X-ray imaging apparatus and method for indicating to the user the fluoroscopic imaging capability of the X-ray imaging apparatus.

Abstract

To provide an X-ray imaging apparatus with a relatively simple structure that can reliably ensure that the X-ray tube and the FPD are facing each other. [Solution] The X-ray imaging apparatus comprises an X-ray tube that emits X-rays, an X-ray tube drive mechanism that moves the X-ray tube in three axial directions, an imaging table that houses an X-ray detector and on which the subject is placed, and a processor that controls imaging according to user instructions via an operation panel. The processor acquires position information of the X-ray tube from sensors that detect the movement of the X-ray tube in each of the three axial directions, and displays the relative position of the X-ray tube with respect to the X-ray detector in the form of an indicator on the operation panel or display device.

Description

Technical Field

[0001] The present invention relates to an X-ray imaging apparatus (X-ray fluoroscopic imaging apparatus) capable of performing fluoroscopic imaging, and particularly relates to a technique for improving user-friendliness during fluoroscopic imaging in an X-ray imaging apparatus.

Background Art

[0002] An X-ray imaging apparatus irradiates a subject with X-rays using an X-ray tube, detects the X-rays transmitted through the subject with an FPD (Flat Panel Detector), and acquires an X-ray image. For imaging, there are imaging for obtaining a still image by one X-ray irradiation and fluoroscopic imaging (hereinafter simply referred to as fluoroscopy) for obtaining a moving image (fluoroscopic image) by continuous X-ray irradiation. An apparatus that performs both is called an X-ray fluoroscopic imaging apparatus. In an X-ray fluoroscopic imaging apparatus, according to the standard, when performing fluoroscopy, the X-ray tube and the FPD must always face each other, and it is necessary that the X-rays irradiated from the X-ray tube do not protrude outside the frame of the FPD. The X-ray tube and the FPD are configured to always face each other even when the position of the X-ray tube changes.

[0003] Therefore, a conventional X-ray fluoroscopic imaging apparatus is provided with a mechanism for always facing the X-ray tube and the FPD (for example, Patent Document 1). However, while a conventional X-ray fluoroscopic imaging apparatus can safely acquire a fluoroscopic image by having such a mechanism, the structure of the apparatus itself has become complicated. There is also an X-ray imaging apparatus with a relatively simple structure that does not have a mechanism for always facing the X-ray tube and the FPD (for example, Patent Document 2). However, in order to perform fluoroscopy with such an X-ray imaging apparatus, it is necessary for an inspection technician, a doctor, etc. (hereinafter collectively referred to as an operator) to visually confirm that the X-ray tube and the FPD are facing each other during fluoroscopy, and there is a problem that the time and labor required for the inspection are large.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] The technology described in Patent Document 2 is configured to automatically match the direction of the displayed fluoroscopic image to the orientation of the subject as seen by the operator when determining the irradiation field, thereby improving usability during fluoroscopy. Patent Document 2 also states that the position of the X-ray tube (SID) may be displayed on the control panel.

[0006] However, with this technology, determining the irradiation field of the X-ray tube is done while checking the fluoroscopic image, so the X-ray tube and FPD cannot be aligned until fluoroscopy has begun. Furthermore, if the confirmation is insufficient, it may not be possible to guarantee that the X-ray tube and FPD are always facing each other.

[0007] The present invention aims to provide an X-ray imaging apparatus with a relatively simple structure that can reliably ensure that the X-ray tube and the FPD are facing each other. [Means for solving the problem]

[0008] To solve the above problems, the present invention provides an X-ray imaging apparatus that presents the positional relationship between the X-ray tube and the FPD in a way that is easy for the operator to understand, and that has means to enable the operator to easily operate the apparatus based on that presentation.

[0009] In other words, the X-ray imaging apparatus of the present invention comprises an X-ray tube for irradiating X-rays, a drive mechanism that supports the X-ray tube so as to be movable in three axial directions, and an imaging table that houses an X-ray detector and on which a subject is placed. Furthermore, it comprises a processor that acquires the position of the X-ray tube from the drive mechanism and displays an indicator on a display panel that shows the positional relationship between the X-ray tube and the X-ray detector.

[0010] The present invention also provides a method for indicating to a user that an X-ray imaging apparatus is ready for fluoroscopy. This method is for an X-ray imaging apparatus comprising an X-ray tube for irradiating X-rays, a drive mechanism that supports the X-ray tube so as to be movable in three axial directions, and an imaging table that houses an X-ray detector and on which a subject is placed, and includes displaying an indicator that shows the positional relationship between the X-ray tube and the X-ray detector, updating the display of the indicator when the positional relationship changes due to the relative movement of the X-ray tube with respect to the X-ray detector, and indicating that fluoroscopy is possible when the positional relationship reaches a positional relationship that allows for fluoroscopy.

[0011] In this specification, "display panel" includes both the control panel for operating an X-ray imaging device and the display panel of a display device installed on the control console. Unless otherwise specified by symbols, it is a broad concept that includes both. Furthermore, "imaging table" includes both the bed (also called a bed device) used for imaging when the subject is lying down and the standing imaging table used for imaging when the subject is standing. Furthermore, in this specification, "user" includes all operators of the device (radiographers, doctors, and other operators). [Effects of the Invention]

[0012] According to the present invention, the position of the X-ray tube is displayed in relation to the X-ray detector in conjunction with the movement of the X-ray tube in three axes, so that the operator can confirm in real time that the X-ray tube is in a position (range) facing the X-ray detector. This makes it possible to safely acquire fluoroscopic images even with an X-ray fluoroscopy device with a simple structure.

