JP2023122538A - X-ray imaging apparatus and imaging position correction method - Google Patents

Abstract

To provide an X-ray imaging apparatus capable of acquiring an X-ray image that allows diagnosis to be executed accurately while suppressing an increase in an exposure dose and an imaging time.SOLUTION: An X-ray imaging apparatus (100) includes: an X-ray irradiation unit (1); an X-ray detection unit (2); and a correction information acquisition unit (processing unit 81) for specifying each outer edge of a plurality predetermined parts in one imaging object of a subject (201) in an X-ray image and acquiring position correction information for correcting a relative position of the X-ray irradiation unit (1) with respect to the imaging object of the subject (201) on the basis of position relations between the specified outer edges of the plurality of predetermined parts. The position correction information includes relative moving direction and moving amount for correcting the relative position of the X-ray irradiation unit (1) with respect to the imaging object of the subject (201) to a position for enabling imaging of an X-ray image in which the position relations between the outer edges of the plurality of predetermined parts are shown with predetermined position relations.SELECTED DRAWING: Figure 2

Description

The present invention relates to an X-ray imaging apparatus and an imaging position correction method.

2. Description of the Related Art Conventionally, an X-ray imaging apparatus is known (see Patent Literature 1, for example).

The above-mentioned Patent Document 1 discloses an X-ray device that includes an X-ray source that emits X-rays, an X-ray detector that detects X-rays, and a display device that displays a composite moving image obtained by synthesizing an optical moving image and a guide image. An imaging device is disclosed. In this X-ray imaging apparatus, the operator instructs the patient to change the imaging position while viewing the composite moving image displayed on the display device in the control room. In addition, the patient changes his or her imaging position while viewing the composite moving image displayed on the display device in the imaging room.

JP 2014-117368 A

Here, even experienced radiological technologists have a high degree of difficulty in taking X-ray images in the field of orthopedic surgery. For example, when taking an X-ray image of the lateral side of the knee joint for diagnosis of diseases around the knee joint such as osteochondritis dissecans and osteoarthritis of the knee, in order to accurately diagnose the disease, Adjust the imaging position so that the outer edge of the medial condyle of the femur (the portion on the midline side of the knee of the femur) and the outer edge of the lateral condyle (the portion on the side opposite to the midline side of the knee of the femur) are aligned. It is necessary to take superimposed X-ray images. However, since there are individual differences in the shape of the bones and how the flesh of the leg is attached, the imaging position is adjusted from the appearance of the subject, and the X-axis is adjusted so that the outer edge of the medial condyle and the outer edge of the lateral condyle of the femur overlap. Acquiring line images is very difficult even for experienced radiologists. Therefore, in order to obtain an X-ray image that enables accurate diagnosis such that the outer edge of the medial condyle and the outer edge of the lateral condyle of the femur overlap each other, it is necessary to obtain an X-ray image. It is necessary to correct the imaging position based on the line image. In order to capture an X-ray image that enables accurate diagnosis, it is necessary to repeat the capturing of the X-ray image and the correction of the capturing position. Therefore, the exposure dose of the subject and the imaging time are increased. Therefore, it is desired to acquire an X-ray image that enables accurate diagnosis while suppressing an increase in exposure dose and imaging time.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and one object of the present invention is to enable accurate diagnosis while suppressing increases in exposure dose and imaging time. An object of the present invention is to provide an X-ray imaging apparatus capable of acquiring a line image and a method of correcting an imaging position.

An X-ray imaging apparatus according to a first aspect of the present invention comprises an X-ray irradiator that irradiates an object to be examined with X-rays, and an X-ray that is emitted from the X-ray irradiator and passes through the object and detects the X-rays. a detection unit, and specifying the outer edge of each of the plurality of predetermined portions in one imaging object of the subject in the X-ray image captured based on the detection signal of the X-ray detection unit, and the identified plurality of predetermined portions a correction information acquisition unit for acquiring position correction information for correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the positional relationship between the outer edges of the A relative position for correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject to a position where an X-ray image can be captured with a predetermined positional relationship between the outer edges of a plurality of predetermined portions. including the direction of movement and the amount of movement.

A method for correcting an imaging position according to a second aspect of the present invention includes an irradiation step of irradiating an object to be examined with X-rays from an X-ray irradiation unit, a detection step of detecting the X-rays transmitted through the object, and Identifying the outer edges of each of a plurality of predetermined portions in one imaging object of a subject in an X-ray image captured based on X-ray detection, and determining the positional relationship between the outer edges of the identified plurality of predetermined portions. a correction information acquisition step for acquiring position correction information for correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject, wherein the position correction information is the imaging object of the subject Relative movement direction and movement amount for correcting the relative position of the X-ray irradiation unit to a position where the positional relationship between the outer edges of a plurality of predetermined parts can be captured in a predetermined positional relationship so that an X-ray image can be captured including.

In the X-ray imaging apparatus according to the first aspect of the present invention and the imaging position correcting method according to the second aspect of the present invention, the outer edge of each of a plurality of predetermined portions of one imaging object of a subject in an X-ray image is specified. Position correction information for correcting the relative position of the X-ray irradiation unit with respect to the object to be imaged of the subject is acquired based on the positional relationship between the outer edges of the specified plurality of predetermined portions. The position correction information indicates the relative position of the X-ray irradiation unit with respect to the imaging object of the subject, and the position where the X-ray image can be captured in which the positional relationship between the outer edges of a plurality of predetermined portions is a predetermined positional relationship. It contains the relative movement direction and movement amount for correcting to As a result, it is possible to capture an X-ray image in which the relative position of the X-ray irradiation unit with respect to the object to be imaged, such as a bone or an artificial joint, is captured in a predetermined positional relationship between the outer edges of a plurality of predetermined portions. Since the position correction information including the relative movement direction and movement amount for correcting the correct position is acquired, the acquired position correction information is used to notify the relative movement direction and movement amount necessary for correction. Accordingly, a user such as a radiological technologist can accurately correct the imaging position based on the notification result. As a result, it is possible to reduce the number of times the X-ray image capturing and the capturing position correction are repeated. As a result, it is possible to provide an X-ray imaging apparatus and an imaging position correction method capable of obtaining X-ray images that enable accurate diagnosis while suppressing increases in exposure dose and imaging time. In addition, by performing control to change the relative position of the X-ray irradiator using the acquired position correction information, the relative position of the X-ray irradiator with respect to the object to be imaged of the subject, such as a bone or an artificial joint. The position can be accurately corrected to a position at which an X-ray image captured with a predetermined positional relationship suitable for diagnosis between outer edges of a plurality of predetermined portions can be captured. As a result, it is possible to reduce the number of times the X-ray image capturing and the capturing position correction are repeated. As a result, it is possible to provide an X-ray imaging apparatus and an imaging position correction method capable of obtaining X-ray images that enable accurate diagnosis while suppressing increases in exposure dose and imaging time.

1 is a schematic diagram showing the overall configuration of an X-ray imaging apparatus according to a first embodiment of the present invention; FIG. 1 is a block diagram showing the configuration of an X-ray imaging apparatus according to a first embodiment of the present invention; FIG. FIG. 4 is a diagram showing an example of a sleeping posture of a subject when imaging a knee joint side surface; FIG. 4 is a diagram showing the bone structure around the joint of the right knee viewed from behind. It is an example of a main shot image of the side of the knee joint. It is an example of the pre-shot image which image|photographed the knee-joint side surface. FIG. 11 is a diagram showing an example of calculation of a deviation amount using a learned model by a processing unit; 4 is a graph of function f(x) of X-ray tube position x; FIG. 4 is a diagram showing bones around a knee joint; It is the figure which showed an example of the display by the display part of an operating terminal. FIG. 1 is a first diagram for explaining correction of an imaging position by the X-ray imaging apparatus according to the first embodiment of the present invention; FIG. 2 is a second diagram for explaining correction of an imaging position by the X-ray imaging apparatus according to the first embodiment of the present invention; FIG. 10 is a diagram showing an example of a method of acquiring position correction information during humerus imaging; FIG. 4 is a diagram showing X-ray images around the elbow joint before and after position correction; FIG. 7 is a diagram showing a processing flow of correcting an imaging position in an automatic correction mode of the X-ray imaging apparatus according to the first embodiment; FIG. 7 is a diagram showing a processing flow of correcting an imaging position in a manual correction mode of the X-ray imaging apparatus according to the first embodiment; It is a figure for demonstrating the imaging|photography direction of a scapula. FIG. 4 is a diagram showing another example of an X-ray imaging apparatus according to the present invention; FIG. 19 is a diagram showing an example of display by the display unit of the operation terminal of the X-ray imaging apparatus shown in FIG. 18; FIG. 11 is a block diagram showing the configuration of an X-ray imaging apparatus according to a second embodiment; FIG. FIG. 10 is a diagram for explaining acquisition of parameter information from a pre-shot image; FIG. FIG. 10 is a diagram showing a processing flow of an imaging position correction method for an X-ray imaging apparatus according to the second embodiment; FIG. 11 is a block diagram showing the configuration of an X-ray imaging apparatus according to a third embodiment; It is a figure for demonstrating acquisition of the parameter information from an appearance image. FIG. 11 is a block diagram showing the configuration of an X-ray imaging apparatus according to a fourth embodiment; FIG. 4 is a diagram for explaining acquisition of parameter information from an X-ray image different from a pre-shot image;

Embodiments embodying the present invention will be described below with reference to the drawings.

[First embodiment]
The configuration of an X-ray imaging apparatus 100 according to the first embodiment will be described with reference to FIGS. 1 to 14. FIG.

As shown in FIG. 1 , the X-ray imaging apparatus 100 includes an X-ray irradiation section 1 and a detection section 2 . The X-ray imaging apparatus 100 also includes a table 3 on which the subject 201 is placed, an irradiation unit moving mechanism 4, a table moving mechanism 5, a detecting unit moving mechanism 6, and an apparatus control unit 7. . The X-ray imaging apparatus 100 is configured to perform imaging using X-rays emitted from an X-ray irradiation unit 1 suspended from the ceiling. Note that the irradiation unit moving mechanism 4 and the tabletop moving mechanism 5 are examples of the "moving mechanism" in the scope of claims. Also, the device control unit 7 is an example of a "movement control unit" in the scope of claims.

The X-ray irradiation unit 1 is configured to irradiate an object 201 with X-rays. The X-ray irradiation unit 1 also includes an X-ray source (X-ray tube) that irradiates the subject 201 with X-rays, and a collimator that adjusts the X-ray irradiation range. The X-ray irradiation unit 1 also includes a gripping unit 1a provided for the user 202 to grip when the user 202 manually moves the X-ray irradiation unit 1 . The X-ray irradiation unit 1 also has a display unit 1b, and the display unit 1b displays the amount of power assist when the user 202 moves the X-ray irradiation unit 1 by gripping the grip unit 1a, imaging conditions, and the like. configured as possible. The display unit 1b is also configured to display position correction information, which will be described later. The display unit 1b is composed of, for example, a liquid crystal display or an organic EL display.

The detection unit 2 is configured to detect X-rays emitted from the X-ray irradiation unit 1 and transmitted through the subject 201 . As shown in FIG. 1, the detection unit 2 includes an X-ray detection unit 21 used for imaging a subject 201 lying on the tabletop 3 (recumbent position or lateral position), and an X-ray detection unit 22 used for imaging in an upright posture (standing position). The X-ray detection units 21 and 22 are, for example, FPDs (Flat Panel Detectors) and detect X-rays that have passed through the subject 201 .

The irradiation unit moving mechanism 4 is configured to change the position of the X-ray irradiation unit 1 relative to the subject 201 by moving the X-ray irradiation unit 1 . In the X-ray imaging apparatus 100, the X-ray irradiation unit 1 is supported by the irradiation unit moving mechanism 4 so as to be suspended from the ceiling. The X-ray irradiator 1 is movably supported in the imaging room by an irradiator moving mechanism 4 . The irradiation unit moving mechanism 4 includes motors and electromagnetic brakes (not shown) corresponding to each of the X, Y and Z directions. The X-ray irradiation unit 1 is configured to be movable in each of the X direction, the Y direction, and the Z direction by the irradiation unit moving mechanism 4 . The irradiation unit moving mechanism 4 also includes encoders (not shown) used to control the movement of the X-ray irradiation unit 1 corresponding to each of the X direction, Y direction, and Z direction. In addition, the irradiation unit moving mechanism 4 includes potentiometers (not shown) corresponding to the X, Y, and Z directions, and controls the X-ray irradiation in each of the X, Y, and Z directions. The position of the unit 1 is configured to be detectable.

