X-ray diagnostic apparatus and control method thereof

Abstract

To provide an X-ray diagnostic apparatus capable of achieving a new X-ray diaphragm even when setting a setting visual field region of a small visual field size at an arbitrary position in an effective visual field region.SOLUTION: An X-ray diagnostic apparatus includes: an X-ray generator for generating an X-ray, which includes an X-ray diaphragm for restricting the X-ray; an X-ray detector for detecting the X-ray generated by the X-ray generator and passing through a subject; a visual field region setting unit for setting a setting visual field region of a visual field size smaller than an effective visual field region in the effective visual field region of the X-ray detector; a reference point determination unit for determining a reference point for the restriction in the setting visual field region; and an X-ray diaphragm adjusting unit for adjusting the restriction of the X-ray around the reference point in the setting visual field region that has been set on the basis of operation of an operation unit.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The embodiments disclosed in this specification and the drawings relate to an X-ray diagnostic device. [Background technology]

[0002] An X-ray diagnostic device is a device that irradiates an object with X-rays generated by an X-ray generator, detects the X-rays that pass through the object with an X-ray detector, converts them into electrical signals, and generates an X-ray image based on the electrical signals. An operator such as a doctor or technician operates the X-ray diagnostic device to generate X-ray images, and the doctor diagnoses the object based on the generated X-ray images.

[0003] The X-ray generation unit in this X-ray diagnostic device is provided with an X-ray tube that generates X-rays themselves, and an X-ray aperture that applies aperture to the generated X-rays. The operator uses this X-ray aperture to avoid X-ray irradiation to unnecessary parts of the subject, thereby reducing the amount of X-ray irradiation to the subject. This X-ray aperture has, for example, four aperture blades, and two blades facing each other in the vertical direction and two blades facing each other in the horizontal direction are controlled to open and close symmetrically up and down and left and right with respect to the center of the effective field of view area of ​​the X-ray detector. That is, when the operator operates the operating device, the two blades facing each other in the vertical direction are controlled to open and close in conjunction with each other, and independently, the two blades facing each other in the horizontal direction are controlled to open and close in conjunction with each other.

[0004] There are also X-ray diagnostic devices that have a function of concentrically setting an area with a field of view size smaller than the effective field of view of the X-ray detector as a set field of view area and enlarging and displaying this small set field of view area. In this case as well, the X-ray aperture is controlled to open and close symmetrically up and down and left and right with respect to the center of the effective field of view of the X-ray detector.

[0005] On the other hand, there are also X-ray diagnostic devices that have a function of arbitrarily setting an area of ​​a field of view smaller than the effective field of view of the X-ray detector as a set field of view within the effective field of view of the X-ray detector and enlarging and displaying this small set field of view. In order to realize a set field of view with a small field of view, the X-ray aperture controls four blades at the top, bottom, left and right asymmetrically so that X-rays are irradiated onto an area of ​​the small field of view. However, when a small field of view is set, it is not possible to further narrow down the X-rays by operating the X-ray aperture using an operating device to open and close the four blades at the top, bottom and left and right. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2010-57663 A [Patent Document 2] JP 2008-29645 A Summary of the Invention [Problem to be solved by the invention]

[0007] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to make it possible to achieve further X-ray aperture even when a set field of view area with a small field of view size is set at any position within the effective field of view area in an X-ray diagnostic apparatus. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problem. Problems corresponding to the effects of each configuration shown in the embodiments described later can also be positioned as other problems. [Means for solving the problem]

[0008] An X-ray diagnostic apparatus according to an embodiment includes an X-ray generating unit that generates X-rays and has an X-ray aperture that applies aperture to the X-rays, an X-ray detector that detects the X-rays generated by the X-ray generating unit and that have passed through a subject, a field of view area setting unit that sets a set field of view area having a field of view size smaller than the effective field of view area of ​​the X-ray detector within the effective field of view area of ​​the X-ray detector, a reference point determination unit that determines a reference point of the aperture within the set field of view area, and an X-ray aperture adjustment unit that adjusts the X-ray aperture around the reference point within the set set field of view area based on the operation of an operating device. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram for explaining the configuration of an X-ray diagnostic apparatus according to an embodiment of the present invention. [Diagram 2] 2 is a block diagram illustrating the internal configuration of an X-ray generation unit of the X-ray diagnostic apparatus according to the present embodiment. FIG. [Diagram 3] FIG. 2 is a diagram showing an example of an operation device for opening and closing the blades of the X-ray aperture. [Figure 4] 13 is a diagram showing another example of an operating device for opening and closing the blades of the X-ray aperture. FIG. [Diagram 5] 2 is a functional block diagram illustrating functions realized by a processing circuit of the X-ray diagnostic apparatus according to the present embodiment reading out a program from a storage circuit and executing the program. FIG. [Figure 6] FIG. 4 is a flowchart illustrating an example of an X-ray aperture adjustment process executed in the X-ray diagnostic apparatus according to the present embodiment. [Figure 7] 2 is a diagram for explaining the relationship between an effective field of view area of ​​an X-ray detector in the X-ray diagnostic apparatus according to the present embodiment and a set effective field of view area that is set within this effective field of view area. FIG. [Figure 8] 11 is a diagram showing another set field of view area set in the effective field of view area of ​​the X-ray detector in the X-ray diagnostic apparatus according to the present embodiment. FIG. [Figure 9] 11 is a diagram illustrating the relationship between a set visual field area set by an operator and an image display area of ​​a display. FIG. [Figure 10]13A and 13B are diagrams illustrating the positional relationship between a set visual field area set within an effective visual field area and a reference point. [Figure 11] 13 is a diagram illustrating another example of the positional relationship between the set visual field area set within the effective visual field area and the reference point. FIG. [Figure 12] 13 is a diagram illustrating yet another example of the positional relationship between a set visual field area set within the effective visual field area and a reference point. FIG. [Figure 13] 13 is a diagram illustrating yet another example of the positional relationship between a set visual field area set within the effective visual field area and a reference point. FIG. [Figure 14] 11 is a diagram illustrating the relationship between a set visual field area set by an operator and a reference point also set by the operator. FIG. [Figure 15] FIG. 13 is a diagram showing an example of a display on a display when an operator determines a reference point. [Figure 16] FIG. 13 is a diagram showing an example of a perspective image displayed in an image display area of ​​a display. [Figure 17] 3A to 3C are diagrams illustrating the operation of blades of an X-ray aperture provided in the X-ray generation unit of the X-ray diagnostic apparatus according to the present embodiment. [Figure 18] 1A to 1C are diagrams illustrating an example of the opening and closing movement of four blades in the X-ray aperture of the X-ray generating unit. [Figure 19] 1 is a diagram for explaining an effective visual field area, a set visual field area, and an arrangement of four blades. FIG. [Figure 20] 1(a) to 1(c) are diagrams illustrating an example of the opening and closing operation of four blades. [Figure 21] 13(a) to 13(c) are diagrams showing other examples of the opening and closing operations of four blades. [Figure 22] 6(a) to 6(c) are diagrams for explaining an example of the definition of the aperture of the X-ray aperture in the X-ray diagnostic apparatus according to this embodiment. [Diagram 23] 6(a) to 6(c) are diagrams for explaining another example of the definition of the aperture of the X-ray aperture in the X-ray diagnostic apparatus according to this embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an X-ray diagnostic apparatus according to an embodiment will be described with reference to the drawings. In the following description, components having substantially the same functions and configurations are denoted by the same reference numerals, and repeated description will be given only when necessary.

