WO2022107496A1

WO2022107496A1 - Radiation diagnostic device

Info

Publication number: WO2022107496A1
Application number: PCT/JP2021/037584
Authority: WO
Inventors: 浩一北野
Original assignee: 富士フイルム株式会社
Priority date: 2020-11-20
Filing date: 2021-10-11
Publication date: 2022-05-27
Also published as: JPWO2022107496A1

Abstract

This radiation diagnostic device comprises: a radiation detector that detects radiation; an ultraviolet source that emits ultraviolet rays; a first power provision unit that provides power to a radiation detector; and a second power provision unit that is electrically separated from the first power provision unit and that provides power to the ultraviolet source.

Description

Radiation diagnostic equipment

The technique of this disclosure relates to a radiation diagnostic device.

Due to the recent epidemic of the new coronavirus (official name: SARS (Severe Acute Respiratory Syndrome) -Cov (Coronavirus) -2), outbreaks called clusters are occurring in medical institutions as well. For this reason, meticulous infection prevention measures are required for various tests and diagnoses at medical institutions. Sterilization by ultraviolet irradiation is effective as an infection prevention measure. It has also been reported that the new coronavirus is inactivated by irradiation with ultraviolet rays for several minutes.

As an infection prevention measure in medical institutions, it is known to provide an ultraviolet source in a lighting device in an operating room or the like (see, for example, International Publication No. 2019/186880). The ultraviolet source irradiates the area to be sterilized with ultraviolet rays.

Further, in the field of radiation diagnosis using a radiation detector that detects a radiation image, it is known that the radiation detector is irradiated with ultraviolet rays in order to eradicate the radiation detector (for example, Japanese Patent Application Laid-Open No. 2013). -Refer to JP-A-248124). Japanese Unexamined Patent Publication No. 2013-248124 describes that, in a mobile radiation diagnostic apparatus, an ultraviolet source for emitting ultraviolet rays toward a radiation detector is provided inside a storage folder for accommodating the radiation detector. ..

The lighting device described in International Publication No. 2019/186880 is provided with a light source for lighting (for example, a halogen lamp) for illuminating the surgical field in addition to the ultraviolet source. In the lighting device described in International Publication No. 2019/186880, the power supply unit that supplies power to the ultraviolet source and the power supply unit that supplies power to the lighting light source are connected in parallel. In this case, it is conceivable that the noise generated in each power supply unit affects each other between the ultraviolet source and the lighting light source. However, in International Publication No. 2019/186880, the influence of noise is not regarded as a problem.

In a radiation diagnostic apparatus provided with an ultraviolet source as described in JP-A-2013-248124, as described in International Publication No. 2019/186880, a power supply unit for supplying power to the ultraviolet source and radiation detection. When the power supply unit that supplies power to the device is connected in parallel, the influence of noise becomes a problem. Since the radiation detector used in the radiation diagnostic equipment has extremely high radiation detection sensitivity, even if the noise generated by the power supply section of the ultraviolet source is very small, it affects the radiation image detected by the radiation detector. May occur.

The technique of the present disclosure is intended to provide a radiation diagnostic apparatus capable of reducing the influence of noise on a radiation detector.

The radiation diagnostic apparatus of the present disclosure is electrically separated from a radiation detector that detects radiation, an ultraviolet source that emits ultraviolet rays, a first power supply unit that supplies power to the radiation detector, and a first power supply unit. It also includes a second power supply unit that supplies power to the ultraviolet source.

The ultraviolet rays are preferably deep ultraviolet rays having a central wavelength in the range of 200 nm or more and 280 nm or less.

The ultraviolet source preferably emits ultraviolet rays toward the radiation detector.

The radiation detector inputs to the sensor board a sensor board in which a plurality of pixels that generate and accumulate electric charges according to the incident amount of radiation are formed, and a drive signal for outputting charges from each of the plurality of pixels. A drive unit, a signal processing unit in which an electric signal corresponding to the electric charge output from the sensor board is input, and image data is generated and output based on the input electric signal, a sensor board, a drive unit, and signal processing. It is preferable to have a control unit for controlling the unit.

It is preferable that the sensor substrate has a conversion layer that directly converts radiation into electric charges, and the first power supply unit supplies a bias voltage to the conversion layer.

The ultraviolet source is preferably an excimer lamp.

It is preferable that the second power supply unit includes an inverter circuit.

The ultraviolet source is preferably an LED.

It is preferable to supply a pulsed drive current from the second power supply unit.

The first power supply unit and / or the second power supply unit is preferably a power supply circuit including a converter circuit that converts an AC voltage into a DC voltage.

It is preferable that the first power supply unit and the second power supply unit are electrically separated by a transformer having a secondary coil separately provided for the primary coil.

It is preferable that the reference electrode of the first power supply unit and the reference electrode of the second power supply unit are electrically separated.

It further includes a radiation source that emits radiation toward the radiation detector, and a third power supply unit that is electrically separated from the first power supply unit and the second power supply unit and supplies power to the radiation source. Is preferable.

The radiodiagnosis device is any one of a radiography device having a standing or recumbent radiography table, a mammography device, a radioscopic fluoroscopy device, a mobile radiography device, a mobile radioscopic radiography device, and a radiotomography device. Is preferable.

According to the technique of the present disclosure, it is possible to provide a radiation diagnostic apparatus capable of reducing the influence of noise on a radiation detector.