Further, the X-ray irradiation unit 1 is configured to be rotatable around the Z-axis. The X-ray irradiator 1 is configured to rotate around each of the axes perpendicular to the Z-axis, such as the X-axis and the Y-axis. In the state shown in FIG. 1, the X-ray irradiation unit 1 is rotatable around the Y axis. The X-ray irradiation unit 1 is configured to be able to change the X-ray irradiation direction and angle by rotating around an axis perpendicular to the Z-axis. The irradiation unit moving mechanism 4 also includes motors and electromagnetic brakes (not shown) corresponding to each of the two rotatable axes of the X-ray irradiation unit 1 . The irradiation unit moving mechanism 4 also includes an encoder (not shown) and a potentiometer (not shown) corresponding to each of the two rotatable axes of the X-ray irradiation unit 1 . In addition, the irradiation unit moving mechanism 4 electrically outputs the length of the wire pulled out by the movement of the X-ray irradiation unit 1, thereby determining the absolute position of the X-ray irradiation unit 1 in the vertical direction (Z direction). can be detected.

The table moving mechanism 5 moves the table 3 to change the position of the subject 201 with respect to the X-ray irradiation section 1, thereby changing the relative position of the X-ray irradiation section 1 with respect to the subject 201. It is configured. The table moving mechanism 5 includes motors and electromagnetic brakes (not shown) corresponding to the X, Y and Z directions. The top plate 3 is configured to be movable in each of the X, Y and Z directions by a top plate moving mechanism 5 .

The detector moving mechanism 6 includes a lying position moving mechanism 61 and a standing position moving mechanism 62 . The lying position moving mechanism 61 and the standing position moving mechanism 62 respectively hold the X-ray detection units 21 and 22 so as to be movable according to the imaging region of the subject 201 . The supine position moving mechanism 61 is a mechanism for moving the X-ray detection unit 21 and is configured to be able to change the position of the X-ray detection unit 21 with respect to the subject 201 . The standing position moving mechanism 62 is a mechanism for moving the X-ray detection unit 22 and is configured to be able to change the position of the X-ray detection unit 22 with respect to the subject 201 .

The device control unit 7 is configured to control the entire X-ray imaging device 100 . Specifically, the device control unit 7 controls X-ray irradiation by the X-ray irradiation unit 1 such as starting and stopping X-ray irradiation, controls changes in the X-ray irradiation range by the X-ray irradiation unit 1, and controls the detection unit 2 (X-ray detection units 21 and 22), movement control of the X-ray irradiation unit 1 by the irradiation unit moving mechanism 4, and movement control of the tabletop 3 by the tabletop moving mechanism 5. is configured to Further, the apparatus control section 7 is configured to control the movement of the X-ray detection section 21 by the lying position movement mechanism 61 and to control the movement of the X-ray detection section 22 by the standing position movement mechanism 62 .

The device control unit 7 includes a processor such as a CPU (Central Processing Unit) or FPGA (field-programmable gate array). Further, the device control section 7 is configured to be able to receive detection signals from the encoder and potentiometer provided in the irradiation section moving mechanism 4 . Further, the device control section 7 is configured to control the motor and the electromagnetic brake provided in the irradiation section moving mechanism 4 .

The X-ray imaging apparatus 100 also includes a processing device 8 including a processing unit 81 and a storage unit 82, as shown in FIG. The processing device 8 is, for example, a PC (Personal Computer) operated by a user 202 such as a radiologist. Input devices (not shown) such as a keyboard and a mouse, and display devices (not shown) such as a liquid crystal display or an organic EL display are connected to the processing device 8 . The processing device 8 is communicably connected to the device control section 7 . Further, the processing device 8 may be configured integrally with the device control section 7 .

Processing unit 81 identifies the outer edge of each of a plurality of predetermined portions of one bone of subject 201 in an X-ray image captured based on detection signals from detection unit 2 (X-ray detection units 21 and 22). position correction information for correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 based on the positional relationship between the outer edges of the plurality of specified predetermined portions. there is The processing unit 81 includes a CPU, a GPU (Graphics Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. Note that the processing unit 81 is an example of a "correction information acquiring unit" in the scope of claims. Also, a bone is an example of the "imaging object" in the scope of claims.

The position correction information indicates the relative position of the X-ray irradiator 1 with respect to the bones of the subject 201, and is a position where an X-ray image can be captured with a predetermined positional relationship between the outer edges of a plurality of predetermined portions. It contains the relative movement direction and movement amount for correcting to

The storage unit 82 includes a non-volatile storage medium such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive). The storage unit 82 stores learned models (learned models 82a, 82b, 82c, 82d, and 82e) machine-learned using X-ray images of bones as input data. The trained models 82a, 82b, 82c, 82d and 82e are models using U-Net, for example. Machine learning using X-ray images as input data may be any of supervised learning, unsupervised learning, and reinforcement learning. In the first embodiment, the learned model stored in the storage unit 82 exists for each of a plurality of predetermined portions of the imaging region. The learned model stored in the storage unit 82 has learned feature points in each of a plurality of predetermined parts of the imaging region. The learned models 82 a and 82 b are learned models used when imaging the knee joint of the subject 201 . The learned models 82 c , 82 d and 82 e are learned models used when imaging the elbow joint of the subject 201 . Note that the learned models (learned models 82a, 82b, 82c, 82d, and 82e) may be stored in a server connected to the X-ray imaging apparatus 100 via a network. Further, the storage unit 82 may store a learned model created for each imaging part.

Further, in the first embodiment, when the knee joint of the subject 201 is imaged, the processing unit 81 inputs the X-ray image to the learned models 82a and 82b, so that the input X-ray image and to calculate the position correction information based on the acquired outer edges of the plurality of predetermined portions. In addition, in the first embodiment, when imaging the elbow joint of the subject 201, the processing unit 81 inputs X-ray images to the learned models 82c, 82d, and 82e to obtain the input X-ray image. It is configured to acquire outer edges of a plurality of predetermined portions based on the line image, and to calculate position correction information based on the acquired outer edges of the plurality of predetermined portions.

The X-ray imaging apparatus 100 also includes an operation terminal 9 . The operation terminal 9 is a terminal for the user 202 to operate the X-ray imaging apparatus 100 . The operation terminal 9 is communicably connected to the device control section 7 and the processing device 8 . The user 202 can use the operation terminal 9 to change the position of the X-ray irradiation unit 1 and perform operations for X-ray imaging. The operation terminal 9 includes a display section 91 and an operation section 92 . The display unit 91 is configured by, for example, a liquid crystal display or an organic EL display. Also, the operation unit 92 is a user interface for operating the X-ray imaging apparatus 100 . Operation unit 92 includes, for example, a switch or a remote controller. Also, the operation unit 92 may include a touch panel provided on the display unit 91 .

The X-ray imaging apparatus 100 is configured to notify the position correction information acquired by the processing unit 81 . In the first embodiment, the X-ray imaging apparatus 100 is configured to notify the position correction information by displaying on the display unit 91 of the operation terminal 9 . Further, in the first embodiment, the X-ray imaging apparatus 100 can notify the position correction information by displaying the display unit 1b of the X-ray irradiation unit 1. FIG. Details of display by the display unit 91 will be described later.

(Correction when photographing the knee joint)
As shown in FIG. 3 , when imaging the knee, the subject 201 is placed on the top plate 3 and cushions 203 and 204 are used to adjust the position of the knee, which is the part to be observed, and the position of the thigh. In addition, the sleeping posture of the subject 201 is adjusted so that the degree of rotation of the lower leg, the degree of raising the lower leg (bending angle of the knee), and the like are appropriate. Then, an X-ray image of the observation target region of the subject 201 is captured in the adjusted sleeping posture.

Then, the X-ray imaging apparatus 100 identifies (estimates) a plurality of predetermined portions of the femur 31 from the X-ray image as shown in FIG. It is configured to acquire position correction information for correcting the position.

In addition, the X-ray imaging apparatus 100, from the time of imaging the main shot image 23 (see FIG. 5), which is an X-ray image captured after correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201, A pre-shot image 24 (see FIG. 6), which is an X-ray image generated based on irradiation of X-rays with a small radiation dose, can be captured. For example, the radiation dose when the pre-shot image 24 is captured is about 1/50 to 1/100 of that when the main shot image 23 is captured. In the first embodiment, the main shot image 23 is an image used for disease diagnosis. Note that the main shot image 23 is an example of the "post-position correction image" in the claims, and the pre-shot image 24 is an example of the "pre-position correction image" in the claims.

In the first embodiment, the processing unit 81 of the X-ray imaging apparatus 100 acquires position correction information based on the positional relationship between the outer edges of a plurality of predetermined portions of the bones of the subject 201 in the preshot image 24. is configured to

In the X-ray imaging apparatus 100 of the first embodiment, as shown in FIG. 5, the outer edge of the medial condyle 31a (see FIG. 6) and the outer edge of the lateral condyle 31b (see FIG. 6) of the femur 31 overlap each other. In order to capture such an X-ray image, the processing unit 81 acquires position correction information and corrects the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 . The medial condyle 31a and the lateral condyle 31b are an example of "a plurality of predetermined portions" in the claims.

The processing unit 81 determines the relative positions of the outer edges of the plurality of predetermined portions in the X-ray image based on the positional relationship between the outer edges of the plurality of predetermined portions in one bone of the subject 201 in the X-ray image. I am getting the deviation. Then, the processing unit 81 is configured to acquire position correction information based on the acquired relative positional deviation between the outer edges of the plurality of predetermined portions. In the first embodiment, when imaging the side of the knee joint, the processing unit 81 of the X-ray imaging apparatus 100 controls the outer edge of the medial condyle 31a of the femur 31 (portion of the femur 31 on the knee-side midline side), and It is configured to acquire position correction information based on the positional deviation between the outer edges of the lateral condyle 31b (the portion on the side opposite to the midline side of the knee of the femur 31).

In addition, the processing unit 81 acquires the relative positional deviation between the outer edges of the plurality of predetermined portions based on how the outer edges of the plurality of predetermined portions of the bone of the subject 201 overlap in the X-ray image. It is configured. In the first embodiment, as shown in FIG. 7, the processing unit 81 uses learned models 82a and 82b to compare outer edges of a plurality of predetermined portions on the knee side of the femur 31 of the subject 201. Getting the misalignment. Specifically, the processing unit 81 identifies (estimates) the outer edge of the medial condyle 31a from the pre-shot image 24 by segmentation processing using the learned model 82a. In addition, the processing unit 81 identifies (estimates) the outer edge of the lateral condyle 31b from the pre-shot image 24 by segmentation processing using the learned model 82b. Then, based on the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b specified (estimated) from the pre-shot image 24, the processing unit 81 determines the distance between the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b of the femur 31. deviation (amount of deviation and direction of deviation) is calculated. In the analysis of the displacement amount and displacement direction by the processing unit 81, one of the medial condyle 31a and the lateral condyle 31b is virtually moved so that the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b are aligned. By searching for the position where the area caused by the displacement between the medial condyle 31a and the lateral condyle 31b after movement is minimized, the displacement amount and displacement direction are identified. Further, in the analysis of the amount of displacement and the direction of displacement by the processing unit 81, the portion where the maximum width of displacement exists may be specified in the image obtained by extracting the outer edge of each of the medial condyle 31a and the lateral condyle 31b.

Then, based on the calculated deviation between the outer edge of the medial condyle 31 a and the outer edge of the lateral condyle 31 b of the femur 31 , the processing unit 81 performs a plurality of motions when imaging the knee side of the femur 31 of the subject 201 . Position correction information for correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 is calculated so that an X-ray image in which the outer edges of the predetermined portions of the X-ray irradiation unit 1 overlap each other can be captured. It is Specifically, the processing unit 81 determines the movement direction and movement of the X-ray irradiation unit 1 based on the calculated deviation (movement vector) between the outer edge of the medial condyle 31 a and the outer edge of the lateral condyle 31 b of the femur 31 . The amount (movement distance) is calculated as the position correction information. As for the position correction information, as shown in FIG. 8, the displacement amount f between the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b of the femur 31 is It is calculated using the fact that In the first embodiment, the estimated position is estimated as a position where an X-ray image in which the outer edges of a plurality of predetermined portions (the medial condyle 31a and the lateral condyle 31b) overlap each other can be captured (the position where the displacement amount f is 0). x' is a function of the deviation amount _f1 between the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b calculated from the pre-shot image ₂₄ taken at the X-ray tube position x1 and the X-ray tube position x. It is calculated based on the slope α of f(x). The inclination α varies depending on various parameters including apparatus parameters such as SID (Source to image receptor distance) and parameters set corresponding to the subject 201 (patient) at the time of imaging.

Also, pre-processing may be performed on the pre-shot image 24 prior to identifying the outer edge of each of the medial condyle 31a and the lateral condyle 31b. For example, a high-pass filter may be used as preprocessing to remove unnecessary signals such as noise. In addition, as preprocessing, a process of horizontally reversing the radiographed X-ray image of the knee (reversing the left knee to the right knee or reversing the right knee to the left) may be performed. In this case, even if the storage unit 82 stores only the learned models corresponding to one of the right knee and the left knee, the processing unit 81 stores the outer edges of the medial condyles 31a of both the right knee and the left knee. It is possible to calculate the amount of deviation from the outer edge of the lateral condyle 31b and acquire position correction information.