[0013] In particular, by displaying the positional relationship between the X-ray tube and the X-ray detector in the form of an indicator, the operator can easily confirm the positional relationship between the X-ray tube and the X-ray detector by referring to the indicator, and based on that, can ensure that the two are properly aligned, thus enabling smooth procedures for moving the X-ray tube and starting fluoroscopy. [Brief explanation of the drawing]

[0014] [Figure 1] Figure showing the outline of the X-ray imaging apparatus [Figure 2] Block diagram of the X-ray imaging apparatus [Figure 3] Functional block diagram of the processor (control unit), drive mechanism of the X-ray tube (X-ray tube movement mechanism unit and support device), and display panel [Figure 4] Flowchart showing the operation flow of the X-ray imaging apparatus [Figure 5] Figure explaining the imaging position [Figure 6] Figure showing an example of the display screen of the operation panel in Embodiment 1 [Figure 7] Figure showing the indicator in Embodiment 1 [Figure 8A] Figure showing an example of the positional relationship where the imaging part and the X-ray tube are not facing each other [Figure 8B] Figure showing an example of the positional relationship where the imaging part and the X-ray tube are facing each other [Figure 9] Figure showing the change of the indicator in Embodiment 2 [Figure 10] Flowchart showing the control flow in Embodiment 3 [Figure 11] Flowchart showing the control flow in Embodiment 3 [Figure 12] Figure explaining the display example in Embodiment 4

Embodiments for Carrying Out the Invention

[0015] Hereinafter, embodiments of the X-ray imaging apparatus of the present invention will be described. First, the outline of the X-ray imaging apparatus to which the present invention is applied will be described with reference to FIGS. 1 and 2. As shown in Figure 1, the X-ray imaging apparatus 1 comprises an X-ray tube 12 connected to a high-voltage generating unit 15 (Figure 2), an X-ray irradiation unit 10 on which the X-ray tube 12 is mounted, an X-ray tube moving mechanism 50 for moving the X-ray tube 12 in three axial directions and rotational directions, and an imaging table. The imaging table includes a patient bed device 20 equipped with a top plate 21 on which the subject lies, and each is provided with a storage compartment for an X-ray detector, usually an FPD, which detects X-rays irradiated from the X-ray tube and transmitted through the subject. In the following description, the X-ray detector will be referred to as FPD 40.

[0016] The X-ray imaging apparatus 1 is also equipped with an operating unit 60 and an operating console 80 for the operator to control the X-ray irradiation unit 10 and the X-ray tube moving mechanism 50. The operating unit 60 is attached to the X-ray irradiation unit 10 and can be moved independently of the X-ray tube 12, etc. The operating console 80 is installed in an operating room that is shielded from the imaging room where the X-ray irradiation unit 10, etc., is located.

[0017] Furthermore, the X-ray imaging apparatus 1 is connected to a processor 70 that controls the high-voltage generation unit 15 described above to control imaging, and also performs necessary processing for image generation using the transmitted X-ray information detected by the FPD 40. The processor 70 may be housed in the control console 80, or it may be installed in a location separate from the X-ray imaging apparatus 1.

[0018] The configuration of the X-ray irradiation unit 10 is similar to that of a typical X-ray irradiation unit, and as shown in Figure 2, it includes an X-ray tube 12 for irradiating the subject with X-rays, an X-ray diaphragm 13 for setting the X-ray irradiation area for the subject, an irradiation lamp 14 for confirming the area irradiated by the X-ray diaphragm 13 in visible light, and a support 11 for supporting the X-ray tube 12 and the X-ray diaphragm 13, etc. The support 11, together with the X-ray moving mechanism 50 described later, constitutes the drive mechanism for the X-ray tube.

[0019] The X-ray tube moving mechanism 50 includes a horizontal moving mechanism (X-axis drive mechanism and Y-axis drive mechanism) such as a rail 55, a vertical moving mechanism (Z-axis drive mechanism) not shown, and a rotation mechanism, with part or all of the vertical moving mechanism and the rotation mechanism being incorporated into the X-ray irradiation unit 10. The X-ray tube moving mechanism 50 equipped with such a mechanism can freely move and support the X-ray tube 12 in the longitudinal direction of the top plate 21 which is the axis direction of the subject placed on the top plate 21 (hereinafter referred to as the X-axis direction), the short direction of the top plate 21 which is perpendicular to the X-axis direction (hereinafter referred to as the Y-axis direction), and in a direction perpendicular to the surface of the top plate 21 on which the subject 100 is placed, which is perpendicular to the X and Y axes (hereinafter referred to as the Z-axis direction). Furthermore, it is possible to rotate the X-ray tube 12 around the Y-axis, for example, to rotate the irradiation direction of the X-rays irradiated from the X-ray tube 12 by any angle (for example, within a range of ±180 degrees) between the vertical and horizontal directions. As shown in Figure 3, the X-axis drive mechanism, Y-axis drive mechanism, Z-axis drive mechanism, and rotation mechanism are equipped with a locking mechanism (e.g., an electromagnetic lock) such as an electromagnetic brake to fix / release the position of the X-ray tube, etc., at a predetermined position.

[0020] The X-ray tube moving mechanism 50 is also equipped with sensors 51 (X-axis sensor, Y-axis sensor, Z-axis sensor, and rotation sensor) that detect movement (amount of movement) in each direction. As sensors 51, known sensors such as mechanical sensors like encoders, acceleration sensors, optical or magnetic sensors, etc., can be used. The outputs of these sensors 51 are sent to the processor 70.