It is a figure which shows the mammography apparatus which is an example of a radiation diagnostic apparatus. It is a side view of the mammography apparatus which shows the radiation emission state. It is a side view of the mammography apparatus which shows the irradiation state of ultraviolet rays. It is a block diagram which shows the structure of a control device. It is a block diagram which shows the structure of a power supply device. It is a figure which shows the structure of a radiation detector. It is a figure which shows the structure of the ultraviolet ray source. It is a figure which shows the structure of a radiation tube. It is a figure which shows an example of the radiological imaging apparatus which has an imaging table. It is a figure which shows an example of the mobile radiation apparatus. It is a figure which shows an example of the radioscopic fluoroscopy apparatus. It is a figure which shows another example of the radioscopic fluoroscopy apparatus. It is a figure which shows an example of a radiation tomography apparatus.

As an example, as shown in FIGS. 1 and 2, the mammography apparatus 10 performs radiography with the breast M of the subject H as a subject. The mammography apparatus 10 irradiates the breast M with radiation R such as X-rays and γ-rays to generate a radiographic image RI of the breast M. The mammography apparatus 10 is an example of a "radiation diagnostic apparatus" according to the technique of the present disclosure.

The mammography apparatus 10 includes an apparatus main body 11 and a control device 12. The device main body 11 is installed, for example, in a radiography room of a medical facility. The control device 12 is installed in, for example, a control room next to the radiography room. The control device 12 is, for example, a desktop personal computer. The control device 12 is communicably connected to an image database (hereinafter abbreviated as image DB (Data Base)) server 14 via a network 13 such as a LAN (Local Area Network). The image DB server 14 is, for example, a PACS (Picture Archiving and Communication System) server, receives radiographic image RI from the mammography apparatus 10, and stores and manages the received radiographic image RI.

The terminal device 15 is connected to the network 13. The terminal device 15 is, for example, a personal computer used by a doctor who performs a medical examination using a radiographic image RI. The terminal device 15 receives the radiation image RI from the image DB server 14, and displays the received radiation image RI on the display.

The device main body 11 has a stand 20 and an arm 21. The stand 20 is composed of a pedestal 20A installed on the floor of the radiography room and a support column 20B extending in the height direction from the pedestal 20A. The arm 21 has a substantially C-shape when viewed from the side, and is connected to the support column 20B via the connecting portion 21A. The connecting portion 21A allows the arm 21 to move in the height direction with respect to the support column 20B. Further, the arm 21 can rotate around a rotation axis perpendicular to the support column 20B, penetrating the connection portion 21A.

The arm 21 is composed of a radiation source accommodating portion 22, a photographing table 23, and a main body portion 24. The radiation source 25 is accommodated in the radiation source accommodating portion 22. Breast M is placed on the imaging table 23. The radiation detector 26 is housed in the photographing table 23. The main body portion 24 integrally connects the radiation source accommodating portion 22 and the photographing table 23. The main body portion 24 holds the radiation source accommodating portion 22 and the photographing table 23 at positions facing each other. Handrails 27 on both sides of the main body 24 are provided so that the hand of the subject H can be grasped.

The radiation source 25 includes a radiation tube 29 and a housing 30 that houses the radiation tube 29. The inside of the housing 30 is filled with insulating oil. The radiation tube 29 emits radiation R toward the breast M placed on the imaging table 23. The radiation detector 26 detects the radiation R transmitted through the breast M and outputs a radiation image RI.

An irradiation field limiting device 31 is provided between the radiation source accommodating portion 22 and the photographing table 23. The irradiation field limiting device 31 is also called a collimator, and defines the irradiation field of the radiation R to the photographing table 23.

A face guard 32 is attached to the radiation source accommodating portion 22. The face guard 32 is formed or coated with a material that does not transmit radiation R, and protects the face of the subject H from radiation R.

A compression plate 33 is attached between the shooting table 23 and the irradiation field limiting device 31. The compression plate 33 is made of a material that transmits radiation R. The compression plate 33 is arranged at a position facing the photographing table 23. The compression plate 33 can be moved in a direction toward the photographing table 23 and a direction away from the photographing table 23 according to the operation of the elevating switch (not shown). The compression plate 33 moves toward the imaging table 23, sandwiches the breast M with the imaging table 23, and presses the breast M.

An ultraviolet source 34 is provided on the outer surface of the irradiation field limiting device 31 facing the compression plate 33. More specifically, the ultraviolet source 34 is provided on the outer surface of the irradiation field limiting device 31 on the back side of the face guard 32. The ultraviolet source 34 may be provided inside the irradiation field limiting device 31.

As an example, as shown in FIG. 3, the ultraviolet source 34 emits ultraviolet UV toward the radiation detector 26. The ultraviolet UV emitted from the ultraviolet source 34 irradiates the face guard 32, the compression plate 33, and the like. Ultraviolet UV is, for example, deep ultraviolet having a center wavelength in the range of 200 nm or more and 280 nm or less.

As the ultraviolet source 34, an LED (Light Emitting Diode), an LD (Laser Diode), or the like can be used in addition to an ultraviolet lamp using a quartz tube. In this example, an excimer lamp, which is a kind of ultraviolet lamp, is used as the ultraviolet source 34.

