 to produce two radiographic images having parallax. The radiographic image of the breast M is displayed in a three-dimensional manner using the two radiographic images captured and captured by the monitor 3.

First, the 3D imaging apparatus main body 1 will be described. The three-dimensional imaging apparatus main body 1 shoots a reference image by irradiating the breast M with radiation from the imaging direction D1 and irradiating the breast M with radiation from the imaging direction D2. Further, the radiation dose irradiated from the imaging direction D2 is smaller than the radiation dose of the radiation irradiated from the imaging direction D1.

As shown in FIG. 1, the three-dimensional imaging apparatus main body 1 includes a base 11, a rotary shaft 12 that can move in the vertical direction (Z direction) with respect to the base 11, and can rotate. The arm part 13 connected with the base 11 is provided.

The arm section 13 has an alphabet C shape, and a radiation table 16 is attached to one end of the arm section 13 so as to face the imaging table 14 at the other end. The rotation and vertical movement of the arm unit 13 are controlled by an arm controller 31 incorporated in the base 11.

Inside the imaging table 14 are provided a radiation detector 15 such as a flat panel detector and a detector controller 33 that controls reading of charge signals from the radiation detector 15. The imaging table 14 includes a charge amplifier that converts the charge signal read from the radiation detector 15 into a voltage signal, a correlated double sampling circuit that samples the voltage signal output from the charge amplifier, a voltage A circuit board such as an AD conversion circuit for converting a signal into a digital signal is installed.

In addition, the imaging table 14 is configured to be rotatable with respect to the arm unit 13, and even when the arm unit 13 rotates with respect to the base 11, the direction of the imaging table 14 is fixed to the base 11. can do.

The radiation detector 15 detects radiation applied to the detection surface 15a through the breast M. The radiation detector 15 may be a so-called direct-type radiation image detector that directly receives radiation and generates charges, or once converts radiation into visible light and converts the visible light into a charge signal. A so-called indirect radiation image detector may be used. The radiation detector 15 includes a scattered radiation absorption grid 15b integrated with the radiation detector 15 on the detection surface 15a. The scattered radiation absorption grid 15b removes scattered radiation scattered by the breast M.

As a radiation image signal readout method, a radiation image signal is read out by turning on and off a TFT (thin film transistor) switch, or a radiation image is emitted by irradiating reading light. It is desirable to use a so-called optical readout system in which a signal is read out, but the present invention is not limited to this, and other systems may be used.

A radiation source 17 and a radiation source controller 32 are housed inside the radiation irradiation unit 16. The radiation source controller 32 controls the timing of irradiating radiation from the radiation source 17, and the irradiation conditions of the radiation source 17, that is, the tube current (mA), the irradiation time (ms), and the tube voltage (kV).

Further, in the central portion of the arm portion 13, a compression plate 18 that is disposed above the imaging table 14 and presses and compresses the breast M, a support portion 20 that supports the compression plate 18, and a support portion 20 that extends in the vertical direction. A moving mechanism 19 for moving in the (Z direction) is provided. The position of the compression plate 18 and the compression pressure are controlled by the compression plate controller 34.

Next, the computer 2 will be described. FIG. 3 is a block diagram showing a schematic configuration of the computer 2. The computer 2 includes a central processing unit (CPU) and a storage device such as a semiconductor memory, a hard disk, and an SSD, and the control unit 2a, the imaging condition setting unit 2b, the radiation shown in FIG. It comprises an image storage unit 2c, a dose display control unit 2d, and an image display control unit 2e.

The control unit 2a controls the controllers 31 to 34 by outputting predetermined control signals to the various controllers 31 to 34. The shooting condition setting unit 2b sets shooting conditions. The radiographic image storage unit 2c stores radiographic image signals in the imaging directions D1 and D2 read from the radiation detector 15, respectively.

The dose display control unit 2d displays radiation doses (mAs) in the imaging directions D1 and D2 on the monitor 3 when performing radiography. The image display control unit 2e performs predetermined processing on the two radiographic images to display the radiographic image of the breast M on the monitor 3 in a three-dimensional manner. Details of the imaging condition setting unit 2b and the dose display control unit 2d will be described later.

The monitor 3 corresponds to a display unit in claims, and displays radiation doses in the imaging directions D1 and D2 two-dimensionally at the time of radiography of the breast M, and uses the captured standard image and reference image. The radiation image of the breast M is configured to be displayed three-dimensionally.