[0021] Although the rail 55 of the X-ray tube moving mechanism 50 is fixed to the ceiling of the imaging room, the patient bed device 20 may be configured to be movable relative to the rail 55. In that case, the movement of the patient bed device 20 (which houses the FPD 40) can be configured by sending the output of a sensor 21 that detects the amount of movement to the processor 70.

[0022] As shown in Figure 1, the operation unit 60 is equipped with an operation handle 61, which allows the operator to move and rotate the X-ray tube moving mechanism 50 of the X-ray irradiation unit 10 along each axis. In addition to the operation handle 61, the operation unit 60 is equipped with an operation panel 62 for the operator to input information necessary for imaging and for this information to be displayed to the operator. The control console 80, like the operation unit 60, is equipped with various buttons (not shown) necessary for imaging, a GUI, and a display device (display panel 82) for displaying the acquired X-ray images. Switching between imaging and fluoroscopy is performed by operating a switch button provided on the control panel 62 and / or the control console 80 (display panel 82). For example, when the fluoroscopy button is pressed, the display content also switches to fluoroscopy mode. The display content will be described in detail in the embodiments described later.

[0023] The processor 70 performs the calculations and processing necessary for controlling the X-ray imaging device and generating images. In Figure 2, the functions of the processor 70 are shown divided into two blocks 70A and 70B, one related to control and the other to image generation. However, in the following explanation, it will be referred to collectively as the processor 70. The part of the processor 70 that implements the functions related to control (functions of block 70A) will also be called the control unit 75.

[0024] The functions of the processor 70, including image generation processing, are similar to those of a typical X-ray imaging device. These include an image processing unit 71 that processes transmitted X-rays detected by the FPD 40 to generate an X-ray image, an image storage unit 72 that stores the generated or processed image, and an image display unit 73 that generates a display image. Detailed descriptions of these functional units are omitted in this specification.

[0025] The control unit 75 controls various operations performed by the X-ray imaging apparatus 1, such as the imaging operation of the X-ray irradiation unit, the operation of the X-ray tube movement mechanism 50, and the control of the display. The X-ray imaging apparatus 1 of this embodiment is characterized by a display control function that displays the positional relationship between the X-ray tube and the FPD in real time on the operation panel or the like, in conjunction with the operator's operation of the X-ray tube movement mechanism 50. The specific display will be described in detail in the embodiments described later.

[0026] The configuration of the processor 70 is not particularly limited, but can be composed of one or more hardware components or a combination of hardware and a program. The type of hardware is not limited; for example, the processor may be composed of a CPU (Central Processing Unit), an MPU (Micro Processing Unit), a programmable logic device such as an FPGA (Field Programmable Gate Array), a dedicated circuit for executing a specific process such as an ASIC (Application Specific Integrated Circuit), a GPU (Graphic Processing Unit), or an NPU (Neural Processing Unit). Furthermore, the type of hardware may be a combination of different types of hardware. When multiple hardware components are configured to execute one or more processes of a given processor, these multiple hardware components may reside in physically separate devices or in the same device.

[0027] When the processor 70 is implemented as a combination of hardware and a program, the program may be firmware or software such as microcode. Alternatively, the program may be, for example, a group of program modules, and each of its functions may be implemented by a processor configured to perform its respective function. The program may also be program code or multiple code segments stored in one or more non-temporary computer-readable media (e.g., storage media or other storage).

[0028] The operation of the X-ray apparatus configured as described above will now be explained. Figure 4 shows the processing flow. Here, the displays on the operation panel 62 and the display panel 82 of the control console 80 will be collectively referred to as the display unit.

[0029] When an examination is started, the display on the display unit switches according to the type of examination specified by the operator via the control unit 60 or control console 80, namely, whether it is a radiographic examination (radiography mode) or a fluoroscopic examination (fluoroscopy mode) (S1). For example, the display unit initially displays radiographic mode, but if a fluoroscopic examination is selected, it displays fluoroscopic mode (S2). In fluoroscopy mode, in addition to displaying subject information and imaging conditions, an indicator showing the position of the X-ray tube is displayed. Details of the indicator will be explained in the embodiment described later, but it includes indicator axes corresponding to each axis on which the X-ray tube can move and a pointer that shows the current position of the X-ray tube, and the position of the X-ray tube can be visually grasped by moving the position of the pointer relative to the indicator axis.

[0030] After the operator confirms the imaging conditions in fluoroscopy mode, such as tube voltage, tube current, imaging distance (SID), and the range of the irradiation field, and confirms that the FPD is set (S3), the operator operates the control unit 60 to drive the X-ray tube moving mechanism 50 and positions the X-ray irradiation unit 10 to a position (target position) that satisfies the set imaging distance and faces the set FPD 40 (S4). In conjunction with this operation by the operator, the current position of the X-ray irradiation unit 10 is displayed on the display panel indicator as a change in the relative position of the pointer. This allows the operator to confirm that the X-ray irradiation unit 10, i.e., the X-ray tube 12, has been positioned at the target position while operating using the control unit 60 (S5).

[0031] Once the X-ray tube 12 is positioned at the target location, the operator presses the fluoroscopy start button to begin imaging in fluoroscopy mode (S6). If fluoroscopy mode is not selected, imaging will be performed in normal imaging mode (S7).