The face guard 32 and the compression plate 33 are made of a material that transmits ultraviolet rays and UV rays. Examples of the material that transmits ultraviolet rays and UV rays include the product name “Cytop (registered trademark)” manufactured by AGC Inc. Therefore, the ultraviolet UV rays enter the face guard 32 from the back surface of the face guard 32 and irradiate the surface of the face guard 32 facing the face of the subject H. Further, the ultraviolet UV rays enter the compression plate 33 from the back surface of the compression plate 33 and irradiate the surface of the compression plate 33 in contact with the breast M. Further, the ultraviolet UV transmitted through the compression plate 33 irradiates the imaging table 23 on which the breast M is placed. That is, in this example, ultraviolet UV rays are mainly applied to the photographing table 23, the face guard 32, and the compression plate 33.

The photographing table 23, the face guard 32, and the compression plate 33 are sterilized by being irradiated with ultraviolet rays UV. Here, "sterilization" by ultraviolet UV means that bacteria, microorganisms, or viruses adhering to the irradiated object are made inactive by light energy. The UV UV irradiation time required for sterilization varies depending on the UV UV irradiation energy, the distance from the UV source 34 to the UV UV irradiation site, the type of bacteria or virus to be sterilized, and the like, but it varies from several minutes to several tens. It's about a minute. For example, it has been reported that the new coronavirus is inactivated by irradiation with ultraviolet rays for several minutes.

A power supply device 40 for supplying electric power to each part in the device main body 11 is provided in the support column 20B. A voltage cable (not shown) extending from the power supply device 40 is arranged in the support column 20B. The voltage cable is further introduced from the connection portion 21A through the arm 21 into the radiation source accommodating portion 22, and is connected to the radiation tube 29, the radiation detector 26, the ultraviolet source 34, and the like. The power supply device 40 supplies power to the radiation tube 29, the radiation detector 26, and the ultraviolet source 34, respectively, via a voltage cable.

A power cable 40A is connected to the power supply device 40. One end of the power cable 40A is connected to the power supply device 40, and the other end extends to the outside of the device main body 11. The other end of the power cable 40A is connected to an external power source 70 (see FIG. 5). AC power is supplied to the power supply device 40 from the external power source 70 via the power cable 40A. The power supply device 40 has a converter circuit that converts alternating current into direct current, a voltage stabilizing circuit that stabilizes the voltage value, and the like. It is an AC power supply for formulas, etc.

The radiation tube 29 generates radiation based on the electric power supplied from the electric power supply device 40. The radiation detector 26 performs a radiation detection operation based on the electric power supplied from the electric power supply device 40. The ultraviolet source 34 generates ultraviolet rays based on the electric power supplied from the electric power supply device 40.

As shown in FIG. 4, as an example, the computer constituting the control device 12 has a storage 50, a memory 51, a CPU (Central Processing Unit) 52, a display 53, and an input device 54.

The storage 50 is a storage device such as a hard disk drive built in the computer constituting the control device 12 or connected via a cable or a network. The storage 50 stores control programs such as an operating system, various application programs, and various data associated with these programs.

The memory 51 is a work memory for the CPU 52 to execute a process. The CPU 52 comprehensively controls each part of the computer by loading the program stored in the storage 50 into the memory 51 and executing the processing according to the program.

The display 53 displays various screens. Operation functions by GUI (Graphical User Interface) are realized on various screens. The computer constituting the control device 12 receives input of an operation instruction from the input device 54 through various screens. The input device 54 is a keyboard, a mouse, a touch panel, or the like.

The operation program 55 is stored in the storage 50. The operation program 55 is an application program for operating the computer as the control device 12. In addition to the operation program 55, the storage 50 stores the irradiation condition table 56, the irradiation condition information 57 for each order, and the like.

The CPU 57 of the control device 12 performs processing in cooperation with the memory 51 and the like based on the operation program 55, so that the reception unit 60, the read / write (RW: Read Write) control unit 61, the main control unit 62, and the image processing are performed. It functions as a unit 63 and a display control unit 64.

The reception unit 60 receives various operation instructions input by the operator via the input device 54. For example, the reception unit 60 receives the shooting menu 65. The reception unit 60 outputs the shooting menu 65 to the RW control unit 61.

The RW control unit 61 receives the shooting menu 65 from the reception unit 60. The RW control unit 61 reads out the irradiation condition 66 corresponding to the received photographing menu 65 from the irradiation condition table 56. The RW control unit 61 writes the irradiation condition 66 read from the irradiation condition table 56 in the irradiation condition information 57 for each order.

The main control unit 62 controls the power supply device 40 and the radiation detector 26. The radiation source 25 and the ultraviolet source 34 are controlled by the main control unit 62 via the power supply device 40. The main control unit 62 reads out the irradiation condition 66 from the irradiation condition information 57 for each order. The main control unit 62 operates the radiation tube 29 by controlling the power supply device 40 according to the irradiation condition 66, and emits radiation R from the radiation tube 29 toward the radiation detector 26. The main control unit 62 outputs the radiation image RI detected by the radiation detector 26 by the irradiation of the radiation R from the radiation detector 26 to the image processing unit 63.

The image processing unit 63 receives the radiation image RI from the radiation detector 26. The image processing unit 63 performs various image processing on the radiation image RI. The image processing unit 63 outputs the radiographic image RI after image processing to the display control unit 64. The display control unit 64 receives the radiographic image RI from the image processing unit 63. The display control unit 64 displays the radiographic image RI on the display 53.