[0011] [First embodiment] 1 is a block diagram for explaining the configuration of an X-ray diagnostic apparatus 1 according to the first embodiment. As shown in this Fig. 1, the X-ray diagnostic apparatus 1 according to the present embodiment is configured to include an imaging device 10 and a control device 20.

[0012] The imaging device 10 has an arm 11, and an X-ray generating unit 12 is provided at one end of the arm 11. A high voltage and a filament current are supplied to the X-ray generating unit 12 from a high voltage generator 14, and the X-ray generating unit 12 generates X-rays based on these. The X-rays generated by the X-ray generating unit 12 are irradiated onto a subject P on a bed BD.

[0013] An X-ray detector 16 is provided at the other end of the arm 11. The X-ray detector 16 is composed of, for example, a flat panel detector (FPD) having a plurality of pixels arranged two-dimensionally, and each pixel detects X-rays generated by the X-ray generation unit 12 and converts the detected X-rays into an electric signal. The electric signal is converted from an analog electric signal to digital data by an analog digital converter (not shown) and output to an image generating circuit 22 of the control device 20. The driving circuit 18 rotates the arm 11 to which the X-ray generation unit 12 and the X-ray detector 16 are attached, about a predetermined rotation axis.

[0014] The control device 20 comprises an image generating circuit 22, an input interface 24, a memory circuit 26, a display 28, an X-ray control circuit 30, a drive control circuit 32, and a processing circuit 34, which are interconnected by an internal bus or the like.

[0015] The image generating circuitry 22 performs preprocessing on the digital data output from the X-ray detector 16 to generate an X-ray image. Here, the preprocessing is, for example, processing related to correction of non-uniform sensitivity of each pixel in the X-ray detector 16, correction of missing pixels, etc. The image generating circuitry 22 outputs the generated X-ray image to the memory circuitry 26 for storage. The image generating circuitry 22 is, for example, configured with a processor, and is realized by reading out a program required for generating an X-ray image from the memory circuitry 26 and executing it.

[0016] The input interface 24 is configured by a device that enables an operator operating this X-ray diagnostic apparatus 1 to input various instructions, commands, information, selections, settings, etc., to the X-ray diagnostic apparatus 1. For example, this input interface 24 can be configured by a touch panel type liquid crystal display, a mouse, a keyboard, switch buttons, a trackball, etc., and the operator can give various instructions to the X-ray diagnostic apparatus 1 by operating this input interface 24.

[0017] The memory circuitry 26 is configured with, for example, a hard disk drive or an SSD (Solid State Drive), and stores various data. In this embodiment, in particular, the X-ray image generated by the image generating circuitry 22 and instructions and information input by the operator via the input interface 24 are stored and memorized. The memory circuitry 26 outputs the stored X-ray image data to the display 28 or to the outside of the control device 20 based on various commands.

[0018] The display 28 is configured by, for example, a liquid crystal display, an organic electro-luminescence display, a plasma display, etc., and displays various information. In particular, in this embodiment, the display 28 displays the X-ray image stored in the memory circuitry 26.

[0019] Based on instructions from the processing circuit 34, the X-ray control circuit 30 controls the high voltage generator 14 of the imaging device 10, causing the high voltage generator 14 to generate a high voltage and filament current according to the X-ray conditions and supply them to the X-ray generation unit 12.

[0020] The drive control circuit 32 controls the drive circuit 18 of the image capturing device 10 based on instructions from the processing circuit 34, and rotates the arm 11 of the image capturing device 10 around a predetermined rotation axis.

[0021] The processing circuitry 34 performs overall control of the X-ray diagnostic apparatus 1. That is, the processing circuitry 34 comprehensively controls various components included in the X-ray diagnostic apparatus 1, and causes the X-ray diagnostic apparatus 1 to perform various operations in this embodiment. The processing circuitry 34 is configured by, for example, a processor, and performs overall control by reading out a program required for controlling the X-ray diagnostic apparatus 1 from the storage circuitry 26 and executing it.