[0032] According to this embodiment, the movement of the X-ray irradiation unit 10 by the operator is displayed as an indicator on the display panel (particularly the operation panel 62), so that the positional relationship between the X-ray tube and the X-ray detector (FPD), which is the result of the operation, can be confirmed while operating the X-ray tube. This allows the X-ray tube to be set to the target position reliably and quickly, and the effort and time required for imaging can be greatly reduced. Furthermore, according to this embodiment, since the indicator is composed of indicator axes corresponding to each axis of the X-ray tube movement mechanism, the axial direction to be moved can be easily grasped from the indicator display.

[0033] The following describes specific embodiments of the display of the X-ray imaging apparatus of the present invention.

[0034] <Embodiment 1> In this embodiment, an example of the display on the operation panel 62 when operating the X-ray irradiation unit 10 will be described, using the case of fluoroscopy in the supine position shown in Figure 5 as an example. First, the indicators displayed on the operation panel 62 will be described with reference to Figures 6 and 7.

[0035] Figure 6 shows an example of a display screen shown on the control panel 62 during fluoroscopic imaging. As shown in the figure, the display screen 600 is broadly divided into an imaging condition display area 610 where the operator sets imaging conditions and displays the operation details, and an X-ray tube position display area 620 which shows the positional relationship of the X-ray tube 12 with respect to the FPD 40. The imaging condition display area 610 includes an area that shows imaging conditions such as the angle of the X-ray tube 12, SID, and aperture range (irradiation field range), as well as a GUI area with buttons for setting these conditions. In addition to these areas, there may also be an area for displaying subject information, and an area for displaying icons that show the storage status of the FPD and the aperture opening. The X-ray tube position display area 620 includes an indicator 630 that shows the position of the X-ray tube in conjunction with the operator moving the X-ray irradiation unit. Separately from the indicator 630, there may be an area that shows position information numerically (for example, the part adjacent to the indicator 630).

[0036] As shown in Figure 7, the indicator 630 includes an indicator shaft 631 and a pointer 633. The indicator shaft 631 consists of three indicator axes corresponding to the movement direction (X-axis and Y-axis) of the rail 55 of the X-ray tube moving mechanism 50 and the vertical movement direction (Z-axis) of the support 11. The pointer 633 moves along each indicator axis and points to the position on each indicator axis corresponding to the position of the X-ray tube in the three axial directions.

[0037] Each indicator axis 631 in the axial direction is colored with a different color, such as yellow, red, or blue, and the brightness of the color changes from the center to the ends along the longitudinal direction of the indicator axis 631. For example, the central part of the indicator 631 is the brightest color (e.g., white), the ends are the darkest color, and the intermediate parts (hatched areas in the figure) are lighter in color. The central part is the acceptable range centered on the target X-ray tube position (the position where X-rays are irradiated to the center of the FPD), and is a narrower range than the other areas. The indicator axis in the Z-axis direction may display a set SID (numerical value).

[0038] In this way, visibility can be improved by making the color brighter towards the center of the indicator axis. In particular, if the background of indicator 630 is a dark color such as black, visibility will be improved by making the center white.

[0039] In Figure 7, pointer 633 is represented as a triangle, but the shape of the figure is not limited to any shape that indicates the position; it can be a dot, an arrow, an inverted triangle, or any other shape.

[0040] The display area of ​​the indicator 630 may, although not required, include a button (release button 640) for releasing the electromagnetic brake that locks the movement of the X-ray tube, which is provided in the X-ray tube movement mechanism 50. Three release buttons 640 are provided, corresponding to each axis, and each is colored the same as the indicator axis 631 of that axis, making it easy to see at a glance which axis's lock needs to be released. In the illustrated example, release buttons 640 are provided on both the left and right sides of the area that displays the indicator axis 631, allowing operation from both the right and left hands.

[0041] The following describes the processing flow of the processor 70 in this embodiment. Here, as an example, the display control will be described using the case where the operation panel 62 of the operation unit 60 is targeted.

[0042] When fluoroscopy mode is selected via the control console 80 or control panel 62, the processor 70 adds the aforementioned indicator 630 to the display screens of the control console 80 and control panel 62 to display the transmission mode. Next, the processor 70 acquires position information of the X-ray tube 12 from each sensor 51 of the X-ray movement mechanism 50 and reflects this position information in the pointer 633 of the indicator 630 on the control panel 62. That is, the current position of the X-ray tube, i.e., the position where the X-rays emitted from the X-ray tube (center of the irradiation field) are directed toward the FPD, is displayed as the position of the pointer 633 on the indicator axis 631. In the example shown in Figure 7, the X-ray tube is positioned to satisfy the set SID (120 cm) in the Z-axis direction, but movement is required in the X-axis and Y-axis directions to position it opposite the FPD.

[0043] When the X-ray tube 12 is moved toward the target position, the processor 70 receives position information from the sensor 51 of the X-ray movement mechanism 50 and moves the pointer 633 along the indicator axis 631. Even if the X-ray tube 12 is not moving, if the patient table 20 (which houses the FPD 40) moves, the positional relationship between the X-ray tube 12 and the center of the FPD changes. In this case, the processor 70 receives position information from the sensor 21 (Figure 3) that detects the movement of the patient table 20 and moves the pointer 633 displayed on the operation panel 62. By following the movement of the patient table 20 in this way, it is possible to display the positional relationship between the X-ray tube and the FPD within the limited display area. Alternatively, instead of moving the pointer 633, the indicator axis 631 may be moved. Moving the indicator axis 631 makes it easier for the operator to intuitively understand that the relative position to the patient table 20 has changed.