Further, the control device 12 executes an automatic calibration operation. In the automatic calibration operation, the control device 12 acquires an offset image by reading a signal from the radiation detector 26 in a state where the radiation R is not irradiated to the radiation detector 26, and stores the acquired offset image in the memory 51. do. The image processing unit 63 reads an offset image from the memory 51 at the time of radiography, and performs offset correction by subtracting the offset image from the radiographic image RI detected by the radiation detector 26.

The automatic calibration operation is periodically performed at the time of starting the device main body 11 or every time a certain period of time elapses. The irradiation of ultraviolet UV rays from the ultraviolet source 34 to the photographing table 23 may be performed during the automatic calibration operation.

As an example, as shown in FIG. 5, the power supply device 40 includes a first power supply unit 41, a second power supply unit 42, a third power supply unit 43, and an isolation transformer 44. The first power supply unit 41 converts the AC voltage supplied from the external power source 70 via the isolation transformer 44 into a DC voltage and supplies it to the radiation detector 26. The second power supply unit 42 converts the AC voltage supplied from the external power source 70 via the isolation transformer 44 into a DC voltage and supplies it to the ultraviolet source 34. The third power supply unit 43 converts the AC voltage supplied from the external power source 70 via the isolation transformer 44 into a DC voltage and supplies it to the radiation tube 29 included in the radiation source 25.

The isolation transformer 44 is a transformer having a function of preventing an abnormal current or the like from flowing into the power supply device 40 from the external power supply 70. The isolation transformer 44 is composed of a primary side coil 45 connected to the external power supply 70 and three secondary side coils 46A, 46B, 46C individually provided for the primary side coil 45. The primary coil 45 and the three

secondary coils

46A, 46B, 46C are electrically separated from each other. Further, the three

secondary coil

46A, 46B, and 46C are electrically separated from each other. In addition, "electrically separated" means that they are electrically isolated from each other. The isolation transformer 44 is an example of a "transformer" according to the technique of the present disclosure.

The first power supply unit 41 is connected to the secondary coil 46A. The second power supply unit 42 is connected to the secondary coil 46B. The third power supply unit 43 is connected to the secondary coil 46C. The first power supply unit 41, the second power supply unit 42, and the third power supply unit 43 are provided with

reference electrodes

41A, 42A, and 43A for applying a reference potential, respectively.

The reference electrode 41A of the first power supply unit 41 and the reference electrode 43A of the third power supply unit 43 are connected to, for example, a metal constituting the housing of the apparatus main body 11 (hereinafter, referred to as housing metal). As a result, a ground potential is applied. The housing metal is a metal for determining a reference potential in the apparatus main body 11.

On the other hand, the reference electrode 42A of the second power supply unit 42 is not connected to the housing metal. In the present embodiment, the reference electrode 42A of the second power supply unit 42 is not connected to any metal and is in a floating state. The reference electrode 42A may be connected to another metal electrically separated from the housing metal to which the

reference electrodes

41A and 43A are connected.

In this way, the second power supply unit 42 is electrically separated from the first power supply unit 41. Further, the second power supply unit 42 is electrically separated from the third power supply unit 43. Therefore, it is possible to prevent the electrical noise generated in the first power supply unit 41 or the third power supply unit 43 from being transmitted to the second power supply unit 42. As a result, the second power supply unit 42 can supply stable power to the radiation detector 26.

The first power supply unit 41 is, for example, a power supply circuit including a converter circuit 71. The converter circuit 71 generates a DC voltage having various voltage values based on the AC voltage supplied from the external power supply 70 via the primary side coil 45 and the secondary side coil 46A, and inputs the DC voltage to the radiation detector 26. ..

The second power supply unit 42 is, for example, a power supply circuit including a converter circuit 72 and an inverter circuit 73. The converter circuit 72 generates a DC voltage based on the AC voltage supplied from the external power supply 70 via the primary side coil 45 and the secondary side coil 46B, and supplies the generated DC voltage to the inverter circuit 73. The inverter circuit 73 generates a pulse-shaped drive voltage with pulse width modulation based on the supplied DC voltage, and inputs the generated drive voltage to the ultraviolet source 34.

The third power supply unit 43 has, for example, a converter circuit 74 and a high voltage generation circuit 75. The converter circuit 74 generates a DC voltage based on the AC voltage supplied from the external power supply 70 via the primary side coil 45 and the secondary side coil 46C, and supplies the generated DC voltage to the high voltage generation circuit 75. The high voltage generation circuit 75 generates a high voltage pulse based on the supplied DC voltage, and applies the generated high voltage pulse to the radiation tube 29.

The operation of the inverter circuit 73 and the high voltage generation circuit 75 is controlled by the main control unit 62. The main control unit 62 controls the irradiation energy of the ultraviolet UV generated by the ultraviolet source 34 by controlling the duty ratio of the pulsed drive voltage generated by the inverter circuit 73. Further, the main control unit 62 controls the irradiation time of ultraviolet UV by controlling the operation of the inverter circuit 73.

Further, the main control unit 62 controls the timing at which the high voltage generation circuit 75 generates a high voltage pulse. Further, the main control unit 62 controls the radiation detection operation by the radiation detector 26.