[0022] Fig. 2 is a block diagram for explaining the internal configuration of the X-ray generation unit 12 of the X-ray diagnostic apparatus 1 according to this embodiment. As shown in Fig. 2, the X-ray generation unit 12 according to this embodiment is configured to include an X-ray tube 12a that irradiates X-rays to the subject P, and an X-ray aperture 12b that applies aperture to the X-rays irradiated from the X-ray tube 12a.

[0023] The X-ray tube 12a is a vacuum tube that generates X-rays. The X-ray tube 12a includes, for example, a tube, a filament (cathode) provided in the tube, and a tungsten anode. The X-ray tube 12a accelerates thermoelectrons emitted from the filament by a high voltage and causes the accelerated thermoelectrons to collide with the tungsten anode, thereby generating X-rays.

[0024] The X-ray aperture 12b is located between the X-ray tube 12a and the X-ray detector 16, and is made of lead as a metal plate. The X-ray aperture 12a blocks X-rays outside the aperture area, thereby adjusting the X-rays generated by the X-ray tube 12a so that they are not irradiated onto areas other than the area of ​​interest of the subject P. For example, the X-ray aperture 12b has four blades, and the area blocked by X-rays, that is, the field of view size, is adjusted by sliding these blades. The blades of the X-ray aperture 12b can be opened and closed by the operator operating a control in the input interface 24.

[0025] Fig. 3 is a diagram showing an example of an operation device 40 for opening and closing the blades of the X-ray aperture 12b. The operation device 40 shown in Fig. 3 is a part of the above-mentioned input interface 24, and an operator operates the operation device 40 to open and close the blades of the X-ray aperture 12b.

[0026] 3, the operating device 40 according to this embodiment includes two operating levers 42 and 44. The operating lever 42 is a lever for opening and closing the two upper and lower blades, and the operating lever 44 is a lever for opening and closing the two left and right blades.

[0027] Specifically, when the operator tilts the operation lever 42 in the opening direction D1, the two upper and lower blades of the X-ray aperture 12b can be opened. On the other hand, when the operator tilts the operation lever 42 in the closing direction D2, the two upper and lower blades of the X-ray aperture 12b can be closed. Furthermore, when the operator tilts the operation lever 44 in the opening direction D3, the two left and right blades of the X-ray aperture 12b can be opened. On the other hand, when the operator tilts the operation lever 44 in the closing direction D4, the two left and right blades of the X-ray aperture 12b can be closed.

[0028] In addition, in Fig. 3, the case where the operating device 40 for opening and closing the blades of the X-ray aperture 12b is provided with two operating levers 42, 44 is illustrated, but the number of operating levers does not necessarily have to be two. For example, as shown in Fig. 4, one operating lever 46 may be tilted in an opening direction D1, a closing direction D2, an opening direction D3, and a closing direction D4 to open and close the two upper and lower blades and the two left and right blades, respectively.

[0029] In this case, the operating lever 46 may be tilted in an oblique direction so that the four blades can be opened and closed simultaneously. For example, the operating lever 46 may be tilted in an oblique direction between the opening direction D1 and the opening direction D3 so that the four blades can be opened simultaneously. Also, for example, the operating lever 46 may be tilted in an oblique direction between the closing direction D2 and the closing direction D4 so that the four blades can be closed simultaneously.

[0030] Alternatively, four operation buttons may be displayed on a touch panel type liquid crystal display provided as the input interface 24. These four operation buttons are respectively composed of a button for opening the two upper and lower blades, a button for closing the two upper and lower blades, a button for opening the two left and right blades, and a button for closing the two upper and lower blades, and the operator operates any of these four operation buttons to open or close the four blades.

[0031] 3 and 4, the operation modes are described in which the four blades are opened and closed while the operating levers 42, 44, 46 are tilted diagonally, and the opening and closing of the four blades is not performed when the operating levers 42, 44, 46 are in the upright position, but the operation modes of the operating levers 42, 44, 46 are not limited to this. For example, the operating levers 42, 44, 46 may be configured as slide levers, and the position or tilt angle of the operating levers 42, 44, 46 may indicate the opening degree of each of the four blades.

[0032] Fig. 5 is a functional block diagram explaining functions realized by the processing circuitry 34 reading and executing a program from the storage circuitry 26. As shown in Fig. 5, the processing circuitry 34 according to this embodiment realizes a system control function 34a, a set field of view area setting function 34b, a reference point determination function 34c, and an X-ray aperture adjustment function 34d.

[0033] 5, the system control function 34a, the set field of view area setting function 34b, the reference point determination function 34c, and the X-ray aperture adjustment function 34d are realized by a single processing circuit 34. However, the processing circuit 34 may be configured by combining a plurality of independent processors, and each processor may execute a program to realize each function. The system control function 34a, the set field of view area setting function 34b, the reference point determination function 34c, and the X-ray aperture adjustment function 34d may be called a system control circuit, a set field of view area setting circuit, a reference point determination circuit, and an X-ray aperture adjustment circuit, respectively, and may be implemented as separate hardware circuits.

[0034] Of the functions realized in the processing circuit 34 shown in Figure 5, the system control function 34a constitutes the system processing unit of this embodiment, the set field of view area setting function 34b constitutes the field of view area setting unit of this embodiment, the reference point determination function 34c constitutes the reference point determination unit of this embodiment, and the X-ray aperture adjustment function 34d constitutes the X-ray aperture adjustment unit of this embodiment.

[0035] Fig. 6 is a diagram showing a flowchart for explaining an example of an X-ray aperture adjustment process executed by the X-ray diagnostic apparatus 1 according to this embodiment. The X-ray aperture adjustment process shown in Fig. 6 is a process that is automatically started when an operator operates the X-ray diagnostic apparatus 1 to start preparation for X-ray imaging or when fluoroscopic imaging is performed on the subject P using X-rays, and is executed by the processing circuitry 34. That is, the operator can adjust the X-ray aperture at any time, whether before or during irradiation of the subject P with X-rays.