[0044] As a result of the operations described above, when the X-ray tube 12 and FPD 40 are positioned opposite each other, as shown in Figure 8B, the processor 70 (display control) displays an indication on the operation panel 62 that irradiation is possible. Upon confirming this indication, the operator can press the irradiation button to start imaging. During X-ray irradiation, an indication that irradiation is in progress is also displayed.

[0045] The indication of whether irradiation is possible or in progress can be conveyed by messages such as "Irradiation possible" or "Irradiation in progress," or by the illumination of a lamp. However, in the example shown in Figure 7, the operator is shown whether irradiation is possible or in progress by changing the color of the frame 650 surrounding the window displaying the indicator 630. The color is not particularly limited, but a color that intuitively prompts action or a color that issues a warning can be used. For example, the frame color could be gray while the X-ray tube is moving, change to green when irradiation is possible, and change to yellow when irradiation begins.

[0046] As a result, with the FPD placed in a predetermined fluoroscopic position (approximately the center of the bed), when an adjacent pointer 633 reaches the center of the white area on all three indicator axes 631, the window frame 650 displaying the indicator 630 changes from gray to green, indicating that fluoroscopy is possible. Subsequently, when fluoroscopy begins, the processor 70 changes the color of the window frame 650 from green to, for example, yellow, to indicate that X-ray irradiation is in progress.

[0047] According to this embodiment, the X-ray tube and the FPD are positioned opposite each other easily and reliably because the positional relationship between the X-ray tube and the FPD changes in conjunction with the movement of the X-ray tube by operating the X-ray tube moving mechanism and / or the movement of the flat panel display (FPD) relative to the X-ray tube moving mechanism, and this is indicated by indicators corresponding to the direction of movement of each axis of the X-ray tube. In particular, the operator can intuitively grasp the direction and amount of movement along the axial direction via the indicators, which greatly improves the efficiency of operation.

[0048] Furthermore, according to this embodiment, by providing an indicator to show whether irradiation is possible or in progress, it is possible to guide the operator to perform reliable and safe operations.

[0049] <Application example of Embodiment 1> In addition to the indicator display of Embodiment 1, markers indicating the movable axis direction may be added to the movable elements of the X-ray imaging apparatus 1. For example, as shown in Figures 8A and 8B above, markers 51 colored to correspond to the color of the indicator axis are provided on the longitudinal and transverse ends of the rail 55 of the X-ray moving mechanism 50 and on the extendable support portion 11, respectively. For example, the marker in the X-axis direction (longitudinal direction) is yellow, the marker in the Y-axis direction (transverse direction) is red, and the marker in the Z-axis direction is blue. In the figures, the markers are attached to a part of the side along each axis direction, but the length and position of the markers 51 are not particularly limited as long as they can be seen at a glance by the operator. To ensure that they can be seen at a glance, if it is a rail, it is preferable that the markers are in a position that can be seen when the operator looks up from below.

[0050] By providing corresponding markers on the drive unit side of the device in addition to the indicator display, the ease of operation can be further improved.

[0051] <Embodiment 2> In Embodiment 1, the case of fluoroscopy in a supine position was described as an example, but a feature of this embodiment is that the display on the display panel (operation panel 62 or display device on the control console) is changed according to the imaging position.

[0052] As shown in Figure 5, imaging can be performed in a supine position with the subject 100 lying on the tabletop 21, or in an upright position with the subject 100 standing on the upright imaging table (also called a Bucky table) 30. The X-ray tube 12 is configured to be able to rotate ±90 degrees from a vertically downward position. In fluoroscopy, switching between supine and upright positions can be done by providing a switch button on either the control panel 62 or the control console 80, or both, to switch positions by pressing the switch button, or by rotating the X-ray tube 90° to enter upright mode.

[0053] Furthermore, during standing imaging, the X-ray tube 12 is rotated 90 degrees from a vertically downward position, and the FPD 40 is set on the standing imaging table 30 for imaging. This rotational movement of the X-ray tube 12 is detected by a rotation sensor (Figure 2), and the detection signal is sent to the processor 70.

[0054] When the operator rotates the X-ray tube 12, the control panel 62 attached to the X-ray irradiation unit 10 also rotates simultaneously, for example, rotating 90 degrees from the state shown in the upper part of Figure 5 to the state shown in the lower part. When the processor 70 (display control) receives a rotation detection signal of the X-ray tube 12 from the rotation sensor, it changes the display of the indicator 630 on the rotated control panel 62 from vertical to horizontal. That is, as shown in Figure 9, the indicator axis 631(X) in the X-axis direction, which was parallel to the longitudinal direction of the frame 650 of the indicator 630 window, and the indicator axis 631(Z) in the Z-axis direction, which was parallel to the short direction, are changed in vertical display to have the indicator axis 631(X) parallel to the short direction of the frame 650 and the indicator axis 631(Z) parallel to the longitudinal direction of the frame 650, respectively. Note that the display switching can also be done by pre-setting the angle (tube angle) of the X-ray tube 12 to be switched, and switching between vertical and horizontal display at the switching angle. For example, the vertical downward tube angle could be set to 0°, and when moving from vertical downward to 90°, the display could be set to vertical when the tube angle is 60° or greater. Conversely, when moving from the 90° position (horizontal) to vertical downward, the display could be set to horizontal when the tube angle is 30° or less.