As an example, as shown in FIG. 6, the radiation detector 26 has a sensor board 80, a drive unit 81, a signal processing unit 82, and a sensor control unit 83. The radiation detector 26 of the present embodiment is an indirect conversion type radiation detector that converts radiation into light and then converts light into electric charges.

A scintillator 84 as a conversion layer is laminated on the sensor substrate 80. The scintillator 84 is formed of, for example, GOS (Gd ₂ O ₂ : Tb) or CsI (CsI: TI). The scintillator 84 converts the radiation R emitted from the radiation source 25 and transmitted through the breast M (see FIG. 2) into light.

On the sensor substrate 80, photodiodes 85 as photoelectric conversion elements are arranged in a two-dimensional matrix. The photodiode 85 generates an electric charge according to the light converted by the scintillator 84, and accumulates the generated electric charge.

A TFT (Thin Film Transistor) 86 as a switch element is connected to the cathode side of the photodiode 85. The photodiode 85 is connected to the source electrode of the TFT 85. The drain electrode of the TFT 86 is connected to the signal line 87. The gate electrode of the TFT 86 is connected to the scanning line 88.

The anode side of the photodiode 85 is connected to the bias wire 89. A reverse bias voltage is applied to the bias line 89 from the first power supply unit 41.

A plurality of scanning lines 88 are connected to the drive unit 81. The drive unit 81 is, for example, a gate driver. The drive unit 81 is supplied with an on voltage and an off voltage from the first power supply unit 41. The drive unit 81 switches the voltage applied to the scanning line 88 between the on voltage and the off voltage based on the timing signal supplied from the sensor control unit 83. That is, the drive unit 81 inputs a drive signal for outputting electric charges from each of the plurality of pixels to the sensor board 80. The pixel is composed of a photodiode 85 and a TFT 86.

The TFT 86 is turned on when an on-voltage is applied via the scanning line 88, and conducts the photodiode 85 and the signal line 87. When the photodiode 85 and the signal line 87 are electrically connected, an electric signal corresponding to the electric charge stored in the photodiode 85 is output to the signal line 87. The electric signal output to the signal line 87 is input to the signal processing unit 82.

The signal processing unit 82 generates image data corresponding to the electrical signals input from each of the signal lines 87, and outputs the image data as a radiographic image RI. The signal processing unit 82 is a signal processing circuit including an amplifier circuit, a correlated double sampling circuit, a multiplexer, an A / D converter, and the like. An amplifier circuit and a correlated double sampling circuit are provided for each signal line 87.

The sensor control unit 83 controls the operations of the drive unit 81 and the signal processing unit 82. The sensor control unit 83 is composed of, for example, a CPU, an FPGA (Field Programmable Gate Array), or the like. Power is supplied to the sensor control unit 83 and the signal processing unit 82 from the first power supply unit 41. The sensor control unit 83 is an example of a “control unit” according to the technique of the present disclosure.

The drive unit 81 is formed on the drive board, and the signal processing unit 82 is formed on the signal processing board. The first power supply unit 41 supplies power to the drive board and the signal processing board. A part of the circuit constituting the drive unit 81 may be formed on the drive board. Further, the signal processing board may be configured with a part of the circuit constituting the signal processing unit 82.

In the present embodiment, the radiation detector 26 is an indirect conversion type, but a direct conversion type may be used. In the direct conversion type radiation detector, a conversion layer such as amorphous selenium (a-Se) that directly converts radiation into electric charge is used. Further, in the direct conversion type radiation detector, a capacitor for accumulating the electric charge generated by the conversion layer is provided instead of the photodiode 85. In the direct conversion type radiation detector, a bias voltage is applied to the conversion layer from the first power supply unit 41 in the power supply device 40. That is, in the direct conversion type, the first power supply unit 41 that supplies the bias voltage to the conversion layer is electrically separated from the second power supply unit 42 that supplies the voltage to the ultraviolet source. Other configurations are the same as those of the indirect conversion type radiation detector 26. That is, the radiation detector 26 may have a plurality of pixels that generate and accumulate charges according to the incident amount of the radiation R.

As an example, as shown in FIG. 7, the ultraviolet source 34 is an excimer lamp composed of a discharge container 90, an external electrode 91, and an internal electrode 92. The discharge container 90 is a double quartz tube having a discharge space 93 formed inside. The discharge space 93 is filled with, for example, xenon and chlorine as a discharge gas. The external electrode 91 is formed of, for example, a metal net that transmits light.

A pulsed drive voltage is applied from the second power supply unit 42 between the external electrode 91 and the internal electrode 92. By applying a driving voltage between the external electrode 91 and the internal electrode 92, the discharge gas in the discharge space 93 is excited, and then ultraviolet UV is generated when the excimer state is reached and the ground state is returned.

The ultraviolet source 34 may be an LED that emits deep ultraviolet rays. When the ultraviolet source 34 is an LED, the second power supply unit 42 generates ultraviolet UV by supplying a pulsed drive current to the ultraviolet source 34. That is, the LED is driven by the pulse width modulation method.

As an example, as shown in FIG. 8, the radiation tube 29 has a cathode 101 and an anode 102 housed in a vacuum glass tube 100 having a substantially cylindrical shape. The cathode 101 emits electrons. The anode 102 emits radiation R when electrons collide with each other. The cathode 101 is a cold cathode. More specifically, the cathode 101 emits an electron beam EB toward the anode 102 by utilizing the field emission phenomenon. The anode 102 is a rotating anode that is rotated by a rotating mechanism. A fixed fixed anode may be used as the anode 102.