In addition, the processing unit 81 specifies the outer edges of each of the medial condyle 31a and the lateral condyle 31b, and calculates the degree of overlap (positional relationship) between the medial condyle 31a and the lateral condyle 31b. In addition, calculation may be performed based on bones of the subject 201 other than the femur 31, such as the tibia 32, fibula 33, patella 34, and sesamoid bone 35 shown in FIG.

For example, when the knee is slightly externally rotated (external hip), the fibula 33 moves further posteriorly (away from the patella 34) and the proximal tibiofibular joint becomes clearer. The sesamoid bone 35 is separated from the condyles of the femur 31 (the medial condyle 31a and the lateral condyle 31b). Also, when the knee is slightly internally rotated (inward thigh), the fibula 33 moves further forward (in a direction approaching the patella 34) and overlaps with the tibia 32 more. The sesamoid bone 35 then approaches the condyles of the femur 31 (the medial condyle 31a and the lateral condyle 31b). Therefore, based on the position of the fibula 33 or the position of the sesamoid bone 35, it is possible to determine whether the knee is slightly externally rotated (externally rotated) or internally rotated (innerly). .

Further, in the vertical direction in which the femur 31 extends, when there is a positional deviation between the medial condyle 31a of the femur 31 and the lateral condyle 31b of the femur 31, the medial plateau 32a of the tibia 32, A positional deviation occurs between the tibia 32 and the lateral plateau 32b. Therefore, based on the positional relationship between the medial plateau 32a of the tibia 32 and the lateral plateau 32b of the tibia 32, there is a vertical displacement between the medial condyle 31a of the femur 31 and the lateral condyle 31b of the femur 31. It is possible to determine whether

In addition, the display unit 91 of the operation terminal 9 notifies the position correction information of the subject for correcting the X-ray image in which the outer edges of a plurality of predetermined portions appear in a predetermined positional relationship to a position where the image can be captured. The direction and amount of movement of the X-ray irradiation unit 1 relative to the bone 201 are displayed. For example, as shown in FIG. 10 , the display unit 91 of the operation terminal 9 displays a chart showing the amount and direction of movement of the X-ray irradiation unit 1 relative to the bones of the subject 201 . Thereby, the user 202 can understand from the display of the display unit 91 in what direction and how much the position of the X-ray irradiation unit 1 should be corrected with respect to the bone of the subject 201 . The display on the display unit 91 may be a display using only characters such as "direction of movement: 10 o'clock direction, amount of movement: 3 cm", or a combination of images, drawings, characters, and the like. There may be.

Moreover, the display unit 1b (see FIG. 1) of the X-ray irradiation unit 1 is configured so that the display is interlocked with the display unit 91. As shown in FIG. As a result, the user 202, while gripping the grip portion 1a (see FIG. 1) of the X-ray irradiation unit 1, can obtain the relative position of the X-ray irradiation unit 1 with respect to the bone of the subject 201 necessary for correcting the imaging position. The movement direction and movement amount can be confirmed by the display section 1b.

(Control of movement of X-ray irradiation unit)
The X-ray imaging apparatus 100 is configured to perform control for changing the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 based on the position correction information. In the first embodiment, the X-ray imaging apparatus 100 has an automatic correction mode in which the imaging position is automatically corrected under the control of the apparatus control unit 7, and a manual correction mode in which the imaging position is corrected manually by the user 202. mode is provided as a mode for correcting the photographing position. The X-ray imaging apparatus 100 is configured so that the mode for correcting the imaging position can be switched between an automatic correction mode and a manual correction mode based on a switching operation by the user 202 .

In the first embodiment, in the automatic correction mode of the X-ray imaging apparatus 100, the apparatus control unit 7 moves the position of the X-ray irradiation unit 1 based on the position correction information to irradiate the bone of the subject 201 with X-rays. It is configured to perform automatic correction for automatically changing the relative position of the unit 1 . In addition, the X-ray imaging apparatus 100 restricts movement of the X-ray irradiation unit 1 during manual correction (manual correction mode) in which correction is performed by moving the X-ray irradiation unit 1 based on the operation of the user 202. It is configured.

Specifically, in the automatic correction mode, the apparatus control unit 7 adjusts the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 based on the position correction information acquired by the processing unit 81. Control is performed to automatically move the X-ray irradiating unit 1 so that the positional relationship between the outer edges of the predetermined portion is at a position where the X-ray image captured with the predetermined positional relationship can be captured. That is, under the control of the device control unit 7 based on the position correction information, the irradiation unit moving mechanism 4 moves the X-ray irradiation unit 1 to generate an X-ray image in which the outer edges of a plurality of predetermined portions are captured in a predetermined positional relationship. Move to a position where shooting is possible.

Further, in the X-ray imaging apparatus 100, as shown in FIGS. 11 and 12, by changing the position in the horizontal direction (XY direction) according to the fan-beam characteristics of the X-rays emitted from the X-ray irradiation unit 1, Correction can be performed without changing the X-ray irradiation angle of the X-ray irradiation unit 1 . For example, by moving the X-ray irradiation point (X-ray irradiation unit 1) from the position shown in the left diagram of FIG. 11 to the position shown in the left diagram of FIG. X-rays can be applied through the outer edge of the lateral condyle 31b of 31. As a result, the outer edge of the medial condyle 31a of the femur 31 and the outer edge of the lateral condyle 31b of the femur 31 overlap with each other even if the X-ray irradiation angle of the X-ray irradiation unit 1 is not changed (right side in FIG. 12). (see figure) can be taken. When correcting the imaging position, in addition to the position in the horizontal direction (XY direction), the X-ray irradiation angle of the X-ray irradiation unit 1 and the position of the X-ray irradiation unit 1 in the vertical direction (Z direction) are changed. You may Further, when correcting the imaging position, in addition to moving the X-ray irradiation unit 1 by the irradiation unit moving mechanism 4, the table moving mechanism 5 moves the table 3 on which the subject 201 is placed. may

Further, when the X-ray irradiation unit 1 is moved based on the operation of the user 202, the device control unit 7 controls the movement of the X-ray irradiation unit 1 based on the position correction information acquired by the processing unit 81. I do. Specifically, in the manual correction mode, the device control unit 7 restricts the movement of the X-ray irradiation unit 1 by controlling the locking of the irradiation unit moving mechanism 4 by the electromagnetic brake based on the position correction information. is configured to

As described above, in the first embodiment, the apparatus control unit 7 controls the relative movement of the X-ray irradiation unit 1 with respect to the bone of the subject 201 by the irradiation unit moving mechanism 4 based on the position correction information acquired by the processing unit 81 . position change control.

(Correction when photographing the elbow joint)
In addition, in the first embodiment, the processing unit 81 also performs imaging of the elbow side (elbow joint) of the humerus 36 of the subject 201. Based on the positional relationship between the outer edges, it is configured to acquire the relative positional deviation between the outer edges of the plurality of predetermined portions. In the first embodiment, the processing unit 81 uses the learned models 82c, 82d, and 82e to acquire the relative positional displacement between the outer edges of a plurality of predetermined portions on the elbow side of the humerus 36 of the subject 201. ing. When imaging the elbow joint (the elbow side of the humerus 36) of the subject 201, either of the X-ray detectors 21 and 22 (see FIG. 1) may be used.

In the first embodiment, when imaging the elbow side (elbow joint) of the humerus 36 of the subject 201, the processing unit 81 is positioned at a position where an X-ray image in which the outer edges of a plurality of predetermined portions appear concentrically can be captured. Furthermore, it is configured to calculate position correction information for correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 . Specifically, the processing unit 81 identifies (estimates) each of the portions A, B and C of the humerus 36 using the learned models 82c, 82d and 82e. Then, the processing unit 81 acquires the relative displacement between the specified portions A, B, and C of the humerus 36 . Further, the processing unit 81 performs an X-axis image on which the outer edges of a plurality of predetermined portions (portions A, B, and C) are concentrically captured based on the obtained relative positional deviations of the portions A, B, and C of the humerus 36 . Position correction information is calculated for correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 to a position where a line image can be captured. In the first embodiment, the processing unit 81 sets the X-ray tube position x (X-ray irradiation point) to a plurality of predetermined portions (parts The moving direction and moving amount (moving distance) of the X-ray irradiation unit 1 for correcting the X-ray image in which the outer edges of A, B and C) appear concentrically are calculated as the position correction information. . As for the calculation method of the position correction information, the same calculation method as the above-described calculation method for photographing the knee joint is used.

Specifically, as shown in the upper diagram of FIG. The outer edges of the elbow-side portions A and C are overlapped, and the outer edges of a plurality of elbow-side predetermined portions (portions A, B, and C) of the humerus 36 are concentrically projected (see the lower diagram of FIG. 13). Position correction information for correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 is calculated. The portion A is the convex portion of the humeral head 36a. Also, portion B is a concave portion of the trochlea 36b of the humerus 36, and portion C is a convex portion of the trochlea 36b of the humerus 36. As shown in FIG. Parts A, B, and C are examples of "a plurality of predetermined parts" in the scope of claims. It should be noted that the calculation of the position correction information at the time of photographing the elbow joint is based on at least one of the positional relationships between the outer edges of the radius 37 and the ulna 38 and a plurality of predetermined portions (portions A and B) of the humerus 36 on the elbow side. and the positional relationship of C). FIG. 13 shows a view from the position where the portion C (the convex portion of the pulley 36b) of the humerus 36 is shifted upward (see the center view of FIG. 13), the portion A (the convex portion of the capitellum 36a) and the portion C (the convex portion of the humeral head 36a). A position where the outer edges of the pulley 36b (the convex portion of the pulley 36b) overlap concentrically, and the outer edge of the portion B (the concave portion of the pulley 36b) is concentrically reflected inside the outer edges of the portions A and C (see the lower diagram of FIG. 13) ) shows an example of correction. The relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 is determined based on the position correction information by raising the upper arm, by raising a table (not shown) on which the upper arm is placed, or by adjusting the position of the X-ray irradiation unit By changing the position of 1, the portion C (trochlear 36b) of the humerus 36 is corrected from the position (see the center view of FIG. 13) at which it is shifted upward.

Also, the shooting of the pre-shot image 24 and the correction of the shooting position may be performed multiple times. For example, as shown in FIG. 14, based on the pre-shot image 24a of the elbow joint of the subject 201, after correcting the imaging position, the pre-shot image 24b may be imaged again. Then, based on the second pre-shot image 24 (pre-shot image 24b), the photographing position may be corrected again, and the main shot image 23 may be photographed. In the example shown in FIG. 14 , an X-ray image (this A shot image 23) is taken.

(Position correction processing)
Next, a processing flow of position correction using the automatic correction mode of the X-ray imaging apparatus 100 according to the first embodiment will be described with reference to FIG.

First, in step 301 , the subject 201 is irradiated with X-rays from the X-ray irradiation unit 1 . In step 301, as described above, X-ray irradiation is performed with a radiation dose smaller than that used when the main shot image 23 is captured. Note that step 301 is an example of the "irradiation step" in the scope of claims. Then, after step 301 is completed, the processing steps transition to step 302 .

In step 302, X-rays that have passed through subject 201 are detected. In step 302, X-rays transmitted through the subject 201 are detected by the detector 2 (X-ray detector 21 or 22), as described above. Accordingly, in step 302, a pre-shot image 24 is captured. Note that step 302 is an example of a "detection step" in the claims. Then, after step 302 is completed, the processing steps transition to step 303 .

At step 303, position correction information is obtained. In step 303, as described above, the outer edge of each of the plurality of predetermined portions of the bone of the subject 201 in the X-ray image (pre-shot image 24) captured based on X-ray detection is specified, Position correction information for correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 is acquired based on the positional relationship between the outer edges of the specified plurality of predetermined portions. Note that step 303 is an example of a "correction information acquisition step" in the scope of claims. Then, after step 303 is completed, the processing steps transition to step 304 . Note that the transition to step 304 may be performed automatically, or may be performed based on an operation by the user 202 such as an operation on the operation unit 92 of the operation terminal 9 . Further, after step 303 is completed, the position correction information may be displayed on the display section 91 or the display section 1b.

Then, in step 304, automatic position correction is performed. In step 304, control is performed to change the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 based on the position correction information. Specifically, as described above, the device control unit 7 controls the irradiation unit moving mechanism 4 to move the X-ray irradiation unit 1 based on the position correction information. Thereby, the relative position of the X-ray irradiation unit 1 with respect to the subject 201 (bone of the subject 201) is corrected. Then, the position correction processing using the X-ray imaging apparatus 100 is completed. Note that step 304 is an example of a "position correction step" in the scope of claims.

After step 304 is completed, the user 202 performs an X-ray image capturing operation, whereby an X-ray image is captured with the image capturing position corrected. Alternatively, after step 304 is completed, X-ray imaging may be automatically performed.

Next, a processing flow of position correction using the manual correction mode of the X-ray imaging apparatus 100 according to the first embodiment will be described with reference to FIG.