[0055] This ensures that the correspondence between the three axes of the device and the indicator axis is maintained even when the control panel 62 rotates. In this state, the X-ray irradiation unit 10 is operated to a position where it faces the FPD 40, and fluoroscopy is started after confirming that it has reached the facing position, as in Embodiment 1. Also in this embodiment, as in Embodiment 1, when the target position is reached, the irradiation ready state or irradiation in progress state is indicated, for example, by changing the color of the frame 650.

[0056] According to this embodiment, in addition to the effects of Embodiment 1, by changing the display on the indicator axis according to the change in the imaging position, the X-ray tube 12 and the FPD 40 can be conveniently positioned opposite each other not only in supine position but also in standing position imaging.

[0057] <Embodiment 3> This embodiment is characterized by the electromagnetic locks provided on each axis of the X-ray movement mechanism 50 and the buttons that operate them (Figure 6: release button 640). The configuration and functions of the other indicators are the same as in Embodiments 1 and 2, and redundant explanations are omitted.

[0058] As described in Embodiment 1, the release button 640 is a button or button-shaped GUI that is colored in the same color as the corresponding axis direction. When the release button 640 is not pressed, the electromagnetic lock is locked. When the release button 640 is pressed, the lock is released, and the X-ray tube 12 can move in the axis direction in which the lock was released. The electromagnetic lock is also locked when the X-ray tube reaches the target position facing the FPD and the target position in the Z direction that satisfies the SID.

[0059] Locking at the target position can be achieved, for example, by utilizing a function called PBS (Programmable Brake System) for the rails 55 (X-axis and Y-axis) of the X-ray movement mechanism 50. Specifically, by setting the PBS point to the transmissible position, i.e., the X / Y coordinates of the center of the FPD, the brake lock is applied to the X-axis and Y-axis at the PBS point. In other words, the brake lock is applied when the pointer 633 is at the center of the X-axis and Y-axis indicator axes 631 on the operation panel 62.

[0060] For the Z-axis, for example, a motor with an auto-tracking function can be used in the vertical movement mechanism responsible for movement in the Z-axis direction. With the auto-tracking function, once imaging conditions such as SID are set, the X-ray tube 12 is automatically moved to a fluoroscopic Z-axis position (target position). At that time, in the display of the indicator 630, the pointer 633 is at the center of the indicator axis 631 in the Z-axis direction. Note that when movement in the Z-axis direction is performed manually, the electromagnetic lock will not engage even if the pointer 633 is at the center of the indicator axis 631 in the Z-axis direction. However, the system may be configured to provide feedback that the pointer 633 has reached the center of the indicator axis 631 and lock the electromagnetic lock in the Z-axis direction.

[0061] In the configuration described above, when an operator operates the X-ray tube 12, they press the release button 640 for the axis direction (e.g., the Y-axis direction) to release the electromagnetic lock on that axis. At this time, to indicate that the lock has been released, the color of the pointer 633 for the unlocked axis may be changed. For example, it may be red when locked and white after the lock has been released. Alternatively, a pilot lamp (LED) (not shown) may be attached to the electromagnetic lock release button 640, which may be turned off (lock released) or turned on (locked).

[0062] As a result of the movement, when the X-ray tube 12 reaches the PBS point (target position), the electromagnetic lock automatically engages, preventing further movement. This operation is performed for other axes (for example, the X-axis direction) to position the X-ray tube 12 so that it is directly facing the FPD 40. For the Z-axis direction, when moving the X-ray tube 12 to the target position using the auto-tracking described above, the electromagnetic lock (brake) is released internally by motor control and the X-ray tube 12 moves automatically without having to press the Z-axis lock release button. However, instead of movement controlled by motors using auto-tracking, it is also possible to manually move the X-ray tube 12 in the Z direction by pressing the Z-axis lock release button, similar to the X-axis and Y-axis.

[0063] The processing flow of the processor 70 in this embodiment is shown in Figures 10 and 11. In this example, the imaging table (bed device 20) is set in a predetermined position and remains stationary, and auto-tracking is used for the Z-axis. Display control will be explained using the operation panel 62 of the operation unit 60 as an example.

[0064] First, as shown in Figure 10, when the fluoroscopy mode is selected via the control console 80 or the control panel 62 (S11), the processor 70 adds the indicator 630 described above to the display screens of the control console 80 and the control panel 62. If the fluoroscopy mode is not selected and the indicator is displayed on the display screen, the display is removed and the system switches to imaging mode. When the fluoroscopy mode is selected, the processor 70 acquires position information of the X-ray tube 12 from each sensor 51 of the X-ray movement mechanism 50 and reflects this position information in the pointer 633 of the indicator 630 on the control panel 62 (S12). That is, the current position of the X-ray tube, i.e., the position where the X-rays emitted from the X-ray tube (center of the irradiation field) are directed toward the FPD, is displayed as the position of the pointer 633 on the indicator axis 631.

[0065] Next, when the operator presses one or more of the Y-axis or X-axis unlock buttons 640 (S13), the X-ray tube 12 can be moved via the X-ray movement mechanism 50 of the pressed axis, and when the X-ray tube 12 is moved toward the target position, the pointer 633 moves along the indicator axis 631 (S14). If no unlock button is pressed, the electromagnetic lock remains locked (S16). For the Z-axis, when motor control of the Z-axis drive mechanism is started (S13-1), the electromagnetic lock of the Z-axis is released and movement starts automatically (S14-1 to S14-3). The locked and unlocked (movable) states for the three axes are independent of each other, and it is possible to move other axes while one or more are locked, or to move all of them while they are unlocked.