A high voltage pulse as a tube voltage is applied from the third power supply unit 43 between the cathode 101 and the anode 102. In response to the application of the high voltage pulse, the electron beam EB is emitted from the cathode 101 toward the anode 102. Then, at the anode 102, the radiation R is generated from the focal point F where the electron beam EB collides. Radiation R is emitted to the outside through an irradiation window 103 provided in the glass tube 100.

In the mammography apparatus 10 configured as described above, the radiation R emission by the radiation source 25 and the radiation detection by the radiation detector 26 are, for example, operation signals generated by the operator operating the input device 54. It is executed in conjunction. The emission of ultraviolet UV rays by the ultraviolet source 34 may be executed in conjunction with an operation signal generated by the operator operating the input device 54, or may be executed periodically regardless of the operation signal. good. Therefore, the operating period of the radiation detector 26 and the operating period of the ultraviolet source 34 may overlap.

It is assumed that the noise generated in the second power supply unit 42 that supplies power to the ultraviolet source 34 is transmitted to the first power supply unit 41 that supplies power to the radiation detector 26. In this case, even if the noise is minute, the radiation image RI detected by the radiation detector 26 may be affected. This is because the radiation detector 26 has a very high detection sensitivity. However, in the technique of the present disclosure, since the second power supply unit 42 is electrically separated from the first power supply unit 41, the influence of noise from the first power supply unit 41 to the radiation detector 26 is reduced. can do. Similarly, since the second power supply unit 42 is electrically separated from the third power supply unit 43, the influence of noise from the first power supply unit 41 to the radiation detector 26 can be reduced.

Further, the ultraviolet source 34 may operate while the radiation detector 26 is performing the calibration operation. In this case, if noise is transmitted from the first power supply unit 41 to the second power supply unit 42, the noise affects the offset image obtained from the radiation detector 26. As a result, noise affects the radiation image RI after offset correction. In the technique of the present disclosure, since the second power supply unit 42 is electrically separated from the first power supply unit 41, it is possible to reduce the influence of noise on the offset image due to the operation of the ultraviolet source 34.

In the above embodiment, the ultraviolet UV emitted by the ultraviolet source 34 is deep ultraviolet having a central wavelength in the range of 200 nm or more and 280 nm or less. The ultraviolet UV is particularly preferably deep ultraviolet having a center wavelength of 222 nm. Deep ultraviolet rays with a central wavelength of 222 nm have little effect on the human body. This is known, for example, in Japanese Patent No. 6306097. Since deep ultraviolet rays having a central wavelength of 222 nm have a small effect on the human body, it is possible to irradiate the subject with ultraviolet UV rays during radiography of the subject. The technique of the present disclosure is useful in a radiological diagnostic apparatus configured to perform ultraviolet irradiation during radiography.

In the above embodiment, the technique of the present disclosure has been described by taking a mammography apparatus as an example as a radiological diagnostic apparatus. The technique of the present disclosure is applied to a radiography apparatus having a standing or recumbent imaging table, a mobile radiography apparatus, a radioscopy imaging apparatus, a mobile radioscopy imaging apparatus, or a radiation tomography apparatus, in addition to the mammography apparatus. Is also applicable.

FIG. 9 shows an example of a radiological imaging apparatus having an imaging table. The radiation photographing apparatus 10A shown in FIG. 9 includes a radiation source 25, an irradiation field limiting device 31, a radiation detector 26, an ultraviolet source 34, a power supply device 40, a lying position photographing table 110, and a standing position photographing table 120. In this example, the radiation detector 26 is a portable so-called electronic cassette.

The recumbent position photographing table 110 is used when the subject H is photographed in the recumbent position. The standing image pickup table 120 is used when the subject H is photographed in a standing position. In the radiation detector 26, the radiation detector 26 is detachably set in the folder 111 of the recumbent position photographing table 110 or the folder 121 of the standing position photographing table 120.

The radiation source 25 is movable and is arranged at a position facing the radiation detector 26. FIG. 9 shows a state in which the radiation source 25 is arranged at a position facing the radiation detector 26 set in the folder 111 of the recumbent imaging table 110.

The ultraviolet source 34 is attached to, for example, the outer surface of the irradiation field limiting device 31 so as to irradiate the lying-position imaging table 110 or the standing-position imaging table 120 on which the subject H is arranged with ultraviolet UV rays.

The power supply device 40 supplies power to the radiation source 25, the ultraviolet source 34, and the radiation detector 26, respectively, as in the first embodiment.

The radiological imaging device 10A may be provided with at least one of the recumbent imaging table 110 and the standing imaging table 120.

FIG. 10 shows an example of a mobile radiation device. The mobile radiation device 10B shown in FIG. 10 is a so-called X-ray round-trip vehicle configured to be movable. The mobile radiation device 10B includes a trolley 130, a radiation source 25, an irradiation field limiting device 31, a radiation detector 26, an ultraviolet source 34, and a power supply device 40.

The dolly 130 is provided with a plurality of wheels 131 for moving the dolly 130. Further, the dolly 130 is provided with a handle 132 for the operator to push or pull the dolly 130 to move the dolly 130. Further, the dolly 130 is provided with an operation panel 133 for the operator to perform various operations.