First, in steps 401, 402 and 403, processing similar to steps 301, 302 and 303 in the automatic correction mode is performed. Then, after step 403 is completed, the processing steps transition to step 404 . Note that step 401 is an example of the "irradiation step" in the claims, and step 402 is an example of the "detection step" in the claims. Also, step 403 is an example of a "correction information acquisition step" in the scope of claims.

In step 404, display of position correction information is performed. At step 404, as described above, the position correction information acquired at step 403 is displayed by the display unit 91 and the display unit 1b. After the position correction information is displayed by the display section 91 and the display section 1b (after step 404 is completed), the process proceeds to step 405. FIG. Note that step 404 is an example of a "position correction step" in the scope of claims.

At step 405, manual position correction is performed. In step 405, the user 202 moves the X-ray irradiation unit 1 while confirming the display on the display unit 91 or the display unit 1b, thereby correcting the imaging position. In the correction of the imaging position in step 405 , the X-ray irradiation unit 1 may be moved by the hand of the user 202 who grips the grip portion 1 a of the X-ray irradiation unit 1 , or the operation unit 92 of the operation terminal 9 may be moved by the user 202 . It may be moved by the irradiation unit moving mechanism 4 based on the operation of 202 .

Then, after step 405 is completed, the user 202 performs an X-ray image capturing operation so that an X-ray image is captured with the image capturing position corrected.

(Effect of the first embodiment)
The following effects can be obtained in the first embodiment.

In the first embodiment, based on the positional relationship between the outer edges of a plurality of predetermined portions of the bone of the subject 201 in the X-ray image, the relative position of the X-ray irradiation unit 1 with respect to the bone of the subject 201 (imaging object) Position correction information for correcting the position is acquired. The position correction information indicates the relative position of the X-ray irradiator 1 with respect to the bones of the subject 201, and is a position where an X-ray image can be captured with a predetermined positional relationship between the outer edges of a plurality of predetermined portions. It contains the relative movement direction and movement amount for correcting to As a result, the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 is corrected to a position where an X-ray image in which the outer edges of a plurality of predetermined portions are captured in a predetermined positional relationship can be captured. Since the position correction information including the relative movement direction and movement amount of is acquired, by using the acquired position correction information to display (notify) the relative movement direction and movement amount required for correction, A user 202 such as a radiologist can accurately correct the imaging position based on the display (notification) result. As a result, it is possible to reduce the number of times the X-ray image capturing and the capturing position correction are repeated. As a result, it is possible to provide the X-ray imaging apparatus 100 and the imaging position correction method that are capable of obtaining X-ray images that enable accurate diagnosis while suppressing increases in exposure dose and imaging time. . Further, by performing control to change the relative position of the X-ray irradiation unit 1 using the acquired position correction information, the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 can be changed to a plurality of positions. The positional relationship between the outer edges of the predetermined portion can be accurately corrected to a position at which an X-ray image captured in a predetermined positional relationship suitable for diagnosis can be captured. As a result, it is possible to reduce the number of times the X-ray image capturing and the capturing position correction are repeated. As a result, it is possible to provide the X-ray imaging apparatus 100 and the imaging position correction method that are capable of obtaining X-ray images that enable accurate diagnosis while suppressing increases in exposure dose and imaging time. .

Further, the X-ray imaging apparatus 100 according to the first embodiment can obtain the following further effects by being configured as follows.

In the first embodiment, the X-ray imaging apparatus 100 is configured to display (notify) the position correction information acquired by the processing section 81 (correction information acquisition section). Accordingly, by displaying (notifying) the position correction information acquired by the processing unit 81, the user 202 can set the relative position of the X-ray irradiation unit 1 with respect to the bones (imaging object) of the subject 201 in a plurality of predetermined positions. It is possible to grasp the relative movement direction and movement amount for correcting the X-ray image in which the positional relationship between the outer edges of the parts is a predetermined positional relationship to a position where the image can be taken. As a result, the user 202 can determine the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 to a position where an X-ray image can be captured in which the outer edges of a plurality of predetermined portions are captured in a predetermined positional relationship. can be easily corrected to The X-ray imaging apparatus 100 is also configured to perform control for changing the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 based on the position correction information. As a result, the X-ray imaging apparatus 100 performs control for changing the position of the X-ray irradiation unit 1 relative to the bones of the subject 201 based on the position correction information. The relative position of the X-ray irradiator 1 can be easily corrected to a position where an X-ray image in which the outer edges of a plurality of predetermined portions are captured in a predetermined positional relationship can be captured.

Further, in the first embodiment, the device control unit 7 (movement control unit) controls the movement of the object by the irradiation unit movement mechanism 4 (movement mechanism) based on the position correction information acquired by the processing unit 81 (correction information acquisition unit). It is configured to control changes in the relative position of the X-ray irradiation unit 1 with respect to the bones (imaging object) of the subject 201 . As a result, the device control unit 7 controls the relative position change of the X-ray irradiation unit 1 with respect to the bones of the subject 201 by the irradiation unit moving mechanism 4 based on the position correction information. Based on this, it is possible to correct the photographing position more easily than when the user 202 performs manual correction.

Further, in the first embodiment, the device control unit 7 (movement control unit) moves the bones (imaging object) of the subject 201 based on the position correction information acquired by the processing unit 81 (correction information acquisition unit). The position of the X-ray irradiation unit 1 is set so that the relative position of the X-ray irradiation unit 1 is such that an X-ray image in which the outer edges of a plurality of predetermined portions are captured in a predetermined positional relationship can be captured. Control to move automatically. As a result, the position of the X-ray irradiation unit 1 is automatically corrected by the device control unit 7, so compared to the case where the position of the X-ray irradiation unit 1 is corrected manually by the user 202, the X-ray irradiation unit 1 Correction of the position of the radiation unit 1 can be performed more easily.

Further, in the first embodiment, the apparatus control unit 7 (movement control unit) controls the position acquired by the processing unit 81 (correction information acquisition unit) when the X-ray irradiation unit 1 is moved based on the operation of the user 202. Based on the correction information, control is performed to limit the movement of the X-ray irradiation unit 1 . Accordingly, even when the user 202 manually operates the movement of the X-ray irradiation unit 1 to correct the imaging position, the movement of the X-ray irradiation unit 1 is restricted by the device control unit 7 based on the position correction information. be done. As a result, when the user 202 manually operates the X-ray irradiation unit 1 to move the X-ray irradiation unit 1 to correct the imaging position, the manual operation by the user 202 causes the X-ray irradiation unit 1 to move beyond the amount of movement necessary for correction. can be prevented from moving, and from moving the X-ray irradiation unit 1 in a direction other than the movement direction requiring correction.

Further, in the first embodiment, the display unit 91 displays the positional relationship between the outer edges of a plurality of predetermined portions in a predetermined positional relationship as notification of the positional correction information acquired by the processing unit 81 (correction information acquiring unit). The direction and amount of movement of the X-ray irradiation unit 1 relative to the bones of the subject 201 (object to be imaged) for correcting the X-ray image to an imageable position are displayed. As a result, the user 202 can visually confirm the relative moving direction and moving amount of the X-ray irradiation unit 1 with respect to the bones of the subject 201 displayed on the display unit 91, thereby making it possible to correct the imaging position in which direction. It is possible to easily grasp whether or not it is necessary to perform degree correction, and to manually correct the photographing position.

In addition, in the first embodiment, the processing unit 81 (correction information acquisition unit) is configured based on the positional relationship between the outer edges of a plurality of predetermined portions of one bone (imaging object) of the subject 201 in the X-ray image. obtaining relative positional deviations between outer edges of a plurality of predetermined portions in the X-ray image, and obtaining position correction information based on the obtained relative positional deviations between outer edges of the plurality of predetermined portions; is configured as As a result, since the relative positional deviation between the outer edges of the plurality of predetermined portions in the X-ray image is acquired, the relative positional deviation between the outer edges of the plurality of predetermined portions in the X-ray image and the plurality of predetermined portions The position correction information can be acquired based on the comparison with the relative positional deviation between the outer edges of the plurality of predetermined portions when the positional relationship between the outer edges of the plurality of predetermined portions is in a predetermined positional relationship.

Further, in the first embodiment, the processing unit 81 (correction information acquisition unit) calculates the outer edges of the plurality of predetermined portions based on how the outer edges of the plurality of predetermined portions of the bones of the subject 201 overlap in the X-ray image. Get the relative displacement between them. Then, when the knee side of the femur 31 of the subject 201 is imaged, the processing unit 81 generates an X-ray image in which the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b (the outer edges of a plurality of predetermined portions) overlap each other. position correction information for correcting the relative position of the X-ray irradiation unit 1 with respect to the subject 201 so that the X-ray irradiation unit 1 can be imaged. As a result, when imaging the knee side (around the knee joint) of the femur 31 of the subject 201, the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b (outer edges of a plurality of predetermined portions) are determined according to the position correction information. The relative position of the X-ray irradiation unit 1 with respect to the bone of the subject 201 is corrected to a position where an X-ray image in which the . As a result, it is possible to take an X-ray image that can accurately identify diseases that occur around the knee joint, such as osteochondritis dissecans and osteoarthritis of the knee.

Further, in the first embodiment, the processing unit 81 (correction information acquisition unit) calculates the outer edges of the plurality of predetermined portions based on the positional relationship between the outer edges of the plurality of predetermined portions in the bone of the subject 201 in the X-ray image. Get the relative displacement between them. Then, when imaging the elbow side of the humerus 36 of the subject 201, the processing unit 81 generates an X-ray image in which the outer edges of a plurality of predetermined portions (portions A, B, and C) of the humerus 36 appear concentrically. Position correction information is calculated for correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 to a position where imaging is possible. As a result, a plurality of predetermined portions (portions A, B, and C) of the humerus 36 are captured concentrically according to the position correction information when imaging the elbow side (around the elbow joint) of the humerus 36 of the subject 201. The relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 is corrected to a position where an X-ray image can be captured. As a result, it is possible to take an X-ray image that can accurately identify diseases that occur around the elbow joint, such as osteochondritis dissecans and elbow osteoarthritis.

Further, in the first embodiment, the processing unit 81 (correction information acquisition unit) corrects the relative position of the X-ray irradiation unit 1 with respect to the bones (imaging object) of the subject 201, and then corrects the X-ray image. A subject in a pre-shot image 24 (image before position correction), which is an X-ray image generated based on X-ray irradiation with a radiation dose smaller than that at the time of capturing the main shot image 23 (image after position correction) It is configured to acquire position correction information based on the positional relationship between outer edges of a plurality of predetermined portions of bone 201 . As a result, it is possible to reduce the exposure dose of the subject 201 in the imaging before the imaging position correction, thereby preventing an increase in the exposure dose of the subject 201 until an X-ray image that enables accurate diagnosis is acquired. can be suppressed more.

Further, in the first embodiment, the processing unit 81 (correction information acquisition unit) inputs X-ray images to the learned models 82a and 82b (learned models 82c, 82d and 82e), thereby Outer edges of a plurality of predetermined portions are acquired based on the obtained X-ray image, and position correction information is calculated based on the acquired outer edges of the plurality of predetermined portions. As a result, the outer edges of a plurality of predetermined portions are acquired by the learned models 82a and 82b (learned models 82c, 82d and 82e), and the position correction information is calculated based on the acquired outer edges of the plurality of predetermined portions. Therefore, by using a trained model in which feature points of a region to be observed are learned, outer edges of a plurality of predetermined portions can be obtained with high accuracy. As a result, it is possible to accurately calculate the position correction information.

[Second embodiment]
A second embodiment will be described with reference to FIGS. 20 and 21. FIG. In the second embodiment, the processing unit 681 sets the slope α of the function f(x) of the X-ray tube position x based on the parameter information acquired from the pre-shot image 24, and calculates the position correction information. be done. In addition, in the figure, the same code|symbol is attached|subjected to the part of the structure similar to the said 1st Embodiment.

(Configuration of X-ray imaging apparatus according to the second embodiment)
As shown in FIG. 20, the X-ray imaging apparatus 600 includes a processing device 608 . The processing device 608 includes a processing section 681 . The processing device 608 is, for example, a PC operated by the user 202 such as a radiologist, like the processing device 8 of the first embodiment. The processing unit 681 includes a CPU, a GPU, a RAM, and the like, like the processing unit 81 of the first embodiment. The processing unit 681 is an example of a "correction information acquisition unit" in the scope of claims. In the second embodiment, for example, the X-ray imaging apparatus 600 performs X-ray imaging of the knee of the subject 201 .