[0066] For example, when the unlock button for the X-axis drive mechanism is pressed (S13), movement in the X-axis direction becomes possible (S14). As a result of the movement in the X-axis direction, when the X-ray tube position enters the PBS point of the X-axis (S15), it automatically enters an electromagnetic lock state (S16). At this time, the pointer 633 is in the irradiation range. The same applies to the Y-axis; as a result of the movement, when it enters the PBS point of the Y-axis (S15), it automatically enters an electromagnetic lock state (S16). For the Z-axis, as described above, the auto-tracking function is started by motor control (S14-1), and the X-ray tube 12 is moved to the target position (S14-2). The pointer 633 moves in conjunction with this movement, and when auto-tracking is completed, the pointer 633 is in the irradiation range (S14-3). The electromagnetic lock of the Z-axis also enters the locked state (S16).

[0067] Next, as shown in Figure 11, the processor 70 confirms that the X, Y, and Z axes are within the irradiation range and that the FPD is set in the predetermined position (S17, S18). Then, it confirms that the FPD 40 and the X-ray tube 12 are facing each other, that is, the X-ray tube angle is 0 degrees in the supine position and +90 degrees or -90 degrees in the standing position (S19), and that the opening of the X-ray diaphragm is set to a range in which X-rays are not irradiated outside the image-receiving surface of the FPD to be irradiated, and that the X-ray diaphragm is inserted in front of or inside the entire image-receiving surface of the FPD (S20). The processor then puts the X-ray tube 12 into an irradiation standby state and displays "Irradiation ready" on the operation panel 62 (S21). The display of "Irradiation ready" can also be done with text information, but in this embodiment, the color of the indicator frame 650 is changed from gray to green, for example. The judgments in S17 to S20 can be performed in parallel. If even one judgment is N, the display on the control panel will not show a state where illumination is possible. For example, the color of the indicator frame 650 will remain in its initial state (e.g., gray).

[0068] When the irradiation-ready status is displayed and the operator presses the irradiation button (S22), X-ray irradiation is performed, and during that time, the display shows "Irradiation in progress". For example, the color of the frame of indicator frame 650 is changed to yellow (S23). The processor 70 continues to check the conditions in S17 to S20 described above even after the operator presses the irradiation button (S24). If even one of the conditions becomes N, even if fluoroscopic X-rays are being irradiated, the X-ray irradiation is forcibly stopped (S27), and the system transitions to state S28 (the color of the control panel frame is gray).

[0069] If fluoroscopy is completed (S25), the display is returned to the default display and the process ends (S26). If fluoroscopy is to be repeated under the same conditions, the process returns to S22. Although not shown in the diagram, if fluoroscopy is to be performed with a different imaging position, the process returns to S12 in Figure 8 and the X-ray tube 12 is moved.

[0070] According to this embodiment, a button (release button 640) for switching the locked state of the electromagnetic locks provided in the axial mechanisms of the X-ray tube movement mechanism is provided on the operating unit 60, and the release button 640 is provided with a visually identifiable display of the locked state and the unlocked state, thereby enabling the operator to move the X-ray tube 12 in a sequential manner. Furthermore, by controlling the movement of the X-ray tube 12 in association with the locked state, it is possible to reduce the effort and time required for operation that depends on the operator's skill, such as overshooting the target position during the movement of the X-ray tube 12, or taking a long time to reach the target position because fine adjustments are not made properly when just before the target position.

[0071] The functions and displays of the electromagnetic lock release button described in Embodiment 3 can also be applied to other embodiments, and such embodiments are also included in the present invention.

[0072] <Embodiment 4> In the embodiments described above, it was assumed that the FPD 40 was properly set in the storage compartment of the patient device 20 or the standing imaging table 30. However, there are cases where the FPD 40 is not set or has been moved from its set position. For example, depending on the patient device 20, there may be multiple storage compartments for the FPD or a mechanism that allows it to slide within the storage compartment. If the FPD position changes after the imaging conditions have been set, the target of the X-ray tube 12 set based on the imaging conditions may be different, or imaging may not be possible at all. This embodiment relates to the display panel display in cases where the FPD is not in the set position.

[0073] As a prerequisite, the X-ray imaging apparatus 1 is equipped with a sensor such as a photosensor (Figure 3) in the FPD housing, which detects whether or not the FPD is in a set position and sends the result to the processor 70. The processor 70 (display control) assumes that it has received a detection signal from the sensor indicating that the FPD is in a set position, and displays the information on the display panel according to the embodiments 1 to 3 described above.

[0074] If there is no detection signal from the sensor when the X-ray tube 12 reaches the target position, the processor 70 changes the color of the frame 650 (green in the above example, indicating that irradiation is possible) from green to, for example, the color when the target position has not been reached, such as gray, as shown in S28 of Figure 11 and Figure 12. From this change in color, the operator can recognize that the X-ray tube has reached the target position but is not in an irradiation-ready state, that is, the FPD is not in the correct position, and thus can prevent accidents such as starting imaging even though the FPD has not moved from its set position because it is not in an irradiation-ready state.

[0075] In addition to changing the color of the frame 650 of indicator 630, or instead, it is also possible to display a message such as "FPD is not set correctly" or to illuminate a warning light.

[0076] According to this embodiment, by adding a warning display in case the FPD is not properly installed, the essential condition for fluoroscopy, which is the opposing arrangement of the X-ray tube and the FPD, can be reliably ensured.