Further, the trolley 130 has a built-in power supply device 40. The dolly 130 is connected to an external power source, and power is supplied to the power supply device 40 from the external power source (not shown). Further, the dolly 130 has a built-in battery (not shown), and power is supplied from the battery to the power supply device 40 as needed.

In addition, a support 134 is erected at the front of the bogie 130. The column 134 is rotatable about the vertical direction. An arm 135 is attached to the support column 134 so as to be movable in the vertical direction. The radiation source 25 is attached to the end of the arm 135.

In this example, the radiation detector 26 is a portable so-called electronic cassette. For example, the radiation detector 26 is arranged on the bed 136. The subject H is placed in a recumbent position on the bed 136 so that the radiation detector 26 is located at the imaging site. The radiation source 25 is movable by rotating the support column 134 and / or moving the arm 135 up and down, and is arranged at a position facing the radiation detector 26.

The ultraviolet source 34 is attached to, for example, the outer surface of the irradiation field limiting device 31 so as to irradiate the bed 136 on which the subject H is arranged with ultraviolet UV.

Further, the trolley 130 is provided with a folder 137 for storing the radiation detector 26 when not in use. The radiation detector 26 is charged, for example, in the folder 137. The ultraviolet source 34 may be provided in the folder 137 so as to irradiate the radiation detector 26 housed in the folder 137 with ultraviolet UV. Further, the ultraviolet source 34 may be provided on the support column 134, the arm 135, the carriage 130, or the like.

FIG. 11 shows an example of a radioscopic fluoroscopy apparatus. The radioscopic fluoroscopy apparatus 10C shown in FIG. 11 is a mobile radioscopic fluoroscopy apparatus configured to be movable. Further, FIG. 11 shows a C-arm type digital fluoroscopy apparatus as an example of the radioscopic fluoroscopy apparatus 10C. The fluoroscopy apparatus 10C includes a carriage 140, a radiation source 25, an irradiation field limiting device 31, a radiation detector 26, an ultraviolet source 34, and a power supply device 40.

The dolly 140 is provided with a plurality of wheels 141 for moving the dolly 140. Further, the C arm 143 is connected to the carriage 140 via the support portion 142. The support portion 142 rotatably supports the C arm 143. A radiation source 25 is provided at one end of the C arm 143, and a radiation detector 26 is provided at the other end. The radiation detector 26 is arranged at a position facing the radiation source 25.

Further, the trolley 140 has a built-in power supply device 40. The dolly 140 is connected to an external power source, and power is supplied to the power supply device 40 from the external power source (not shown). Further, the dolly 140 has a built-in battery (not shown), and power is supplied from the battery to the power supply device 40 as needed.

In the example shown in FIG. 11, the ultraviolet source 34 is attached to the outer surface of the irradiation field limiting device 31 and emits ultraviolet UV toward the radiation detector 26. As a result, the radiation detector 26 is sterilized. Further, in this example, when the radiation source 25 is placed above the subject (not shown) and radioscopic radiography (so-called overtube radioscopic radiography) is performed, the subject and the subject are subjected to radiation fluoroscopy. The bed (not shown) to be placed can be sterilized.

FIG. 12 illustrates a state in which the subject H is subjected to radioscopic fluoroscopy by the undertube method using the radioscopic fluoroscopy apparatus 10C. Subject H is placed on the bed 144. In the undertube method, the position of the C arm 143 is adjusted so that the radiation source 25 is located below the bed 144 and the radiation detector 26 is located above the bed 144. The radiation detector 26 images the radiation transmitted through the bed 144 and the subject H.

In the example shown in FIG. 12, the ultraviolet source 34 is attached to the C arm 143 and is directed from above the subject H toward the bed 144 arranged between the radiation source 25 and the radiation detector 26. Ultraviolet UV is emitted. As a result, the bed 144 and the subject H are sterilized.

The ultraviolet source 34 is not limited to the irradiation field limiting device 31 or the C arm 143, and may be attached to the radiation detector 26, the trolley 140, or the like.

The fluoroscopy apparatus shown in FIGS. 11 and 12 is a mobile type, but the fluoroscopy apparatus may be a stationary type.

FIG. 13 shows an example of a radiation tomography apparatus. The radiation tomography apparatus 10D shown in FIG. 13 is a so-called CT (Computed Tomography) apparatus. The radiation tomography apparatus 10D includes a gantry 150, an imaging table 151, a radiation source 25, an irradiation field limiting device 31, a radiation detector 26, an ultraviolet source 34, and a power supply device 40.

The gantry 150 has a gantry rotating portion 152. The gantry rotating portion 152 has a cavity portion 153 and is rotatably supported by the gantry 150. The subject (not shown) placed on the photographing table 151 is conveyed to the cavity 153.

The gantry rotating unit 152 has a built-in radiation source 25, an irradiation field limiting device 31, and a radiation detector 26. The radiation source 25 and the radiation detector 26 are arranged at positions facing each other with the cavity 153 interposed therebetween. The radiation source 25, the irradiation field limiter 31, and the radiation detector 26 rotate with the rotation of the gantry rotating unit 152. A tomographic image is generated by reconstructing a plurality of images output from the radiation detector 26.