As with the processing unit 81 of the first embodiment, the processing unit 681 detects the outer edge of the medial condyle 31a and the lateral condyle of the femur 31 from the pre-shot image 24 when imaging the knee side of the femur 31 of the subject 201. A deviation (amount of deviation and direction of deviation) from the outer edge of 31b is calculated. Then, based on the calculated deviation between the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b of the femur 31, the processing unit 681 performs imaging at the imaging position where the outer edges of the medial condyle 31a and the lateral condyle 31b overlap each other. As described above, the moving direction and moving amount (moving distance) of the X-ray irradiation unit 1 are calculated as position correction information. At this time, as in the first embodiment, the processing unit 681 estimates the position (the position where the shift amount f becomes 0) at which an X-ray image in which the outer edges of the medial condyle 31a and the lateral condyle 31b are overlapped can be captured. The estimated position x′ is calculated from the deviation amount f ₁ between the outer edge of the medial condyle 31a and the outer edge of the lateral condyle 31b calculated from the pre-shot image 24, and the slope of the function f(x) of the X-ray tube position x is calculated by the following formula (1) (see FIG. 8) based on α.

ここで、ＳＩＤは、装置パラメータであるＸ線管球の縦軸位置であって、検出部２（Ｘ線検出部２１およびＸ線検出部２２）の検出面からＸ線照射部１までの距離である。ＳＩＤは、撮影の対象となる体の部位などに応じて推奨される値が自動的に設定されてもよいし、装置制御部７から実際の値を取得してもよい。また、ｂは、検出面から外側顆３１ｂまでの高さを示している。Ｄは、被検体２０１における内側顆３１ａと外側顆３１ｂとの実際の距離を示している。θは、検出面からの垂線に対する内側顆３１ａと外側顆３１ｂとを結んだ直線の傾きを示している。高さｂ、距離Ｄ、および、角度θは、被検体固有パラメータである。高さｂおよび距離Ｄは、被検体２０１の体格（骨の大きさ）に応じて変化する体格由来のパラメータである。角度θは、被検体２０１の姿勢に応じて変化する姿勢由来のパラメータである。第２実施形態の処理部６８１は、プレショット画像２４から体格由来のパラメータを自動的に算出する。すなわち、傾きαの値が、プレショット画像２４に基づいて自動的に算出される。 Here, the slope α varies depending on various parameters including apparatus parameters such as SID (Source to image receptor distance) and subject-specific parameters set corresponding to the subject 201 (patient) at the time of imaging. Specifically, the slope α is calculated by the following equation (2).

Here, SID is the vertical axis position of the X-ray tube, which is an apparatus parameter, and is the distance from the detection surface of the detection unit 2 (X-ray detection unit 21 and X-ray detection unit 22) to the X-ray irradiation unit 1. is. For the SID, a recommended value may be automatically set according to the part of the body to be imaged, or an actual value may be acquired from the apparatus control section 7 . Also, b indicates the height from the detection surface to the lateral condyle 31b. D indicates the actual distance between the medial condyle 31a and the lateral condyle 31b in the subject 201; θ indicates the inclination of a straight line connecting the medial condyle 31a and the lateral condyle 31b with respect to a perpendicular line from the detection surface. Height b, distance D, and angle θ are subject-specific parameters. The height b and the distance D are physique-derived parameters that change according to the physique (size of bones) of the subject 201 . The angle θ is a posture-derived parameter that changes according to the posture of the subject 201 . The processing unit 681 of the second embodiment automatically calculates parameters derived from physique from the pre-shot image 24 . That is, the value of the slope α is automatically calculated based on the pre-shot image 24 .

In the second embodiment, the processing unit 681 corresponds to the actual distance between the medial condyle 31a and the lateral condyle 31b (a plurality of predetermined portions) of the bone (imaging object) of the subject 201 in order to calculate the inclination α. Position correction information is calculated based on the parameter information. The processing unit 681 detects the size of the detection target portion of the subject 201 in the X-ray image of the subject 201 as parameter information. Specifically, the processing unit 681 detects, as the parameter information, the size of the detection target portion of the subject 201 from the pre-shot image 24, which is an X-ray image taken to acquire the position correction information. do. Then, the processing unit 681 calculates the position correction information by calculating the height b and the distance D based on the detected parameter information.

As shown in FIG. 21 , detection target portions of the subject 201 are, for example, portions 31 c and 31 d of the femur 31 and a portion 32 c of the tibia 32 of the subject 201 . In the second embodiment, the detection target portions (the portions 31c, 31d, and 32c) of the subject 201 whose sizes are detected as the parameter information are the subject 201 to be imaged in a predetermined positional relationship. is different from the plurality of predetermined portions (the medial condyle 31a and the lateral condyle 31b) of the object to be photographed. A detection target portion is a portion having a correlation in size or shape with a predetermined portion.

For example, the processing unit 681 performs segmentation processing using an algorithm such as a pre-stored learned model, thereby extracting the portions 31 c and 31 d of the femur 31 of the subject 201 and the tibia 32 from the pre-shot image 24 . The size (width) of each portion 32c is detected as parameter information. For example, the processing unit 681 detects contour lines of each of the femur 31 and the tibia 32 in the pre-shot image 24 using the learned model. Then, the processing unit 681 detects the size (the number of pixels) of the widths of the portions 31c, 31d, and 32c from the detected contour lines, thereby determining the size of the detection target portion of the subject 201. To detect. The positions of the portion 31c, the portion 31d, and the portion 32c in the preshot image 24 may be extracted from the shape of the outline, the positional coordinates, or the like, or may be obtained based on the input operation by the user 202. good.

Then, the processing unit 681 calculates the position correction information from the sizes of the portions 31c, 31d, and 32c detected as parameter information, for example, by referring to a preset data table. Calculate the value of the height b and the distance D of . In the preset data table, the size of each of the portions 31c and 31d of the femur 31 and the portion 32c of the tibia 32 of the subject 201, the height b from the detection surface to the lateral condyle 31b, and The actual distance D between the medial condyle 31a and the lateral condyle 31b is associated and stored. That is, the processing unit 681 acquires the sizes of the portions 31c and 31d of the femur 31 and the portion 32c of the tibia 32 of the subject 201, which are the detection target portions detected as the parameter information. A height b and a distance D, which are parameters derived from the physique peculiar to 201, are calculated.

By using the height b and the distance D obtained in this way, the processing unit 681 calculates the value of the slope α by the above equation (2). Note that the angle θ, which is a parameter derived from the posture, may be automatically set to a recommended value according to the part of the body to be imaged, or the posture of the subject 201 may be determined using an optical camera or the like. You may make it detect a value by detecting . Then, the processing unit 681 calculates the estimated position x′ according to the above equation (1) using the slope α reflecting the parameter derived from the physique, thereby obtaining Then, the position correction information is calculated.

Other configurations of the X-ray imaging apparatus 600 according to the second embodiment are the same as those of the first embodiment. That is, acquisition of the pre-shot image 24, acquisition of the deviation amount _f1 from the pre-shot image 24, and position correction processing based on the calculated position correction information are the same as in the first embodiment.

(Photographing position correction method according to the second embodiment)
Next, with reference to FIG. 22, the processing flow of the imaging position correction method of the X-ray imaging apparatus 600 according to the second embodiment will be described. FIG. 22 illustrates the processing flow of position correction using the automatic correction mode.

First, in steps 701 and 702, the same processes as steps 301 and 302 in the first embodiment are performed, respectively. Then, after step 702 is completed, the processing steps transition to step 703 . Note that step 701 is an example of the "irradiation step" in the scope of claims. Also, step 702 is an example of a "detection step" in the claims.

In step 703, parameter information corresponding to the actual distance between the medial condyle 31a and the lateral condyle 31b (a plurality of predetermined portions) in the bone (imaging object) of the subject 201 is obtained. Specifically, as the parameter information, the size of each of the portions 31c and 31d of the femur 31 and the portion 32c of the tibia 32 (detection target portions) is detected from the pre-shot image 24 captured in step 702. be.

Then, in step 704, position correction information is calculated based on the parameter information. Specifically, the height b and the distance D are obtained based on the sizes of the portions 31c and 31d of the femur 31 and the portion 32c of the tibia 32 obtained as parameter information. Then, by calculating the inclination α based on the acquired height b and distance D, the position correction information is obtained. Note that step 704 is an example of the "correction information acquisition step" in the scope of claims.

Then, in step 705, automatic position correction is performed as in step 304 of the first embodiment. Note that step 704 is an example of a "position correction step" in the scope of claims.

When performing position correction processing using the manual correction mode, as in the first embodiment, the same processing as in steps 701, 702, 703, and 704 in the automatic correction mode is performed. After the position correction information is acquired, the position correction information is displayed as in step 404 of the first embodiment, and manual position correction is performed as in step 405 .

(Effect of Second Embodiment)
The following effects can be obtained in the second embodiment.

The processing unit 681 (correction information acquisition unit) calculates the positions based on the parameter information corresponding to the actual distances between the plurality of predetermined portions (the medial condyle 31a and the lateral condyle 31b) in the bone (imaging object) of the subject 201. It is configured to calculate correction information. With this configuration, even if the actual distance between the predetermined portions of the bones of the subject 201 differs due to the difference in bone size and shape for each subject 201, the actual distance between the predetermined portions may differ. By calculating the position correction information based on the parameter information corresponding to the distance, the position correction information can be calculated more accurately. Therefore, the acquired position correction information can be used to correct the imaging position with higher accuracy, so that the number of repetitions of X-ray image imaging and imaging position correction can be further reduced. As a result, it is possible to further suppress increases in exposure dose and imaging time in X-ray imaging.

The processing unit 681 (correction information acquisition unit) obtains, as parameter information, the detection target portions of the subject 201 (the portions 31c and 31d of the femur 31 and the portion 32c of the tibia 32) in the X-ray image of the subject 201. Detect size. With this configuration, by detecting the size of the detection target portion as parameter information from the X-ray image of the subject 201, the size and shape of the femur 31 and the tibia 32, which are internal structures of the subject 201, can be detected. Parameter information can be obtained to more accurately reflect the difference in . Therefore, by acquiring the position correction information using the parameter information detected from the X-ray image of the subject 201, it is possible to more accurately acquire the relative movement direction and movement amount necessary for correcting the imaging position. can. As a result, the shooting position can be corrected more accurately.

The processing unit 681 (correction information acquisition unit) selects a detection target portion (femur 31 portion 31c, portion 31d, and portion 32c of the tibia 32). With this configuration, the parameter information can be obtained by using the pre-shot image 24 photographed to obtain the position correction information. Unlike the case where X-ray imaging is performed separately, it is possible to suppress an increase in the dose of X-rays irradiated to the subject 201 . Therefore, by acquiring the parameter information from the pre-shot image 24, it is possible to correct the imaging position more accurately, and to further suppress increases in the exposure dose and imaging time in X-ray imaging.

Other effects of the second embodiment are the same as those of the first embodiment.

[Third Embodiment]
A third embodiment will be described with reference to FIGS. 23 and 24. FIG. In the third embodiment, the processing unit 681 selects detection target portions of the subject 201 (the portions 31c and 31d of the femur 31, and the portions of the tibia 32) from the preshot image 24 as the parameter information for setting the inclination α. Unlike the second embodiment in which the size of the portion 32c) is detected, parameter information for setting the inclination α is obtained based on the appearance image 25. FIG. In addition, in the figure, the same reference numerals are given to the parts having the same configuration as those of the first and second embodiments.

(Configuration of X-ray imaging apparatus according to the third embodiment)
As shown in FIG. 23, the X-ray imaging apparatus 800 has a processing device 808 . The processing device 808 includes a processing section 881 . The processing device 808 is, for example, a PC operated by the user 202 such as a radiologist, like the processing device 608 of the second embodiment. The processing unit 881 includes a CPU, a GPU, a RAM, and the like, like the processing unit 681 of the second embodiment. The processing unit 881 is an example of a "correction information acquisition unit" in the scope of claims. The processing unit 881 automatically calculates the slope α by the above equation (2), like the processing unit 681 of the second embodiment. In the third embodiment, for example, X-ray imaging of the knee of the subject 201 is performed by the X-ray imaging apparatus 800 .

In the third embodiment, an X-ray imaging apparatus 800 includes an imaging section 811 and an image processing section 812 . The imaging unit 811 images the appearance of the subject 201 . The imaging unit 811 is arranged in the X-ray irradiation unit 1, for example. The imaging unit 811 images the subject 201 lying on the tabletop 3 along the irradiation direction of the X-rays emitted from the X-ray irradiation unit 1 . Also, the imaging unit 811 includes an image sensor (imaging device) such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). Image processing unit 812 includes a processor such as a CPU or FPGA, for example. The image processing unit 812 also includes a non-volatile storage medium such as an HDD or SSD that stores various parameters and programs. The image processing unit 812 acquires the appearance image 25 (see FIG. 24) of the appearance of the subject 201 by acquiring the signal from the imaging unit 811 . The image processing unit 812 is a module provided separately from the processing unit 881 . The image processing unit 812 is arranged in the X-ray irradiation unit 1 together with the imaging unit 811, for example. The image processing unit 812 is configured to be able to communicate with the processing unit 881 .