As a configuration for three-dimensional display, for example, radiographic images based on two radiographic image signals are displayed using two screens, and a reference image is displayed on the right eye of the observer by using a half mirror, polarizing glass, or the like. It is possible to adopt a configuration in which a three-dimensional image is displayed by making the reference image incident on the left eye of the observer. The base image may be incident on the left eye and the reference image on the right eye.

In addition, for example, two radiographic images may be displayed in a superimposed manner while being shifted by a predetermined amount of parallax, and this may be displayed three-dimensionally by observing with a polarizing glass, or a parallax barrier method and a lenticular method. As described above, the standard image and the reference image may be displayed on a 3D liquid crystal that can be viewed stereoscopically to display three-dimensionally.

Next, the input unit 4 will be described. The input unit 4 includes, for example, a keyboard, a mouse, a touch panel, and various switches, and accepts input of shooting conditions for each shooting direction, input of a shooting start instruction, and the like by a photographer. Imaging conditions include imaging angle θ, tube current (mA), irradiation time (sec), upper and lower limits of irradiation dose, tube voltage (kV), target type, filter type and focus size (μm). included.

The photographing angle θ is an angle formed by a direction V (see FIG. 2) perpendicular to the detection surface 15a and the photographing directions D1 and D2. The combination of the shooting angles θ in the shooting directions D1 and D2 is not particularly limited, but in this embodiment, the shooting angle θ in the shooting direction D1 is 0 ° and the shooting angle θ in the shooting direction D2 is 4 °. The photographing angle θ may be a negative value when the clockwise direction is positive (see FIG. 2).

The shooting angle θ in the shooting direction D1 is preferably smaller than the shooting angle θ in the shooting direction D2 so that the reference image can be easily viewed, that is, an intermediate direction D3 between the shooting direction D1 and the shooting direction D2 (FIG. 2). It is desirable that the reference) intersects the vertical direction V. In order to use the reference image as a radiographic image by two-dimensional radiography, it is desirable that the imaging angle θ in the imaging direction D1 is 0 °, that is, the imaging direction D1 is orthogonal to the detection surface 15a. Further, in order to enable stereoscopic viewing, it is desirable that the angle formed by the shooting direction D1 and the shooting direction D2 is in the range of 2 ° to 5 °.

The tube current (mA) and the irradiation time (sec) are for adjusting the radiation dose (mAs) which is a tube current product. In the following description, the tube current product is described as an irradiation dose (mAs). The input unit 4 may accept a direct input of irradiation dose (mAs). The upper limit value of the irradiation dose (mAs) is for suppressing the exposure dose of the breast M, and the lower limit value is for ensuring the image quality of the radiation image.

The tube voltage (kv) adjusts the radiation quality of the radiation. By reducing the tube voltage (kv), the radiation becomes soft and the shadow of the breast M can be easily expressed. The type of the target and the filter adjusts the spectral distribution of radiation, and is selected from molybdenum (Mo), rhodium (Rh), and aluminum (Al). The focus size adjusts the sharpness of the radiographic image, and the resolution of the radiographic image is improved by reducing the focus size.

The photographing condition setting unit 2b will be described in detail. The imaging condition setting unit 2b receives imaging conditions from the input unit 4, and sets the irradiation dose (mAs) in the imaging directions D1 and D2 based on the received imaging conditions. The imaging condition setting unit 2b multiplies the tube current product (mA) by the irradiation time (sec) to set the irradiation dose (mAs) in the imaging direction D1, and sets the irradiation dose (mAs) in the imaging direction D1 to 0. Multiply by a predetermined coefficient of about 5 to 0.7 to set the irradiation dose (mAs) in the imaging direction D2. The coefficient can be arbitrarily changed by the photographer via the input unit 4. When the input unit 4 directly receives the irradiation dose (mAs) in the imaging direction D1, the imaging condition setting unit 2b sets the received value as the irradiation dose (mAs) in the imaging direction D1.

The imaging condition setting unit 2b sets a combination of the tube current (mA) and the irradiation time (sec) in the imaging direction D2 that satisfies the irradiation dose (mAs) in the imaging directions D1 and D2 and the irradiation dose (mAs) in the imaging direction D2. To do. The imaging condition setting unit 2b divides the value obtained by dividing the tube current (mA) in the imaging direction D1 and the irradiation dose (mAs) in the imaging direction D2 by the tube current (mA) in the imaging direction D1. ), May be set as the irradiation time (sec), and the value obtained by dividing the irradiation time (sec) in the imaging direction D1 and the irradiation dose (mAs) in the imaging direction D2 by the irradiation time (msec) in the imaging direction D1 The irradiation time (sec) in the direction D2 and the tube current (mA) may be set.