[0036] In this X-ray aperture adjustment process, first, the set field of view area setting function 34b of the processing circuit 34 determines whether a set field of view area with a field of view size smaller than the effective field of view area of ​​the X-ray detector 16 has been set within the effective field of view area of ​​the X-ray detector 16, or whether a set field of view area that was once set has been changed and re-set (step S10).

[0037] 7 is a diagram for explaining the relationship between the effective field of view area N of the X-ray detector 16 in the X-ray diagnostic apparatus 1 according to this embodiment and a set effective field of view area set within this effective field of view area N. As shown in this Fig. 7, a range in which the X-ray detector 16 can effectively detect X-rays is set as the effective field of view area N. This is unique to the X-ray detector 16, and the X-ray detector 16 can detect X-rays generated by the X-ray generation unit 12 within the range of this effective field of view area N. In other words, the effective field of view area N is the maximum size of the field of view area in this X-ray detector 16.

[0038] The operator of the X-ray diagnostic device 1 can set the set visual field areas M1, M2, and M3 of any visual field size within this effective visual field area N. Inevitably, the visual field sizes of the set visual field areas M1, M2, and M3 are smaller than the visual field size of the effective visual field area N. In the example of FIG. 7, the center of the effective visual field area N and the center of the set visual field areas M1, M2, and M3 coincide with each other. In addition, in the example of FIG. 7, the visual field size of the set visual field area M2 is smaller than the visual field size of the set visual field area M1, and the visual field size of the set visual field area M3 is smaller than the visual field size of the set visual field area M2. Since the centers of the set visual field areas M1, M2, and M3 coincide with the center of the effective visual field area N, these three set visual field areas M1, M2, and M3 are arranged concentrically.

[0039] Fig. 8 is a diagram showing another set field of view area M set in the effective field of view area N of the X-ray detector 16 in the X-ray diagnostic apparatus 1 according to this embodiment. As shown in the example of Fig. 8, in this embodiment, the operator of the X-ray diagnostic apparatus 1 can set the set field of view area M of an arbitrary field of view size at an arbitrary position within the effective field of view area N. In other words, the center of the set field of view area M and the center of the effective field of view area N are at different positions.

[0040] The setting of the set visual field area M in step S10 can be performed by the operator by operating a touch panel display of the input interface 24, a mouse, etc. For example, when using a mouse, the operator can set the set visual field area M at a desired position and with a desired visual field size by pressing the left button to start dragging when the pointer is at the upper left end of the set visual field area M and ending the dragging when the pointer is at the lower right end of the set visual field area M.

[0041] 9 is a diagram for explaining the relationship between the set visual field area set by the operator and the image display area IMG of the display 28. As shown in this Fig. 9, regardless of the visual field size of the set visual field area M set by the operator, the size of the image display area IMG displayed on the display 28 is the same. In other words, the image display area IMG of the set visual field areas M, M1, M2, M3 with small visual field sizes and the image display area IMG of the effective visual field area N are all displayed on the display 28 with the same size. In other words, the set visual field areas M, M1, M2, M3 with small visual field sizes are enlarged and displayed in the image display area IMG of the display 28.

[0042] As shown in Fig. 6, if a set field of view area smaller than the effective field of view area of ​​the X-ray detector 16 is set within the effective field of view area of ​​the X-ray detector 16, or if a set field of view area once set is changed and reset (step S10: Yes), in the X-ray aperture adjustment process, the reference point of the aperture within the set field of view area M set in step S10 is determined by the reference point determination function 34c of the processing circuit 34 (step S12). This reference point is a central point when applying aperture to X-rays using the X-ray aperture. On the other hand, if a set field of view area smaller than the effective field of view area of ​​the X-ray detector 16 is set within the effective field of view area of ​​the X-ray detector 16, or if a set field of view area once set is not changed and reset (step S10: No), the process of step S12 is skipped.

[0043] 10(a) and 10(b) are diagrams for explaining the positional relationship between the set field of view area M and the reference point. In both of the examples of FIG. 10(a) and FIG. 10(b), the center of the set field of view area M is determined as the reference point RP. That is, the reference point determination function 34c of the processing circuit 34 identifies the center of the set field of view area M set by the operator in step S10, and automatically sets this center as the reference point RP. In the examples of FIG. 10(a) and FIG. 10(b), the operator does not need to specify or identify the reference point RP.

[0044] Also, when the operator moves the set visual field area M, the reference point determination function 34c of the processing circuit 34 automatically identifies the center of the set visual field area M after the movement again, and sets this center as the reference point RP. For example, even when the operator moves the set visual field area M from the position in Fig. 10(a) to the position in Fig. 10(b), the reference point determination function 34c of the processing circuit 34 automatically sets the reference point RP at the center of the set visual field area M in Fig. 10(b). That is, in the examples of Fig. 10(a) and Fig. 10(b), the reference point RP also moves automatically.

[0045] FIG. 11 is a diagram for explaining another example of the positional relationship between the set field of view area and the reference point RP. In the example of FIG. 11, the reference point RP is determined based on the type of examination performed on the subject P. FIG. 11 shows an example in which the X-ray imaging performed by the X-ray diagnostic device 1 is a urological examination. In a urological examination, it is necessary to X-ray image the bladder, urinary tract, etc., so even if the field of view size is changed to the set field of view areas M1, M2, and M3, the lower side of the set field of view areas M1, M2, and M3 overlaps with the lower side of the effective field of view area N, and the vertical normal depth center line of the set field of view areas M1, M2, and M3 overlaps with the vertical center line of the effective field of view area N. In addition, the reference point RP of the set field of view areas M1, M2, and M3 is fixed to the center of the lower side of the set field of view areas M1, M2, and M3. That is, even if the operator changes the visual field size of the set visual field areas M1, M2, M3, the reference point determination function 34c of the processing circuit 34 sets the reference point RP at the center of the lower side of the set visual field area.