Then, as shown in FIG. 24, in the third embodiment, the image processing unit 812 uses the subject 201 acquired by imaging by the imaging unit 811 as parameter information for calculating the inclination α in the above equation (2). physique information indicating the size of the physique of the subject 201 is calculated from the appearance image 25 of FIG. Specifically, the image processing unit 812 calculates the length of the leg of the subject 201 as the physique information. The image processing unit 812 detects the lengths of the portions 201 a and 201 b of the leg of the subject 201 from the appearance image 25 acquired based on the signal from the imaging unit 811 . The portion 201a is the portion from the base of the leg of the subject 201 to the knee. The portion 201b is the portion of the leg of the subject 201 from the knee to the toe. The image processing unit 812 extracts the leg portions 201a and 201b of the subject 201 from the external image 25 using, for example, a trained model stored in advance in a storage medium. and the length of portion 201b. Thereby, the image processing unit 812 detects the physique information indicating the length of the leg of the subject 201 from the appearance image 25 as the parameter information.

Then, similarly to the processing unit 681 of the second embodiment, the image processing unit 812, for example, refers to the data table preset in the storage medium, thereby determining the leg part of the subject 201 detected as the parameter information. From the physique information indicating the length of , the values of the height b and the distance D for calculating the position correction information are calculated. In the preset data table, the physique information, the height b from the detection surface to the lateral condyle 31b, and the actual distance D between the medial condyle 31a and the lateral condyle 31b are associated and stored. there is That is, in the third embodiment, the image processing unit 812 calculates the height b and the distance D, which are parameters derived from the physique specific to the subject 201, by acquiring physique information as parameter information. Then, in the second embodiment, the height b and the distance D calculated by the image processing unit 812 are output to the processing unit 881 of the processing device 808 .

By using the height b and the distance D obtained in this way, the processing unit 881 calculates the value of the slope α by the above equation (2), similarly to the processing unit 681 of the first embodiment, By calculating the estimated position x′ using the above equation (1), the position correction information corresponding to the size and shape of the bone, which differs from object 201 to object 201, is calculated. That is, in the third embodiment, the processing unit 881 is configured to calculate position correction information based on parameter information, which is physique information calculated from the appearance image 25 by the image processing unit 812 .

Other configurations of the X-ray imaging apparatus 800 according to the third embodiment are the same as those of the first and second embodiments.

(Effect of the third embodiment)
The following effects can be obtained in the third embodiment.

The third embodiment includes an imaging unit 811 that captures the appearance of the subject 201 . Then, the processing unit 881 (correction information acquisition unit) converts parameter information, which is physique information indicating the size of the physique of the subject 201 calculated from the appearance image 25 of the subject 201 acquired by imaging by the imaging unit 811. Based on this, the position correction information is calculated. With this configuration, it is possible to acquire the parameter information, which is the physique information indicating the physique size of the subject 201 , based on the appearance image 25 . Information can be obtained. Therefore, it is possible to more accurately acquire the relative moving direction and moving amount necessary for correcting the imaging position so as to correspond to the physical size of the subject 201, so that the imaging position can be corrected more accurately. It can be carried out.

Other effects of the third embodiment are the same as those of the first and second embodiments.

[Fourth embodiment]
A fourth embodiment will be described with reference to FIGS. 25 and 26. FIG. In the fourth embodiment, unlike the second embodiment in which the processing unit 681 acquires the parameter information from the pre-shot image 24, the processing unit 981 acquires the parameter information separately from the pre-shot image 24 in advance. Parameter information for setting the inclination α is acquired based on the front image 26, which is an X-ray image obtained by the imaging. In the drawings, the same reference numerals are given to the same parts as those of the first to third embodiments.

(Configuration of X-ray imaging apparatus according to the fourth embodiment)
As shown in FIG. 25, the X-ray imaging apparatus 900 has a processing device 908 . The processing device 908 includes a processing section 981 . The processing device 908 is, for example, a PC operated by the user 202 such as a radiologist, like the processing device 608 of the second embodiment. The processing unit 981 includes a CPU, a GPU, a RAM, and the like, like the processing unit 681 of the second embodiment. The processing unit 981 automatically calculates the slope α by the above equation (2), like the processing unit 681 of the second embodiment. Note that the processing unit 981 is an example of a "correction information acquisition unit" in the scope of claims. In the fourth embodiment, for example, the X-ray imaging apparatus 900 performs X-ray imaging of the knee of the subject 201 .

As shown in FIG. 26, in the fourth embodiment, the processing unit 981 is an X-ray image captured in advance at an imaging angle different from the pre-shot image 24, which is an X-ray image for acquiring position correction information. A front image 26 is acquired. Then, the processing unit 981 detects the size of the detection target portion of the subject 201 from the front image 26 as parameter information for calculating the inclination α. Specifically, the front image 26 is an X-ray image of the knee of the subject 201 previously captured from the front side separately from the pre-shot image 24 of the knee of the subject 201 captured from the lateral side. The front image 26 is captured before the pre-shot image 24 and stored in advance in the storage unit 82 . The detection target portion of the subject 201 detected from the front image 26 is the portion 31e from the medial condyle 31a to the lateral condyle 31b of the femur 31 of the subject 201, and the portion 31e of the subject 201 from the lateral condyle 31b. The midline side is the portion 31f up to the skin on the opposite side. Therefore, in the fourth embodiment, the detection target portion of the subject 201 whose size is detected as the parameter information is a plurality of predetermined portions of the object to be imaged of the subject 201 that is to be imaged in a predetermined positional relationship. be.

The processing unit 981 detects the positions of the medial condyle 31a and the lateral condyle 31b from the front image 26 captured in advance before the pre-shot image 24 is captured. For example, the processing unit 981 extracts the contour of the femur 31 by segmentation processing using a pre-stored learned model, and extracts the extracted contour of the femur 31 at the medial condyle 31a that is closest to the tibia 32. and the portion of the lateral condyle 31b closest to the tibia 32 are detected as the positions of the medial condyle 31a and the lateral condyle 31b, respectively. Then, the processing unit 981 detects the size (distance) from the position of the medial condyle 31a to the position of the lateral condyle 31b as the size of the portion 31e of the subject 201, which is the detection target portion. Similarly, by detecting the position of the skin of the subject 201 in the front image 26, the processing unit 981 determines the size (distance) from the position of the lateral condyle 31b to the position of the skin. It is detected as the size of the portion 31f, which is the target portion. Here, the size of the portion 31e corresponds to the actual distance D between the medial condyle 31a and the lateral condyle 31b. Also, the size of the portion 31f corresponds to the height b from the detection surface to the lateral condyle 31b. That is, in the fourth embodiment, the processing unit 981 directly detects the values of the height b and the distance D as the parameter information from the front image 26 separately photographed at a photographing angle different from that of the pre-shot image 24. do.

Then, similarly to the processing unit 681 of the second embodiment, the processing unit 981 calculates the height b (the size of the portion 31f) from the detection surface detected as the parameter information to the lateral condyle 31b, and the medial condyle 31a. By using the actual distance D (the size of the portion 31e) from the lateral condyle 31b, the value of the slope α is calculated by the above equation (2), and the estimated position x' is calculated by the above equation (1). , the position correction information corresponding to the size and shape of the bone, which differs for each subject 201, is calculated.

Other configurations of the X-ray imaging apparatus 900 according to the fourth embodiment are the same as those of the first to third embodiments.

(Effect of the fourth embodiment)
The following effects can be obtained in the fourth embodiment.

The processing unit 981 (correction information acquisition unit) obtains, as parameter information, the front image 26, which is an X-ray image captured in advance at an imaging angle different from the pre-shot image 24, which is an X-ray image for acquiring position correction information. Among them, the size of the detection target portion (the portion 31e and the portion 31f) of the subject 201 is detected. With this configuration, the size of the detection target portion can be detected from the X-ray image (front image 26) taken at an imaging angle different from the X-ray image (pre-shot image 24) for correcting the position. , the positional relationship between a plurality of predetermined portions (the medial condyle 31a and the lateral condyle 31b) can be detected from an imaging angle different from that of the pre-shot image 24. FIG. Therefore, it is possible to acquire more accurate position correction information based on the positional relationship between the plurality of predetermined portions taken from different shooting angles than the pre-shot image 24 .

Other effects of the fourth embodiment are the same as those of the first to third embodiments.

[Modification]
It should be noted that the embodiments disclosed this time should be considered as examples and not restrictive in all respects. The scope of the present invention is indicated by the scope of claims rather than the description of the above-described embodiments, and includes all modifications (modifications) within the scope and meaning equivalent to the scope of claims.

For example, in the above-described first to fourth embodiments, the processing units 81, 681, 881, and 981 (correction information acquisition units) determine the positional relationship between the outer edges of a plurality of predetermined portions of the bones of the subject 201 in the X-ray image. Although an example configured to acquire the position correction information for correcting the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 is shown, the present invention is not limited to this. . In the present invention, the correction information acquisition unit calculates the relative position of the X-ray irradiation unit with respect to the artificial joint of the subject based on the positional relationship between the outer edges of a plurality of predetermined portions of one artificial joint of the subject in the X-ray image. It may also be configured to acquire position correction information for correcting the position of the object. Further, the correction information acquisition unit of the X-ray imaging apparatus may be configured to acquire the position correction information both when imaging the bone and when imaging the artificial joint. The artificial joint is an example of the "imaging object" in the scope of claims.

In addition, in the above-described first to fourth embodiments, the position correction information acquired by the processing units 81, 681, 881, and 981 (correction information acquisition units) is displayed, and the bone of the subject 201 is displayed based on the position correction information. Although an example of performing control for changing the relative position of the X-ray irradiation unit 1 with respect to is shown, the present invention is not limited to this. In the present invention, the X-ray imaging apparatus may only notify the position correction information acquired by the correction information acquisition section. In this case, a user such as a radiologist manually corrects the imaging position based on the notified position correction information. Further, the correction of the position of the X-ray irradiation unit relative to the bone or artificial joint (imaging object) of the subject may be performed by the user moving the subject or by the subject moving. Further, the X-ray imaging apparatus may be configured to automatically correct the imaging position without notifying the position correction information acquired by the correction information acquisition unit.

Further, in the first to fourth embodiments described above, the device control unit 7 (movement control unit), based on the position correction information acquired by the processing units 81, 681, 881, and 981 (correction information acquisition unit), X-ray irradiation is performed so that the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201 is such that an X-ray image in which the outer edges of a plurality of predetermined portions are captured in a predetermined positional relationship can be captured. Although an example of automatically moving the position of the unit 1 has been shown, the present invention is not limited to this. In the present invention, when correcting the position of the X-ray irradiator relative to the bone or artificial joint (imaging object) of the subject, both the X-ray irradiator and the table on which the subject is placed are The shooting position may be corrected by moving automatically. Also, when correcting the relative position of the X-ray irradiation unit with respect to the subject's bones or artificial joints (imaging object), only the top plate on which the subject is placed is automatically moved, Positional corrections may be made.

Further, in the first to fourth embodiments, the device control unit 7 (movement control unit) controls the processing units 81, 681, 881, 981 ( Although an example of performing control to limit the movement of the X-ray irradiation unit 1 based on the position correction information acquired by the correction information acquisition unit) has been shown, the present invention is not limited to this. In the present invention, the X-ray imaging apparatus may be configured not to restrict the movement of the X-ray irradiation unit while the user is operating it. Further, the X-ray imaging apparatus may be configured to restrict movement of the X-ray irradiation unit and release the restriction of movement based on user's operation. Further, in the present invention, the movement control unit moves the table on which the subject is placed based on the user's operation, based on the position correction information acquired by the correction information acquisition unit. Control may be performed to limit the movement of the tabletop on which it is placed. For example, the movement control unit may limit the movement of the tabletop by the moving mechanism by controlling the movement of the tabletop to be locked by a brake. As a result, even when the imaging position is corrected by the user manually moving the table on which the subject is placed, the table on which the subject is placed can be moved based on the position correction information. is limited by the movement control. As a result, when the imaging position is corrected by the user's manual operation of moving the tabletop on which the subject is placed, the user's manual operation causes the subject to move beyond the amount of movement necessary for correction. It is possible to prevent the top plate on which the subject is placed from moving and the top plate on which the subject is placed from moving in a direction other than the direction of movement that requires correction.

In addition, in the above-described first to fourth embodiments, the display unit 91 notifies the processing unit 81 (681, 881 , 981) to display the relative movement direction and movement amount of the X-ray irradiation unit 1 with respect to the bone of the subject 201 based on the relative positional deviation between the outer edges of a plurality of predetermined portions obtained by Although shown, the invention is not so limited. In the present invention, the display unit may display only the relative movement direction of the X-ray irradiation unit among the relative movement direction and movement amount of the X-ray irradiation unit with respect to the bone of the subject. In this case, the X-ray imaging apparatus restricts the movement of the X-ray irradiation unit when the X-ray irradiation unit moved manually by the user reaches an appropriate imaging position acquired based on the position correction information. (locking) completes the correction of the photographing position.