The ultraviolet source 34 is provided in the gantry rotating portion 152, and irradiates the hollow portion 153 with ultraviolet UV. Therefore, a part of the photographing table 151 inserted in the cavity portion 153 and a part of the subject H are irradiated with ultraviolet UV rays. In this example, the ultraviolet source 34 rotates with the rotation of the gantry rotating portion 152. The ultraviolet source 34 may be provided at a location other than the gantry rotating portion 152 of the gantry 150, or at a photographing table 151 or the like.

The mammography apparatus 10 described in the above embodiment may have a tomosynthesis function capable of acquiring a tomographic image. In the mammography apparatus 10 having a tomosynthesis function, pre-imaging at a low dose is performed in order to determine the irradiation conditions of radiation in tomosynthesis imaging. At the time of this pre-shooting, the ultraviolet UV may be irradiated by the ultraviolet source 34. According to the technique of the present disclosure, since the first power supply unit 41 and the second power supply unit 42 are electrically separated, the noise generated in the second power supply unit 42 when irradiated with ultraviolet UV rays is the first. 1 It is prevented from being transmitted to the power supply unit 41. This reduces the influence of noise on the pre-shooting image obtained by pre-shooting.

The techniques of the present disclosure can be appropriately combined with the various embodiments described above and / or various modifications. Further, it is of course not limited to each of the above embodiments, and various configurations can be adopted as long as they do not deviate from the gist.

The description and illustrations shown above are detailed explanations of the parts related to the technique of the present disclosure, and are merely an example of the technique of the present disclosure. For example, the description of the configuration, function, action, and effect described above is an example of the configuration, function, action, and effect of a portion of the art of the present disclosure. Therefore, unnecessary parts may be deleted, new elements may be added, or replacements may be made to the contents described above and the contents shown above within a range not deviating from the gist of the technique of the present disclosure. Needless to say. Further, in order to avoid confusion and facilitate understanding of the parts related to the technique of the present disclosure, the description contents and the illustrated contents shown above require special explanation in order to enable the implementation of the technique of the present disclosure. The explanation about the common technical knowledge that is not used is omitted.

In the present specification, "A and / or B" is synonymous with "at least one of A and B". That is, "A and / or B" means that it may be only A, it may be only B, or it may be a combination of A and B. Further, in the present specification, when three or more matters are connected and expressed by "and / or", the same concept as "A and / or B" is applied.

All documents, patent applications and technical standards described herein are to the same extent as if it were specifically and individually stated that the individual documents, patent applications and technical standards are incorporated by reference. Incorporated by reference in the book.

Claims

A radiation detector that detects radiation and
An ultraviolet source that emits ultraviolet rays and
The first power supply unit that supplies power to the radiation detector,
A second power supply unit that is electrically separated from the first power supply unit and supplies power to the ultraviolet source,
A radiation diagnostic device equipped with.
The ultraviolet rays are deep ultraviolet rays having a central wavelength in the range of 200 nm or more and 280 nm or less.
The radiation diagnostic apparatus according to claim 1.
The ultraviolet source emits the ultraviolet rays toward the radiation detector.
The radiation diagnostic apparatus according to claim 1 or 2.
The radiation detector is
A sensor board on which multiple pixels are formed to generate and accumulate electric charges according to the amount of radiation incident,
A drive unit that inputs a drive signal for outputting electric charges from each of the plurality of pixels to the sensor board, and a drive unit.
An electric signal corresponding to the electric charge output from the sensor board is input, and a signal processing unit that generates and outputs image data based on the input electric signal, and a signal processing unit.
It has the sensor board, the drive unit, and a control unit that controls the signal processing unit.
The radiation diagnostic apparatus according to claim 3.
The sensor substrate has a conversion layer that directly converts radiation into electric charges.
The first power supply unit supplies a bias voltage to the conversion layer.
The radiation diagnostic apparatus according to claim 4.
The ultraviolet source is an excimer lamp.
The radiation diagnostic apparatus according to any one of claims 1 to 5.
The second power supply unit includes an inverter circuit.
The radiation diagnostic apparatus according to claim 6.
The ultraviolet source is an LED.
The radiation diagnostic apparatus according to any one of claims 1 to 5.
A pulsed drive current is supplied from the second power supply unit.
The radiation diagnostic apparatus according to claim 8.
The first power supply unit and / or the second power supply unit is a power supply circuit including a converter circuit that converts an AC voltage into a DC voltage.
The radiation diagnostic apparatus according to any one of claims 1 to 9.
The first power supply unit and the second power supply unit are electrically separated by a transformer having a secondary coil separately provided for the primary coil.
The radiation diagnostic apparatus according to any one of claims 1 to 10.
The reference electrode of the first power supply unit and the reference electrode of the second power supply unit are electrically separated.
The radiation diagnostic apparatus according to any one of claims 1 to 11.
A radiation source that emits radiation toward the radiation detector,
A third power supply unit that is electrically separated from the first power supply unit and the second power supply unit and that supplies power to the radiation source.
The radiological diagnostic apparatus according to any one of claims 1 to 12, further comprising.
The radiodiagnosis device is any one of a radiography device having a standing or lying position radiography table, a mammography device, a radioscopic fluoroscopy device, a mobile radiography device, a mobile radioscopic fluoroscopy device, and a radiotomography device. Is it,
The radiation diagnostic apparatus according to claim 13.