[0046] FIG. 12 is a diagram for explaining yet another example of the positional relationship between the set field of view area and the reference point RP. In the example of FIG. 12, the reference point RP is also determined based on the type of examination performed on the subject P. However, FIG. 12 illustrates a case where X-ray imaging performed by the X-ray diagnostic device 1 is performed for forming a shunt in the arm. Since a shunt is formed in the arm, even if the field of view size is changed to set field of view areas M1, M2, and M3, the right side (left side) of the set field of view areas M1, M2, and M3 is changed so that it overlaps with the right side (left side) of the effective field of view area N, and the horizontal center line of the set field of view areas M1, M2, and M3 overlaps with the horizontal center line of the effective field of view area N. In addition, the reference point determination function 34c of the processing circuit 34 fixes the reference point RP to the center of the right side (left side) of the set field of view area set by the operator. Therefore, even if the operator changes the field of view size to set field of view areas M1, M2, and M3, the reference point RP is fixed at the center of the right side (left side) of the set field of view area.

[0047] The type of examination to be performed by the X-ray diagnostic apparatus 1 is stored in the memory circuitry 26, for example, for each subject P. The system control function 34a, which performs overall control of the X-ray diagnostic apparatus 1, reads information on the examination contents of the subject P to be X-ray-imaged from the memory circuitry 26, and identifies the examination type. Based on the identified examination type, the reference point determination function 34c determines the position of the reference point RP. That is, in the example of FIG. 11, based on the information that the examination type is a urological examination, the reference point determination function 34c determines the reference point RP to be the center of the lower side of the set field of view area. In the example of FIG. 12, based on the information that the examination type is a shunt formation, the reference point determination function 34c determines the reference point RP to be the center of the right side (or the center of the left side) of the set field of view area.

[0048] Depending on the type of examination, the components constituting the X-ray diagnostic device 1 may interfere with the X-ray imaging of the subject P. In this way, when the components of the X-ray diagnostic device 1 interfere with the X-ray imaging, for example, as shown in FIG. 13, even if the field of view size is changed to the set field of view areas M1, M2, and M3, the lower right corners of the set field of view areas M1, M2, and M3 are changed so as to overlap with the lower right corner of the effective field of view area N. In addition, the reference point determination function 34c of the processing circuit 34 sets the reference point RP to the lower right corner of the set field of view area with less interference. Therefore, even if the operator changes the field of view size to the set field of view areas M1, M2, and M3, the reference point determination function 34c keeps the reference point RP fixed to the lower right corner of the set field of view area. Whether or not the X-ray diagnostic device 1 interferes with the X-ray imaging can be determined based on, for example, the above-mentioned examination type.

[0049] Alternatively, the reference point determination function 34c of the processing circuit 34 may determine the reference point based on a designation by an operator. For example, the operator may set the reference point by operating a touch panel display of the input interface 24, a mouse, or the like.

[0050] FIG. 14 is a diagram for explaining the relationship between the set visual field area set by the operator and the reference point set by the operator. FIG. 15 is a diagram showing an example of the display of the display 28 when the operator determines the reference point. As shown in these FIGS. 14 and 15, the operator operates, for example, a mouse to set the reference point RP at a desired position. Specifically, the mouse pointer is moved to a position in the image display area IMG where the reference point RP is to be set, and the position is determined by clicking the left button. Since the image display area IMG of the display 28 displays the enlarged set visual field area M set in step S10, the reference point determination function 34c of the processing circuit 34 sets the reference point RP at the corresponding position of the set visual field area M in FIG. 14.

[0051] Alternatively, the reference point determination function 34c of the processing circuit 34 may perform image analysis of a fluoroscopic image taken using X-rays, identify a specific part, and determine the identified specific part as the reference point. For example, when the liver is the specific part, the reference point determination function 34c identifies the liver by image analysis of the fluoroscopic image, and determines the identified liver as the reference point. In this case, since a specific part such as the liver has a predetermined area, the reference point determination function 34c sets the reference point at, for example, the geometric center of the specific part.

[0052] Fig. 16 is a diagram showing an example of a fluoroscopic image displayed in an image display area IMG of the display 28. As shown in Fig. 16, the reference point determination function 34c performs image analysis of the fluoroscopic image to identify a specific region SP. The system control function 34a, which performs overall control of the X-ray diagnostic apparatus 1, reads information on the examination contents of the subject P to be X-ray-picked from the memory circuitry 26 to determine which organ or region is to be the specific region. The reference point determination function 34c calculates the geometric center, which is the geometric center of the specific region SP identified by the image analysis, and determines the calculated geometric center as the reference point RP.

[0053] 6, in the X-ray aperture adjustment process, the X-ray aperture adjustment function 34d of the processing circuit 34 determines whether or not the operator has operated the operation device (step S14). If the operation device has not been operated (step S14: No), the process skips the next step S16 and returns to the above-mentioned step S10.

[0054] On the other hand, if the operator operates the control device (step S14: Yes), the X-ray aperture adjustment function 34d of the processing circuitry 34 adjusts the X-ray aperture (step S16). Specifically, the X-ray aperture adjustment function 34d of the processing circuitry 34 cooperates with the system control function 34a to open and close the blades of the X-ray aperture 12b of the X-ray generation unit 12 based on the operator's operation of the control device, thereby adjusting the aperture.

[0055] Fig. 17 is a diagram for explaining the operation of the blades of the X-ray aperture 12b included in the X-ray generation unit 12 of the X-ray diagnostic apparatus 1 according to this embodiment, showing a plan view of the X-ray aperture 12b as viewed from the X-ray tube 12a side. As shown in Fig. 17, the X-ray aperture 12b has two upper and lower blades 120a and 120b and two left and right blades 120c and 120d. Each of these four blades 120a to 120d can move from one side to the other side of the effective field of view area N.