Further, in the above-described first to fourth embodiments, in the radiography of the knee joint (knee side of the femur 31), the positions where the X-ray images in which the outer edges of a plurality of predetermined parts overlap with each other can be radiographed according to the position correction information. shows an example of correcting the relative position of the X-ray irradiation unit 1 with respect to the bone or artificial joint (imaging object) of the subject 201, but the present invention is not limited to this. In the present invention, as shown in FIG. 17, when performing imaging called scapula Y (scapula wye) in which the scapula 39 is photographed in a Y shape, the outer edges of a plurality of predetermined portions of the scapula 39 overlap each other, Position correction information for correcting the imaging position may be acquired to a position at which an X-ray image in which the scapula 39 appears in a Y shape can be captured. Then, based on the acquired position correction information, the position of the X-ray irradiation unit relative to the subject may be corrected. As a result, it is possible to take an X-ray image that can accurately identify diseases around the scapula 39 such as anterior dislocation, subacromial bone spur and calcification.

In addition, in the first to fourth embodiments, the X-ray imaging apparatus 100 (600, 800, 900) performs imaging of the knee joint (knee side of the femur 31) and elbow joint (knee side of the humerus 36). An example of calculating the position correction information and correcting the shooting position based on the position correction information at the time of shooting has been described, but the present invention is not limited to this. In the present invention, the X-ray imaging apparatus calculates position correction information when imaging other joints such as hip joints, finger joints, wrist joints and ankle joints, and other parts, and performs imaging based on the position correction information. It may be configured to provide positional corrections.

In addition, in the above-described first to fourth embodiments, the X-ray imaging apparatus 100 (600, 800, 900) has a knee joint (knee side of the femur 31) and an elbow joint (elbow side of the humerus 36). An example of acquiring position correction information during imaging, displaying (announcing) the acquired position correction information, and controlling a change in the relative position of the X-ray irradiation unit 1 based on the acquired position correction information. Although shown, the invention is not so limited. In the present invention, the X-ray imaging apparatus provides position correction information only when imaging the knee joint (on the knee side of the femur) or when imaging the elbow joint (on the elbow side of the humerus). It may be configured to acquire and report the acquired position correction information, or to control the change of the relative position of the X-ray irradiation unit based on the acquired position correction information. That is, the X-ray imaging apparatus acquires position correction information only for a specific imaging site, and notifies the acquired position correction information, or determines the relative position of the X-ray irradiation unit based on the acquired position correction information. Change control may be performed.

Further, in the first to fourth embodiments, the processing units 81, 681, 881, and 981 (correction information acquisition units) correct the relative position of the X-ray irradiation unit 1 with respect to the bones of the subject 201, and then perform imaging. A plurality of bones of the subject 201 in the pre-shot image 24 (image before position correction) generated based on X-ray irradiation with a radiation dose smaller than that at the time of capturing the main shot image 23 (image after position correction) Although an example has been shown in which the position correction information is acquired based on the positional relationship between the outer edges of the predetermined portion of the, the present invention is not limited to this. In the present invention, the image used by the correction information acquisition unit to acquire the position correction information is an X-ray image with a radiation dose higher than that at the time of capturing the image after position correction, which is captured after correcting the relative position of the X-ray irradiation unit. It may also be an X-ray image generated based on radiation exposure. In addition, the image used by the correction information acquisition unit to acquire the position correction information is an X-ray with a radiation dose equal to or greater than that of the position-corrected image captured after correcting the relative position of the X-ray irradiation unit. The X-ray image generated based on the irradiation may be an image after preprocessing as described in the first to fourth embodiments.

Further, in the first to fourth embodiments, the processing units 81, 681, 881, and 981 (correction information acquiring units) input X-ray images to the learned models 82a and 82b, thereby An example is shown in which the outer edges of a plurality of predetermined portions are acquired based on the obtained X-ray image, and the position correction information is calculated based on the acquired outer edges of the plurality of predetermined portions. It is not limited to this. In the present invention, acquisition (specification) of the outer edges of a plurality of predetermined portions such as the medial condyle and the lateral condyle of the femur used for calculating the amount of deviation is performed by an image processing algorithm that extracts the feature points of the outer edges of the plurality of predetermined portions. may be obtained (identified) by Also, when acquiring parameter information for acquiring parameters derived from the physique specific to the subject, an image processing algorithm that extracts feature points may be used instead of the trained model.

In addition, in the first to fourth embodiments, the processing units 81, 681, 881, and 981 (correction information acquiring units) acquire outer edges of a plurality of predetermined portions based on the input X-ray image, and acquire Although an example is shown in which the position correction information is calculated based on the outer edges of a plurality of predetermined portions, the present invention is not limited to this. In the present invention, the correction information acquisition unit acquires, in addition to the X-ray image, a visible light image of the subject captured by an optical camera that detects visible light, and a plurality of bones or artificial joints (imaging objects) of the subject. may be used to obtain the outer edge of a predetermined portion of the , and to calculate position correction information.

In addition, in the above-described first to fourth embodiments, the X-ray imaging apparatus 100 (600, 800, 900) switches between the automatic correction mode and the manual correction mode based on the switching operation of the user 202 for correcting the imaging position. Although an example configured to be switchable between modes has been shown, the present invention is not limited to this. In the present invention, the correction of the imaging position using the X-ray imaging apparatus may be performed by either automatic correction or manual correction.

Further, in the first to fourth embodiments, the X-ray imaging apparatus 100 (600, 800, 900) captures an X-ray image with X-rays emitted from the X-ray irradiation unit 1 suspended from the ceiling. Although an example configured to perform is shown, the present invention is not limited to this. As shown in FIG. 18, the present invention includes an irradiation unit support mechanism 504 extending along a direction (Z direction) intersecting the floor surface, and an X-ray irradiation unit 501 supported by the irradiation unit support mechanism 504. It may be applied to the line imaging device 500 . That is, the X-ray imaging apparatus captures an X-ray image with X-rays emitted from the X-ray irradiation unit 501 attached to the irradiation unit support mechanism 504 extending along the direction (Z direction) intersecting the floor surface. may be configured to do so. Further, in correcting the imaging position using the X-ray imaging apparatus 500, position correction information is displayed on the display unit 591 of the operation terminal 509 as shown in FIG. will be Note that the display unit 591 of the operation terminal 509 is provided with a touch panel for receiving input operations by the user 202 .

Further, in the above-described second to fourth embodiments, an example is shown in which the slope α, which is a coefficient for calculating position correction information, is calculated based on automatically acquired parameter information. It is not limited to this. In the present invention, the parameter information may be acquired based on the user's input operation. Further, the parameter information may be calculated from the X-ray image or the appearance image by a processing device different from the processing units 681, 881, and 981 (correction information acquiring units) that calculate the position correction information. Alternatively, parameter information set (stored) in advance may be acquired from an external device such as a server. The parameter information may also include the values of subject-specific parameters (such as height b and distance D) for calculating position correction information.

Further, in the second embodiment, the sizes of the portions 31c and 31d of the femur 31 of the subject 201 and the portion 32c of the tibia 32 of the subject 201 are used as the size of the detection target portion of the subject 201 as the parameter information. Although an example of detection has been shown, the present invention is not limited to this. In the present invention, the size of at least one of the portions 31c and 31d of the femur 31 and the portion 32c of the tibia 32 may be obtained as parameter information. Further, when X-ray imaging of the knee is performed, the size of portions other than the portions 31c, 31d, and 32c may be detected as the size of the detection target portion of the subject.

Further, in the above-described third embodiment, an example in which the physique information indicating the length of the leg of the subject 201 is acquired as parameter information has been described, but the present invention is not limited to this. In the present invention, the height of the entire body of the subject may be detected, and physique information indicating the detected height of the subject may be acquired as parameter information. Also, when X-ray imaging of an elbow joint is performed, physique information indicating arm length may be acquired as parameter information. Also, physique information indicating shoulder width, body thickness, etc. may be acquired as parameter information. Further, in the third embodiment, the image processing unit 812, which is a module different from the processing unit 881 (correction information acquisition unit) that calculates the position correction information, acquires the parameter information from the appearance image 25. Although an example has been shown, the correction information acquisition section may detect the physique information from the appearance image and acquire the parameter information by outputting the appearance image obtained by the imaging section to the correction information acquisition section.

Further, in the third embodiment, an example in which the subject 201 lying on the tabletop 3 is imaged by the imaging unit 811 arranged in the X-ray irradiation unit 1 has been described, but the present invention is not limited to this. In the present invention, the imaging unit may be arranged on the ceiling of the examination room instead of the X-ray irradiation unit. Further, the parameter information may be acquired by imaging the subject in a standing state instead of the subject lying on the tabletop.

In addition, in the above-described first to fourth embodiments, for convenience of explanation, the processing of correcting the imaging position (automatic correction and manual correction) using the X-ray imaging apparatus of the present invention is performed in order according to the processing flow. Although described using a flow-driven flow chart, the present invention is not limited to this. In the present invention, processing for correcting the imaging position using the X-ray imaging apparatus may be performed by event-driven processing that executes processing on an event-by-event basis. In this case, it may be completely event-driven, or a combination of event-driven and flow-driven.

[Aspect]
It will be appreciated by those skilled in the art that the exemplary embodiments described above are specific examples of the following aspects.

(Item 1)
an X-ray irradiation unit that irradiates X-rays to a subject;
an X-ray detection unit that detects X-rays emitted from the X-ray irradiation unit and transmitted through the subject;
identifying the outer edge of each of a plurality of predetermined portions of one imaging object of the subject in an X-ray image captured based on the detection signal of the X-ray detection unit, a correction information acquisition unit that acquires position correction information for correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the positional relationship between outer edges;
The position correction information is the relative position of the X-ray irradiation unit with respect to the imaging object of the subject, and the X-ray image in which the outer edges of the plurality of predetermined portions are captured in a predetermined positional relationship. An X-ray imaging apparatus including relative movement direction and movement amount for correction to an imageable position.

(Item 2)
Notification of the position correction information acquired by the correction information acquisition unit, and control for changing the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the position correction information The X-ray imaging apparatus according to item 1, configured to perform at least one of:

(Item 3)
a movement mechanism for changing the relative position of the X-ray irradiation unit with respect to the subject;
a movement control unit that controls change of the position of the X-ray irradiation unit relative to the subject by the movement mechanism;
The movement control unit controls change of the position of the X-ray irradiation unit relative to the imaging object of the subject by the movement mechanism based on the position correction information acquired by the correction information acquisition unit. 3. The radiographic apparatus according to item 2, configured to perform

(Item 4)
further comprising a top plate on which the subject is placed;
The movement control unit adjusts the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the position correction information acquired by the correction information acquisition unit. Control for automatically moving the position of at least one of the X-ray irradiator and the top plate so that the positional relationship between the outer edges becomes a position where the X-ray image captured in the predetermined positional relationship can be captured. The X-ray imaging apparatus according to item 3, wherein

(Item 5)
further comprising a top plate on which the subject is placed;
When one of the X-ray irradiation unit and the tabletop is moved based on a user's operation, the movement control unit controls the X-ray irradiation unit based on the position correction information acquired by the correction information acquisition unit. Alternatively, the X-ray imaging apparatus according to item 3, wherein control is performed to restrict movement of one of the top plates.

(Item 6)
As notification of the position correction information acquired by the correction information acquisition unit, the positional relationship between the outer edges of the plurality of predetermined portions is corrected to a position where the X-ray image captured in the predetermined positional relationship can be captured. Items 2 to 2, further comprising a display unit for displaying at least the relative movement direction of the X-ray irradiation unit among the relative movement direction and movement amount of the X-ray irradiation unit with respect to the imaging object of the subject. 6. The X-ray imaging apparatus according to any one of 5.

(Item 7)
The correction information acquisition unit is configured to obtain the plurality of predetermined portions in the X-ray image based on the positional relationship between the outer edges of the plurality of predetermined portions in the one imaging object of the subject in the X-ray image. Item 2, wherein relative positional deviation between outer edges is acquired, and the position correction information is acquired based on the acquired relative positional deviation between outer edges of the plurality of predetermined portions. 7. The X-ray imaging apparatus according to any one of 1 to 6.

(Item 8)
The correction information acquisition unit identifies the outer edge of each of the plurality of predetermined portions of the bone or artificial joint as one of the imaging objects of the subject in the X-ray image, and identifies the identified bone or artificial joint. The position correction information for correcting the relative position of the X-ray irradiation unit with respect to the bone or artificial joint of the subject is acquired based on the positional relationship between the outer edges of the plurality of predetermined portions in The X-ray imaging apparatus according to any one of items 2 to 7, wherein

(Item 9)
The correction information acquisition unit is configured to determine the degree of overlap between the outer edges of the plurality of predetermined portions in each of the bones or artificial joints of the subject in the X-ray image. a relative position of the X-ray irradiation unit with respect to the bones or artificial joints of the subject at a position where the X-ray image in which the outer edges of the plurality of predetermined portions overlap with each other can be captured. 9. The X-ray imaging apparatus according to item 8, configured to calculate the position correction information for correcting the .