The dose display control unit 2d is for causing the monitor 3 to display the irradiation dose, the upper limit value, and the lower limit value in the imaging directions D1 and D2 before the 3D imaging apparatus body 1 performs radiography of the breast M. FIG. 4 is a diagram illustrating an example of display of the irradiation dose (mAs), the upper limit value, and the lower limit value. The dose display control unit 2d displays a warning when the irradiation dose (mAs) exceeds the upper limit value and / or less than the lower limit value. 5, 6 and 7 are diagrams showing examples of display of irradiation dose accompanied by a warning, upper limit value and lower limit value. The dose display control unit 2d may display the upper limit value or the lower limit value on the monitor 3.

The dose display control unit 2d displays a confirmation button that allows the photographer to confirm the irradiation dose as shown in FIGS. 4 to 6, the coefficient for calculating the irradiation dose (mAs) in the imaging direction D2 is 0.7, and in FIG. 7, it is 0.6.

A series of operations of the three-dimensional radiation imaging apparatus 100 will be described. FIG. 8 is a flowchart showing the operation of the first embodiment. First, the breast M is installed, and the input unit 4 receives the respective imaging conditions in the imaging directions D1 and D2 (ST1). The imaging condition setting unit 2b receives the imaging conditions in the imaging directions D1 and D2 (ST2), calculates the irradiation dose (mAs) in the imaging directions D1 and D2 (ST3), and sets each imaging condition (ST4). .

Wait until the input unit 4 receives an instruction to start shooting (ST5). When the input unit 4 receives an instruction to start imaging, the control unit 2 a outputs a control signal for compressing the breast M to the compression plate controller 34. The compression plate controller 34 receives the control signal and compresses the breast M with a predetermined pressure (ST6).

The dose display control unit 2d reads the irradiation dose (mAs), the upper limit value, and the lower limit value in the imaging directions D1 and D2 from the imaging condition setting unit 2b and displays them on the monitor 3 (ST7). Further, the dose display control unit 2d determines whether or not the irradiation dose (mAs) in the imaging directions D1 and D2 exceeds the upper limit value (ST8), and displays a warning on the monitor 3 if the upper limit value is exceeded. (ST9). Wait until the photographer confirms the warning, and after confirming the warning, the process returns to accepting the photographing conditions (ST1).

When the irradiation doses in the imaging directions D1 and D2 are less than or equal to the upper limit value, the imaging condition setting unit 2b determines whether or not the irradiation doses (mAs) in the imaging directions D1 and D2 are less than the lower limit value (ST10). If it is less than the value, a warning is displayed on the monitor 3 (ST9). Wait until the photographer confirms the warning, and after confirming the warning, the process returns to accepting the photographing conditions (ST1).

When the exposure dose in the imaging directions D1 and D2 is equal to or higher than the lower limit value, imaging of the reference image starts. First, the control unit 2a reads the shooting angle θ = 0 ° in the shooting direction D1 from the shooting condition setting unit 2b, and outputs a control signal for rotating the arm unit 13 to the arm controller 31. The arm controller 31 receives the control signal, and rotates the arm unit 13 so that the photographing direction D1 is perpendicular to the detection surface 15a.

When the arm unit 13 is in the posture P1 (see FIG. 2) perpendicular to the detection surface 15a, the control unit 2a sends the tube voltage (kv), the tube current (mA) in the photographing direction D1, and the irradiation from the photographing condition setting unit 2b. Each time (sec) is read out and a control signal for irradiating the radiation source controller 31 with radiation from the radiation source 17 is output. The radiation source controller 32 receives the control signal and emits radiation from the radiation source 17.

The control unit 2a outputs a control signal to the detector controller 33 so as to read out the radiation image signal. The detector controller 33 receives the control signal and reads the radiation image signal from the radiation detector 15 that has detected the radiation. The radiographic image storage unit 2c stores the radiographic image signal in the imaging direction D1, and the imaging of the reference image ends (ST11).

Next, the control unit 2a reads the shooting angle θ = 4 ° in the shooting direction D2 from the shooting condition setting unit 2b and outputs a control signal for rotating the arm unit 13 to the arm controller 31. The arm controller 31 receives the control signal and rotates the arm unit 13 so that the photographing direction D2 is inclined by 4 ° with respect to the direction V perpendicular to the detection surface 15a.