[0056] Specifically, side 122a on the movement direction side of first blade 120a is located at first side Na of effective visual field area N in a fully open state. As the operator performs an operation to close first blade 120a, side 122a on the movement direction side of first blade 120a moves toward second side Nb opposite to first side Na of effective visual field area N. Then, side 122a on the movement direction side of first blade 120a reaches second side Nb of effective visual field area N in a fully closed state.

[0057] In contrast, side 122b on the movement direction side of second blade 120b is located at the second side Nb of the effective visual field area N in the fully open state. As the operator performs an operation to close second blade 120b, side 122b on the movement direction side of second blade 120b moves toward first side Na facing the second side Nb of the effective visual field area N. Then, side 122b on the movement direction side of second blade 120b reaches the first side Na of the effective visual field area N in the fully closed state.

[0058] On the other hand, side 122c on the movement direction side of third blade 120c is located at the third side Nc of the effective visual field area N in the fully open state. As the operator performs an operation to close this third blade 120c, side 122c on the movement direction side of third blade 120c moves toward fourth side Nd facing the third side Nc of the effective visual field area N. Then, side 122c on the movement direction side of third blade 120c reaches the fourth side Nd of the effective visual field area N in the fully closed state.

[0059] In contrast, side 122d on the movement direction side of fourth blade 120d is located at the fourth side Nd of the effective visual field area N in the fully open state. As the operator performs an operation to close this fourth blade 120d, side 122d on the movement direction side of fourth blade 120d moves toward the third side Nc facing the fourth side Nd of the effective visual field area N. Then, side 122d on the movement direction side of fourth blade 120d reaches the third side Nc of the effective visual field area N in the fully closed state.

[0060] The above is the mechanical movable range of the four blades 120a-120d, but in this embodiment, the four blades 120a-120d open and close with reference to a reference point RP set by an operator. Fig. 18 is a diagram for explaining an example of the movement of the opening and closing operation of the four blades 120a-120d in the X-ray aperture 12b. In the example of Fig. 18, the four blades 120a-120d move symmetrically with respect to the reference point RP. That is, the opening and closing operation is performed so that the opening 124 formed by the four blades 120a-120d is vertically symmetrical and horizontally symmetrical with respect to the reference point.

[0061] Specifically, the two upper and lower blades 120a, 120b open and close so that the distance from the reference point RP to the side 122a on the moving direction side of the first blade 120a is the same as the distance from the reference point RP to the side 122b on the moving direction side of the second blade 120b. Similarly, the two upper and lower blades 120c, 120d open and close so that the distance from the reference point RP to the side 122c on the moving direction side of the third blade 120c is the same as the distance from the reference point RP to the side 122d on the moving direction side of the fourth blade 120d.

[0062] Fig. 19 is a diagram for explaining the arrangement of the effective visual field area N, the set visual field area M, and the four blades 120a to 120d. As shown in Fig. 19, the set visual field area M is defined by using the four blades 120a to 120d. In Fig. 19, the sides 122a to 122d on the movement direction side of the four blades 120a to 120d match the positions of the four sides that define the set visual field area M. Therefore, in the set visual field area M, the positions of the four blades 120a to 120 shown in Fig. 19 represent the positions in a fully open state. In other words, fully open when the set field of view M is set means that the edges 122a, 122b in the movement direction of the two opposing blades 120a, 120b on the top and bottom have each reached both opposing sides of the set field of view M, and the edges 122c, 122d in the movement direction of the two opposing blades 120c, 120d on the left and right have each reached both opposing sides of the set field of view M.

[0063] On the other hand, when the set visual field area M is set, "fully closed" means that at least two blades are joined at the reference point RP shown in FIG. 19. In other words, "fully closed" means that the sides 122a and 122b in the moving direction of two blades 120a and 120b facing each other vertically have reached the reference point RP. Alternatively, it means that the sides 122c and 122d in the moving direction of two blades 120c and 120d facing each other horizontally have reached the reference point RP. Of course, in the fully closed state, each of the four blades 120a to 120d may reach the reference point RP.

[0064] Furthermore, in the X-ray diagnostic apparatus 1 according to this embodiment, when a set field of view area M is set, even if the operator operates the operation device, the four blades 120a-120d are configured not to open beyond the set field of view area M. In other words, the state of the blades 120a-120d shown in Fig. 19 is the maximum opening degree, and the blades 120a-120d do not open any further.

[0065] Specifically, when either of the sides 122a, 122b in the moving direction of the two blades 120a, 120b opposing each other vertically or the sides 122c, 122d in the moving direction of the two blades 120c, 120d opposing each other horizontally reaches an edge of the set field of view M, the blade stops at the edge of the set field of view M. This makes it possible to prevent the X-ray aperture 12b from opening to an area larger than the set field of view M once set, regardless of how the operator operates the operation device.

[0066] Figures 20(a) to 20(c) are diagrams showing an example of the opening and closing operation of the four blades 120a to 120d. In the example of Figures 20(a) to 20(c), the two upper and lower blades 120a and 120b open and close symmetrically from top to bottom with respect to a reference point RP. Meanwhile, the two left and right blades 120c and 120d open and close symmetrically from left to right with respect to the reference point RP.

[0067] For this reason, when the two blades 120c, 120d gradually open from the state shown in Fig. 20(a), one blade 120d reaches the edge of the set visual field area M and cannot open any further, as shown in Fig. 20(b). On the other hand, the other blade 120c can theoretically open any further.

[0068] 20(b), that is, when any of the four blades 120a to 120d reaches the edge of the set field of view area M, none of the four blades of the X-ray aperture 12b can be made to open any further. In other words, the other three blades also stop at that position.