(Item 10)
The correction information acquisition unit is capable of capturing the X-ray image in which the outer edges of the plurality of predetermined portions overlap each other when capturing at least one of the knee side of the femur and the scapula of the subject. The X-ray imaging apparatus according to item 9, configured to calculate the position correction information for correcting the position of the X-ray irradiation unit relative to the bone or artificial joint of the subject. .

(Item 11)
The correction information acquiring unit is configured to obtain a relative position between outer edges of the plurality of predetermined portions based on a positional relationship between outer edges of the plurality of predetermined portions in each of the bones or artificial joints of the subject in the X-ray image. a relative position of the X-ray irradiation unit with respect to the bones or artificial joints of the subject at a position where the X-ray image in which the outer edges of the plurality of predetermined portions appear concentrically can be captured. 11. The X-ray imaging apparatus according to any one of items 8 to 10, configured to calculate the position correction information for correcting the position.

(Item 12)
The correction information acquiring unit, when imaging the elbow side of the humerus of the subject, places the outer edges of the plurality of predetermined portions of the subject at a position where the X-ray image can be captured concentrically. 12. The X-ray imaging apparatus according to Item 11, configured to calculate the position correction information for correcting the relative position of the X-ray irradiation unit with respect to bones or artificial joints.

(Item 13)
The correction information acquisition unit receives less radiation than when the image after position correction, which is the X-ray image captured after correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject. Based on the positional relationship between the outer edges of the plurality of predetermined portions of the object to be imaged of the subject in the pre-position-corrected image, which is the X-ray image generated based on the irradiation of the amount of X-rays, the position 13. The radiographic apparatus according to any one of items 1 to 12, configured to acquire correction information.

(Item 14)
The correction information acquisition unit inputs the X-ray image to a learned model that has been machine-learned using the X-ray image obtained by imaging the imaging object as input data. any one of items 1 to 13, wherein outer edges of the plurality of predetermined portions are obtained based on and the position correction information is calculated based on the obtained outer edges of the plurality of predetermined portions. X-ray imaging apparatus according to.

(Item 15)
wherein the correction information acquisition unit is configured to calculate the position correction information based on parameter information corresponding to actual distances between the plurality of predetermined portions of the imaging object of the subject; 15. The X-ray imaging apparatus according to any one of 1 to 14.

(Item 16)
16. The X-ray imaging apparatus according to Item 15, wherein the correction information acquisition unit detects, as the parameter information, a size of a detection target portion of the subject in the X-ray image of the subject.

(Item 17)
Item 16, wherein the correction information acquisition unit detects, as the parameter information, the size of the detection target portion of the subject from the X-ray image taken to acquire the position correction information. The X-ray imaging device described.

(Item 18)
The correction information acquisition unit selects, as the parameter information, the detection target of the subject from among the X-ray images captured in advance at an imaging angle different from that of the X-ray image for acquiring the position correction information. 17. X-ray imaging apparatus according to item 16, for detecting the size of the part.

(Item 19)
Further comprising an imaging unit for imaging the appearance of the subject,
The correction information acquisition unit corrects the position based on the parameter information, which is physique information indicating the size of the physique of the subject calculated from the appearance image of the subject acquired by imaging by the imaging unit. 16. Radiography apparatus according to item 15, adapted to calculate information.

(Item 20)
an irradiation step of irradiating the subject with X-rays from the X-ray irradiation unit;
a detection step of detecting X-rays that have passed through the subject;
identifying the outer edge of each of a plurality of predetermined portions of one imaging object of the subject in an X-ray image captured based on the detection of X-rays in the detecting step, and determining the identified plurality of predetermined portions; a correction information acquisition step of acquiring position correction information for correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the positional relationship between outer edges;
The position correction information is the relative position of the X-ray irradiation unit with respect to the imaging object of the subject, and the X-ray image in which the outer edges of the plurality of predetermined portions are captured in a predetermined positional relationship. A shooting position correction method including a relative moving direction and moving amount for correcting to a shooting position.

(Item 21)
Of the notification of the position correction information acquired in the correction information acquisition step and the control of changing the position of the X-ray irradiation unit relative to the imaging object of the subject based on the position correction information 21. The photographing position correcting method according to item 20, further comprising a position correcting step of performing at least one.

(Item 22)
The correction information acquisition step includes a correction information acquisition step of calculating the position correction information based on parameter information corresponding to actual distances between the plurality of predetermined portions of the imaging object of the subject. Item 20 or 21, the photographing position correcting method.

Reference Signs List 1, 501 X-ray irradiation unit 1b Display unit 3 Top plate 4 Irradiation unit moving mechanism (moving mechanism)
5 Top plate moving mechanism (moving mechanism)
7 device control unit (movement control unit)
21 X-ray detector 22 X-ray detector 23 Main shot image (image after position correction)
24, 24a, 24b Pre-shot images (images before position correction)
25 appearance image 31 femur 31a medial condyle 31b lateral condyle 36 humerus 39 scapula 81, 681, 881, 981 processing unit (correction information acquiring unit)
82a, 82b Trained model 91, 591 Display unit 100, 500, 600, 800, 900 X-ray imaging apparatus 201 Subject 202 User 811 Imaging unit A, B, C parts

Claims (22)

an X-ray irradiation unit that irradiates X-rays to a subject;
an X-ray detection unit that detects X-rays emitted from the X-ray irradiation unit and transmitted through the subject;
identifying the outer edge of each of a plurality of predetermined portions of one imaging object of the subject in an X-ray image captured based on the detection signal of the X-ray detection unit, a correction information acquisition unit that acquires position correction information for correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the positional relationship between outer edges;
The position correction information is the relative position of the X-ray irradiation unit with respect to the imaging object of the subject, and the X-ray image in which the outer edges of the plurality of predetermined portions are captured in a predetermined positional relationship. An X-ray imaging apparatus including relative movement direction and movement amount for correction to an imageable position. Notification of the position correction information acquired by the correction information acquisition unit, and control for changing the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the position correction information 2. The radiographic apparatus of claim 1, configured to perform at least one of: a movement mechanism for changing the relative position of the X-ray irradiation unit with respect to the subject;
a movement control unit that controls change of the position of the X-ray irradiation unit relative to the subject by the movement mechanism;
The movement control unit controls change of the position of the X-ray irradiation unit relative to the imaging object of the subject by the movement mechanism based on the position correction information acquired by the correction information acquisition unit. 3. The radiographic apparatus of claim 2, configured to perform further comprising a top plate on which the subject is placed;
The movement control unit adjusts the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the position correction information acquired by the correction information acquisition unit. Control for automatically moving the position of at least one of the X-ray irradiator and the top plate so that the positional relationship between the outer edges becomes a position where the X-ray image captured in the predetermined positional relationship can be captured. 4. The X-ray imaging apparatus according to claim 3, wherein further comprising a top plate on which the subject is placed;
When one of the X-ray irradiation unit and the tabletop is moved based on a user's operation, the movement control unit controls the X-ray irradiation unit based on the position correction information acquired by the correction information acquisition unit. 4. The X-ray imaging apparatus according to claim 3, wherein control is performed to restrict movement of one of said top plates. As notification of the position correction information acquired by the correction information acquisition unit, the positional relationship between the outer edges of the plurality of predetermined portions is corrected to a position where the X-ray image captured in the predetermined positional relationship can be captured. 3. A display unit for displaying at least the relative movement direction of the X-ray irradiation unit out of the relative movement direction and the amount of movement of the X-ray irradiation unit with respect to the object to be imaged of the subject. 6. The X-ray imaging apparatus according to any one of 1 to 5. The correction information acquisition unit is configured to obtain the plurality of predetermined portions in the X-ray image based on the positional relationship between the outer edges of the plurality of predetermined portions in the one imaging object of the subject in the X-ray image. The position correction information is configured to acquire a relative positional deviation between the outer edges and acquire the position correction information based on the acquired relative positional deviation between the outer edges of the plurality of predetermined portions. 6. The X-ray imaging apparatus according to any one of 2 to 5. The correction information acquisition unit identifies the outer edge of each of the plurality of predetermined portions of the bone or artificial joint as one of the imaging objects of the subject in the X-ray image, and identifies the identified bone or artificial joint. The position correction information for correcting the relative position of the X-ray irradiation unit with respect to the bone or artificial joint of the subject is acquired based on the positional relationship between the outer edges of the plurality of predetermined portions in The X-ray imaging apparatus according to any one of claims 2 to 5, wherein The correction information acquisition unit is configured to determine the degree of overlap between the outer edges of the plurality of predetermined portions in each of the bones or artificial joints of the subject in the X-ray image. a relative position of the X-ray irradiation unit with respect to the bones or artificial joints of the subject at a position where the X-ray image in which the outer edges of the plurality of predetermined portions overlap with each other can be captured. 9. The X-ray imaging apparatus according to claim 8, configured to calculate said position correction information for correcting . The correction information acquisition unit is capable of capturing the X-ray image in which the outer edges of the plurality of predetermined portions overlap each other when capturing at least one of the knee side of the femur and the scapula of the subject. 10. The radiography according to claim 9, wherein said position correction information for correcting a position of said X-ray irradiation unit relative to said bone or artificial joint of said subject is calculated. Device. The correction information acquiring unit is configured to obtain a relative position between outer edges of the plurality of predetermined portions based on a positional relationship between outer edges of the plurality of predetermined portions in each of the bones or artificial joints of the subject in the X-ray image. a relative position of the X-ray irradiation unit with respect to the bones or artificial joints of the subject at a position where the X-ray image in which the outer edges of the plurality of predetermined portions appear concentrically can be captured. 9. The X-ray imaging apparatus according to claim 8, configured to calculate said position correction information for correcting . The correction information acquiring unit, when imaging the elbow side of the humerus of the subject, places the outer edges of the plurality of predetermined portions of the subject at a position where the X-ray image can be captured concentrically. 12. The X-ray imaging apparatus according to claim 11, configured to calculate said position correction information for correcting a relative position of said X-ray irradiation unit with respect to a bone or an artificial joint. The correction information acquisition unit receives less radiation than when the image after position correction, which is the X-ray image captured after correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject. Based on the positional relationship between the outer edges of the plurality of predetermined portions of the object to be imaged of the subject in the pre-position-corrected image, which is the X-ray image generated based on the irradiation of the amount of X-rays, the position An X-ray imaging apparatus according to any one of claims 1 to 5, configured to acquire correction information. The correction information acquisition unit inputs the X-ray image to a learned model that has been machine-learned using the X-ray image obtained by imaging the imaging object as input data. any one of claims 1 to 5, wherein the outer edges of the plurality of predetermined portions are obtained based on and the position correction information is calculated based on the obtained outer edges of the plurality of predetermined portions. 10. The X-ray imaging apparatus according to claim 1. wherein the correction information acquisition unit is configured to calculate the position correction information based on parameter information corresponding to actual distances between the plurality of predetermined portions of the imaging object of the subject; Item 6. The X-ray imaging apparatus according to any one of items 1 to 5. 16. The X-ray imaging apparatus according to claim 15, wherein said correction information acquisition unit detects, as said parameter information, a size of a detection target portion of said subject in said X-ray image of said subject. 17. The correction information acquisition unit detects, as the parameter information, the size of the detection target portion of the subject from among the X-ray images taken to acquire the position correction information. X-ray imaging apparatus according to. The correction information acquisition unit selects, as the parameter information, the detection target of the subject from among the X-ray images captured in advance at an imaging angle different from that of the X-ray image for acquiring the position correction information. 17. An X-ray imaging device as claimed in claim 16, which detects the size of the part. Further comprising an imaging unit for imaging the appearance of the subject,
The correction information acquisition unit corrects the position based on the parameter information, which is physique information indicating the size of the physique of the subject calculated from the appearance image of the subject acquired by imaging by the imaging unit. 16. An X-ray imaging device according to claim 15, arranged to calculate information. an irradiation step of irradiating the subject with X-rays from the X-ray irradiation unit;
a detection step of detecting X-rays that have passed through the subject;
identifying the outer edge of each of a plurality of predetermined portions of one imaging object of the subject in an X-ray image captured based on the detection of X-rays in the detecting step, and determining the identified plurality of predetermined portions; a correction information acquisition step of acquiring position correction information for correcting the relative position of the X-ray irradiation unit with respect to the imaging object of the subject based on the positional relationship between outer edges;
The position correction information is the relative position of the X-ray irradiation unit with respect to the imaging object of the subject, and the X-ray image in which the outer edges of the plurality of predetermined portions are captured in a predetermined positional relationship. A shooting position correction method including a relative moving direction and moving amount for correcting to a shooting position. Of the notification of the position correction information acquired in the correction information acquisition step and the control of changing the position of the X-ray irradiation unit relative to the imaging object of the subject based on the position correction information 21. The imaging position correcting method according to claim 20, further comprising a position correcting step of performing at least one of them. The correction information acquisition step includes a correction information acquisition step of calculating the position correction information based on parameter information corresponding to actual distances between the plurality of predetermined portions of the imaging object of the subject. 22. The photographing position correcting method according to claim 20 or 21.

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