When the arm unit 13 is in a posture P2 (see FIG. 2) inclined by 4 ° with respect to the direction V perpendicular to the detection surface 15a, the control unit 2a receives the tube voltage (kv) and the shooting direction D2 from the shooting condition setting unit 2b. The tube current (mA) and the irradiation time (sec) are read out, and a control signal for causing the radiation source controller 32 to irradiate radiation from the radiation source 17 is output. The radiation source controller 32 receives the control signal and emits radiation from the radiation source 17.

The control unit 2a outputs a control signal to the detector controller 33 so as to read out the radiation image signal. The detector controller 33 receives the control signal and reads the radiation image signal from the radiation detector 15 that has detected the radiation. The radiographic image storage unit 2c stores the radiographic image signal in the imaging direction D2, and the imaging of the reference image ends (ST12).

The image display control unit 2e reads out the radiographic image signals in the imaging directions D1 and D2 from the radiographic image storage unit 2c and performs predetermined pixel processing, and then displays the reference image and the reference image on the monitor 3, respectively. Then, the radiation image of the breast M is displayed three-dimensionally and the process is terminated (ST13).

Next, a second embodiment of the three-dimensional imaging device will be described. In the second embodiment, the irradiation dose (mAs) is set to be increased based on information on the thickness of the breast M. In general, when the compressed breast M is thick, the amount of radiation absorbed by the breast M increases, so that the amount of detected radiation tends to decrease. As a result, particularly when the reference image is captured, there is a possibility that the amount of detected radiation is reduced and the image quality of the reference image cannot be guaranteed.

Therefore, in the second embodiment, as shown in FIG. 9, the computer 2 includes a breast thickness acquisition unit 2 f that acquires information related to the thickness of the breast M, and the imaging condition setting unit 2 b It differs from the first embodiment in that the irradiation dose (mAs) is set based on the information on the thickness. Therefore, in the second embodiment, only differences from the first embodiment will be described, and the same configurations and operations as those in the first embodiment will be denoted by the same reference numerals and description thereof will be omitted. To do.

The breast thickness acquisition unit 2 f acquires information on the thickness of the breast M from the compression plate controller 34. Here, the information regarding the thickness of the breast M is not limited to the thickness information of the breast M, but is information that allows the thickness of the breast M to be calculated. Specifically, the breast thickness acquisition unit 2 f acquires position information of the compression plate 18 after the breast M is compressed.

When the imaging condition setting unit 2b receives positional information of the compression plate 18 after compression from the breast thickness acquisition unit 2f and determines that the thickness of the breast M exceeds a predetermined threshold, the irradiation doses in the imaging directions D1 and D2 ( (mAs) is multiplied by a coefficient of about 1.1 to 1.3 to set a large amount of irradiation dose (mAs) in the imaging directions D1 and D2.

At this time, the imaging condition setting unit 2b sets many irradiation doses (mAs) so that the irradiation dose (mAs) does not exceed the upper limit value. Further, the imaging condition setting unit 2b may set a large amount of irradiation dose (mAs) set in the imaging direction D2. The coefficient can be changed by the photographer via the input unit 4.

When the imaging condition setting unit 2b sets many irradiation doses (mAs) in the imaging directions D1 and D2, the tube current (mA) in the imaging directions D1 and D2 so as to satisfy the irradiation doses (mAs) in the imaging directions D1 and D2. Also reset the irradiation time (sec).

A series of processes of the three-dimensional radiation imaging apparatus 100 in the second embodiment will be described. FIG. 10 and FIG. 11 are flowcharts showing a series of processes of the three-dimensional radiation imaging apparatus 100 in the second embodiment. The same processes (ST1) to (ST6) as in the first embodiment are performed.

When the breast M is compressed, the breast thickness acquisition unit 2f acquires positional information of the compression plate 18 from the compression plate controller 34 (ST14), and whether the imaging condition setting unit 2b exceeds the predetermined threshold value. It is determined whether or not (ST15). When the thickness of the breast M is equal to or smaller than the predetermined threshold value, each process (ST7 to ST13) is performed as in the first embodiment. When the thickness of the breast M exceeds a predetermined threshold, the imaging condition setting unit 2b sets a large amount of each irradiation dose in the imaging directions D1 and D2 so as not to exceed the upper limit (ST16). At this time, the irradiation dose (mAs), tube current (mA), and irradiation time (sec) in the imaging directions D1 and D2 are reset. Then, the same processes (ST7) to (ST13) as in the first embodiment are performed.