[0069] 20(c), even if any one of the four blades 120a to 120d reaches the edge of the set field of view region M, the other blades of the X-ray aperture 12b can be opened until they each reach the edge of the set field of view region M. In other words, each of the four blades can reach the edge of the set field of view region M.

[0070] 21(a) to 21(c) are diagrams showing another example of the opening and closing operation of the four blades 120a to 120d. In the example of Fig. 21(a) to 21(c), the four blades 120a to 120d open and close so that the ratio of the open distance from the reference point RP to the distance from the reference point RP to the edge of the set field of view M is the same.

[0071] In other words, the two upper and lower blades 120a, 120b open and close so that the distance from the already opened reference point RP to the sides 122a, 122b in the movement direction of the blades 120a, 120b is in the same ratio to the distance from the reference point RP to the two opposing sides Ma, Mb of the set field of view area M.

[0072] On the other hand, the two left and right blades 120c, 120d open and close so that the distance from the already opened reference point RP to the sides 122c, 122d in the movement direction of the blades 120c, 120d is in the same ratio to the distance from the reference point RP to the two opposing sides Mc, Md of the set field of view area M.

[0073] 21, the two opposing blades simultaneously reach the edge of the set field of view M. That is, the two upper and lower blades 120a, 120b simultaneously reach the two opposing sides Ma, Mb of the set field of view M. In addition, the two left and right blades 120c, 120d simultaneously reach the two opposing sides Mc, Md of the set field of view M.

[0074] Specifically, Fig. 21(a) shows a state in which the left and right blades 120c, 120d are open 20%, Fig. 21(b) shows a state in which they are open 50%, and Fig. 21(c) shows a state in which they are open 80%. Note that in both the examples of Fig. 20 and Fig. 21, during the closing operation, the two opposing blades are fully closed at the same time. In other words, when fully closed, the two opposing blades reach the reference point RP at the same time.

[0075] 22(a) to 22(c) are diagrams for explaining an example of the definition of the opening of the X-ray aperture 12b in the X-ray diagnostic apparatus 1 according to this embodiment. As shown in FIG. 22(a), in this embodiment, the reference point RP can be set at a position shifted from the center of the set field of view area M. In that case, the distance from the reference point RP to the edge of the set field of view area M will be different in all four directions. In other words, the moving distances to the edge of the set field of view area M for two opposing blades that simultaneously open and close will be different.

[0076] For this reason, in this embodiment, the opening degree is defined based on the longer distance from the reference point to the end of the set field of view M. That is, as shown in FIG. 22(b), when the two blades 120c and 120d facing each other on the left and right are fully closed, these two blades 120c and 120d are in contact at the reference point RP. As described in FIG. 20, when the opening operation is performed symmetrically on the left and right with respect to the reference point RP, the right blade 120d reaches the end of the set field of view M first, as shown in FIG. 22(c). However, at this time, the left blade 120c is still only half open. For this reason, the opening degree of the X-ray aperture 12b shown in FIG. 22(c) is 50%.

[0077] 22(c), the right blade 120d will not open any further because it has already reached the edge of the set field of view area M. On the other hand, the left blade 120c opens further when the operator increases the opening, and when it reaches the edge of the set field of view area M, the opening of this X-ray aperture 12b becomes 100%.

[0078] On the other hand, as described in Fig. 21, if the opening operation is performed so that the distance from the reference point RP to the remaining distance to the edge of the set field of view M has the same ratio, the opening degree becomes 0% when fully closed and 100% when fully open, as shown in Figs. 23(a) to 23(c). In other words, if the reference point RP is set at the position shown in Fig. 23(a), the two left and right blades 120c and 120d are in a fully closed state, resulting in the state shown in Fig. 23(b). In other words, the left blade 120c and the right blade 120d are in contact at the reference point RP.

[0079] When the operator increases the opening of the X-ray aperture 12b and the opening reaches 50%, the two left and right blades 120c, 120d reach the state shown in Fig. 23(c). That is, for the two left and right blades 120c, 120d, the ratio of the distance opened from the reference point RP to the remaining distance to the edge of the set field of view M is both 50%. When the operator further increases the opening, the two left and right blades 120c, 120d open further and each simultaneously reaches the edge of the set field of view M. The opening of the X-ray aperture 12b at this time is 100%.

[0080] After the X-ray aperture 12b is adjusted in step S16 based on the operation of the operation device by the operator, the X-ray aperture adjustment process according to this embodiment returns to step S10 described above.

[0081] As described above, according to the X-ray diagnostic apparatus 1 of this embodiment, the operator can set the set field of view area M at any position within the effective field of view area N, and then set the reference point RP at any position within the set field of view area M. Therefore, unlike the conventional method, it is no longer necessary to move the subject P or the bed BD in order to move the area of ​​interest in the subject P to the center of the effective field of view area N, and the burden on the subject P during X-ray imaging can be reduced.

[0082] In other words, no matter where the region of interest of the subject P is located within the effective field of view N of the X-ray detector 16, the X-rays can be focused using the X-ray aperture 12b by setting the set field of view M and setting the reference point RP at the position of the region of interest without moving the subject P. This reduces the burden on the subject P and the amount of X-ray exposure to the subject P.

[0083] According to such an X-ray diagnostic apparatus 1, even in the case of, for example, X-ray imaging for inserting a catheter into a subject P, there is no need to move the subject P, so that the catheter can be inserted while performing X-ray imaging more safely.

[0084] Furthermore, since the operator can open and close the blades of the X-ray aperture 12b using the above-mentioned operation device 40, the same operability as in the past can be provided to the operator. In other words, once the operator sets the set field of view area M within the effective field of view area N and sets the reference point RP, the same operability as in the past can be provided for the opening and closing of the X-ray aperture 12b.