[0077] Although embodiments of the X-ray imaging apparatus of the present invention have been described above, the present invention is not limited to these embodiments. Known configurations can be added, and configurations not essential for carrying out the invention can be omitted. Such modifications are also included in the present invention. Furthermore, the above-described embodiments can be combined as appropriate, as long as they do not contradict each other technically, and such combinations are also included in the embodiments of the present invention. [Explanation of Symbols]

[0078] 1: X-ray imaging device, 10: X-ray irradiation unit, 11: Support (drive mechanism), 12: X-ray tube, 20: Patient table device, 21: Tabletop, 30: Standing imaging table, 40: FPD (X-ray detector), 50: X-ray moving mechanism (drive mechanism), 55: Rail, 60: Control unit, 63: Control panel, 70: Processor, 75: Control unit, 80: Control console, 82: Display panel, 600: Display screen, 630: Indicator, 631: Indicator axis, 633: Pointer, 640: Release button, 650: Frame

Claims

1. The system comprises an X-ray tube for irradiating X-rays, a drive mechanism that supports the X-ray tube so that it can move in three axial directions, and an imaging table that houses an X-ray detector and on which the subject is placed. An X-ray imaging apparatus characterized by comprising a processor that acquires the position of the X-ray tube from the drive mechanism and displays an indicator on a display panel that represents the positional relationship between the X-ray tube and the X-ray detector.

2. An X-ray imaging apparatus according to claim 1, The indicator displayed on the display panel includes three indicator axes corresponding to the three axes in which the X-ray tube can move, and a pointer indicating the position of the X-ray tube on the three indicator axes. The X-ray imaging apparatus is characterized in that the processor changes the position of the pointer in accordance with the movement of the X-ray tube.

3. An X-ray imaging apparatus according to claim 2, The X-ray imaging apparatus is characterized in that the processor displays each of the three indicator axes in a different color.

4. An X-ray imaging apparatus according to claim 2, The drive mechanism includes an X-ray rotation mechanism that changes the direction of the X-rays irradiated from the X-ray tube between the vertical and horizontal directions. An X-ray imaging apparatus characterized by changing the display of an indicator on the display panel according to the angle of the X-ray tube.

5. An X-ray imaging apparatus according to claim 2, The aforementioned imaging table includes a bed for photographing the subject in a supine position and an imaging table for photographing the subject in a standing position. The X-ray imaging apparatus is characterized in that the processor arranges the indicator axes displayed on the display panel differently depending on whether the imaging is performed in a supine position or an upright position.

6. An X-ray imaging apparatus according to claim 2, The X-ray imaging apparatus is characterized in that the drive mechanism includes markers that enable identification of the three axial directions corresponding to each of the three axial indicator axes displayed on the display panel.

7. An X-ray imaging apparatus according to claim 1, The display on the display panel includes a display that makes it possible to identify whether the X-ray tube and the X-ray detector are in a positional relationship that allows imaging in fluoroscopy mode and / or a positional relationship that does not allow imaging. The X-ray imaging apparatus is characterized in that the processor displays in a way that allows identification that the positional relationship is such that imaging is possible in the fluoroscopy mode when the position of the X-ray tube is at a preset position in all three axes.

8. An X-ray imaging apparatus according to claim 1, The X-ray imaging apparatus is characterized in that the display on the display panel includes an indication that the X-ray detector is stored in a predetermined position on the imaging table or is not stored in a predetermined position.

9. An X-ray imaging apparatus according to claim 1, The X-ray imaging apparatus is characterized in that the processor controls switching between an imaging mode in which imaging is performed with a single X-ray irradiation from the X-ray tube and a fluoroscopy mode in which fluoroscopic imaging is performed with a time-series of X-ray irradiations, and in the fluoroscopy mode, the indicator is displayed on the display panel.

10. An X-ray imaging apparatus according to claim 1, The drive mechanism includes a locking mechanism that restricts the movement of the X-ray tube in one or three axes. The display panel includes a release button (GUI) that accepts instructions to release the locking mechanism. The X-ray imaging apparatus is characterized in that the processor releases the locking mechanism for the axis in which the release button has been pressed and the locking mechanism has been released, and adds a display on the display panel indicating that the locking mechanism has been released.

11. A method for indicating to a user that a fluoroscopic imaging device is ready, comprising an X-ray tube for irradiating X-rays, a drive mechanism for supporting the X-ray tube so as to be movable in three axial directions, and an imaging table for housing an X-ray detector and on which a subject is placed. An indicator showing the positional relationship between the X-ray tube and the X-ray detector is displayed. As the relative position of the X-ray tube moves with respect to the X-ray detector, the indicator display is updated when the positional relationship changes. A method that includes indicating that fluoroscopic imaging is possible when the aforementioned positional relationship reaches a positional relationship that allows for fluoroscopic imaging.

12. The method according to claim 11, The movement of the X-ray tube further includes rotation of the X-ray tube, which is accompanied by a change in the direction of X-ray irradiation. A method characterized by changing the orientation of the indicator display in accordance with the change in the X-ray irradiation direction.

13. The system comprises an X-ray tube for irradiating X-rays, a drive mechanism for moving the X-ray tube in three axial directions, a shooting table for housing an X-ray detector and for placing the subject, and a processor that controls the shooting according to instructions from the operator via a control panel. The X-ray imaging apparatus is characterized in that the processor acquires positional information of the X-ray tube from sensors that detect the movement of the X-ray tube in each of the three axes, and displays an indicator on the operation panel or display device that represents the relative position of the X-ray tube with respect to the X-ray detector.

Images