According to the above embodiment, when the imaging condition setting unit 2b sets the irradiation dose (mAs) in the imaging directions D1 and D2, and the breast M is imaged, the monitor 3 applies the irradiation dose (mAs) in the imaging directions D1 and D2. Since the photographer can estimate the exposure dose of the breast M and confirm the irradiation dose (mAs) in the imaging direction D2, the image quality of the reference image can be ensured while suppressing the exposure dose of the breast M.

Further, according to the above embodiment, even when the imaging condition setting unit 2b sets the irradiation dose (mAs) in the imaging direction D2 based on the irradiation dose (mAs) in the imaging direction D1, the imaging direction D2 Therefore, it is possible to ensure the image quality of the reference image while suppressing the exposure dose of the breast M.

Further, according to the above-described embodiment, the image display control unit 2e acquires the positional information of the compression plate 18 after compression, and the imaging condition setting unit 2b acquires the imaging direction based on the positional information of the compression plate 18 after compression. By setting the irradiation doses (mAs) of D1 and D2 to be large, the image quality of the reference image is reliably suppressed while suppressing the exposure dose of the breast M even if the breast M is thick and the radiation absorbed is large. Can be secured.

According to the above embodiment, since the monitor 3 displays the upper limit value and the lower limit value of the irradiation dose (mAs), the photographer can set the irradiation dose (mAs) in the shooting directions D1 and D2 within a predetermined range. Since it can be confirmed, the image quality of the reference image can be ensured while reliably reducing the exposure dose of the breast M. Furthermore, according to the above-described embodiment, when the irradiation dose (mAs) in the imaging direction D1 exceeds the upper limit value and / or when the irradiation dose (mAs) in the imaging direction D2 is less than the lower limit value, the monitor 3 displays a warning. Therefore, the image quality of the reference image can be ensured while more reliably suppressing the exposure dose of the breast M.

Further, according to the above-described embodiment, since the intermediate direction D3 between the shooting direction D1 and the shooting direction D2 intersects the direction V perpendicular to the detection surface 15a, it is possible to take a reference image that is easy to see. Further, according to the above embodiment, since the imaging direction D1 is a direction perpendicular to the detection surface 15a, the reference image can be used as an image captured by a two-dimensional radiation image. Further, according to the above-described embodiment, since the angle formed by the photographing direction D1 and the photographing direction D2 is 2 ° to 5 °, the three-dimensional display of the breast M that can be stereoscopically viewed using the standard image and the reference image is possible. it can.

Claims

Three-dimensional radiation that is shot by irradiating a subject with radiation having a predetermined irradiation dose from one of the two different shooting directions, and radiation with an irradiation dose smaller than the first irradiation dose from the other shooting direction. In the shooting device,
An imaging condition setting unit for setting both irradiation doses,
A three-dimensional radiation imaging apparatus comprising: a display unit configured to display both irradiation doses set by the imaging condition setting unit when imaging the subject.
The three-dimensional radiography apparatus according to claim 1, wherein the imaging condition setting unit sets the other irradiation dose based on the one irradiation dose.
3. The three-dimensional radiography apparatus according to claim 1, wherein the imaging condition setting unit sets the other irradiation dose by multiplying the one irradiation dose by a predetermined coefficient.
The subject is a breast, and includes a breast thickness acquisition unit that acquires information on the thickness of the breast,
The three-dimensional radiography apparatus according to any one of claims 1 to 3, wherein the imaging condition setting unit sets the irradiation dose to be increased based on information on the thickness of the breast.
The three-dimensional radiation imaging apparatus according to any one of claims 1 to 4, wherein the display unit displays an upper limit value and / or a lower limit value of the irradiation dose.
The three-dimensional display according to claim 5, wherein the display unit displays a warning when the one irradiation dose exceeds the upper limit value and / or when the other irradiation dose is less than the lower limit value. Radiography equipment.
A radiation detector for detecting radiation passing through the subject;
The intermediate direction between the one imaging direction and the other imaging direction intersects a direction perpendicular to the detection surface of the radiation detector. 3D radiography equipment.
The three-dimensional radiation imaging apparatus according to any one of claims 1 to 7, wherein the one imaging direction is a direction perpendicular to the detection surface.
The three-dimensional radiographic apparatus according to any one of claims 1 to 8, wherein an angle formed by the one imaging direction and the other imaging direction is in a range of 2 ° to 5 °.
Three-dimensional radiation that is shot by irradiating a subject with radiation having a predetermined irradiation dose from one of the two different shooting directions, and radiation with an irradiation dose smaller than the first irradiation dose from the other shooting direction. In the shooting method,
Set both said doses,
A three-dimensional radiography method, wherein both of the set irradiation doses are displayed when the subject is imaged.