[0085] In the above embodiment, the aperture operation of the X-ray aperture 12b has been described using an example in which the X-ray aperture 12b has four blades 120a to 120d, but the number of blades of the X-ray aperture 12b is not limited to four and is arbitrary. For example, the X-ray aperture 12b may have three, six, eight, etc. blades. In any case, the blades of the X-ray aperture 12b open and close with respect to a set reference point RP.

[0086] In addition, in this embodiment, the terms up, down, left, right, and so on are used as information for identifying the blades of the X-ray aperture 12b. However, these terms are used for convenience in identifying and specifying the multiple blades, and should not be construed as limiting the absolute positional relationship or physical positions of these blades.

[0087] In the above description, an example has been described in which the "processor" in the processing circuit 34 reads out and executes a program corresponding to each processing function from a storage circuit, but the embodiment is not limited to this. The term "processor" refers to circuits such as a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a programmable logic device (e.g., a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)). When the processor is, for example, a CPU, the processor realizes each processing function by reading out and executing a program stored in a storage circuit. On the other hand, when the processor is, for example, an ASIC, instead of storing the program in a storage circuit, the processing function is directly incorporated as a logic circuit in the circuit of the processor. Note that each processor in this embodiment is not limited to being configured as a single circuit for each processor, and may be configured as one processor by combining multiple independent circuits to realize its processing function. Furthermore, multiple components in FIG. 1 may be integrated into one processor to realize the processing functions.

[0088] Although several embodiments have been described above, these embodiments are presented only as examples and are not intended to limit the scope of the invention. The novel device and method described in this specification can be implemented in various other forms. In addition, various omissions, substitutions, and modifications can be made to the forms of the device and method described in this specification without departing from the spirit of the invention. The appended claims and their equivalents are intended to include such forms and modifications that fall within the scope and spirit of the invention. [Explanation of symbols]

[0089] 1...X-ray diagnostic device, 10...imaging device, 11...arm, 12...X-ray generating unit, 12a...X-ray tube, 12b...X-ray aperture, 14...high voltage generator, 16...X-ray detector, 18...drive circuit, 20...control device, 22...image generating circuit, 24...input interface, 26...memory circuit, 28...display, 30...X-ray control circuit, 32...drive control circuit, 34...processing circuit, 34a...system control function, 34b...set field of view area setting function, 34c...reference point determination function, 34d...adjustment function, 40...operation device, 42...operation lever, 44...operation lever, 46...operation lever, 120a-120d...blade, 122a-122d...edge, 124...opening, D1...opening direction, D2...closing direction, D3...opening direction, D4...closing direction, IMG...image display area, M...set field of view area, M1...set field of view area, M2...set field of view area, M3...set field of view area, Ma-Md...edge, N...effective field of view area, Na-Nd...edge, P...subject, RP...reference point, SP...area

Claims

1. An X-ray generating unit that generates X-rays and has an X-ray aperture that applies aperture to the X-rays; an X-ray detector that detects X-rays generated by the X-ray generating unit and passed through a subject; a field of view setting unit that sets a set field of view having a field of view size smaller than the effective field of view area of ​​the X-ray detector within the effective field of view area of ​​the X-ray detector; a reference point determination unit that determines a reference point of a diaphragm within the set field of view; an X-ray aperture adjustment unit that adjusts the X-ray aperture around the reference point in the set field of view area based on an operation of an operating device; Equipped with The X-ray aperture includes two blades, one on the left and one on the right, and one on the top and bottom, The X-ray aperture adjustment unit includes: Based on the operation of the controller by an operator, the two left and right blades are opened and closed, and the two upper and lower blades are opened and closed, based on the reference point. An X-ray diagnostic device that opens and closes the two left and right blades and the two top and bottom blades so that the ratio of the open distance based on the reference point to the distance from the reference point to the edge of the set field of view area is the same.

2. The X-ray diagnostic apparatus according to claim 1 , wherein the reference point determination unit determines the reference point at a center of the set field of view area.

3. The X-ray diagnostic apparatus according to claim 1 , wherein the reference point determination unit determines the reference point based on a designation by an operator.

4. 2. The X-ray diagnostic apparatus according to claim 1, wherein the reference point determination unit performs image analysis of a fluoroscopic image taken using X-rays, identifies a specific portion, and determines the identified specific portion as the reference point.

5. The X-ray diagnostic apparatus according to claim 1 , wherein the reference point determination unit determines the reference points based on a type of examination performed on the subject.

6. The X-ray aperture adjustment unit includes: By the closing operation, the two left and right blades and the two upper and lower blades reach the reference point simultaneously and are fully closed, By the opening operation, the two left and right blades and the two upper and lower blades reach the ends of the set field of view simultaneously and are fully opened. In this manner, the two left and right blades and the two upper and lower blades are opened and closed.

2. The X-ray diagnostic apparatus according to claim 1.

7. An X-ray generating unit that generates X-rays and has an X-ray aperture that applies aperture to the X-rays; an X-ray detector that detects X-rays generated by the X-ray generating unit and passed through a subject; a field of view setting unit that sets a set field of view having a field of view size smaller than the effective field of view area of ​​the X-ray detector within the effective field of view area of ​​the X-ray detector; a reference point determination unit that determines a reference point of a diaphragm within the set field of view; an X-ray aperture adjustment unit that adjusts the X-ray aperture around the reference point in the set field of view area based on an operation of an operating device; A control method for an X-ray diagnostic apparatus comprising: The X-ray aperture includes two blades, one on the left and one on the right, and one on the top and bottom, The X-ray aperture adjustment unit includes: Based on the operation of the controller by an operator, the two left and right blades are opened and closed, and the two upper and lower blades are opened and closed, based on the reference point. A control method for an X-ray diagnostic device, which opens and closes the two left and right blades and the two top and bottom blades so that the ratio of the open distance from the reference point to the distance from the reference point to the edge of the set field of view area is the same.

Images