KR20090013130A - Radiation detecting cassette and medical system - Google Patents

Abstract

A radiation detecting cassette and a medical system are provided to improve reliability of a medical system and communications of a radiation detecting cassette by improving transmission of image data. A radiation conversion panel is loaded in a casing, detects a radiation(X) transmitting a subject(14), and converts a detected radiation into radiation image information. A memory is loaded in the casing, and memorizes the radiation image information converted by the radiation conversion panel. A communications unit is loaded in the casing, and transmits the radiation image information to an external device. A controller is loaded in the casing. A communications maintaining unit is loaded in the casing, and maintains transmitted radiation image information while the communications unit transmits the radiation image information.

Description

Radiation Detection Cassette and Medical System {RADIATION DETECTING CASSETTE AND MEDICAL SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical system including a radiation detection cassette containing a radiation conversion panel for detecting radiation that has passed through a subject and converting the detected radiation into radiation image information.

BACKGROUND OF THE INVENTION In the medical field, a radiographic imaging apparatus for irradiating a subject to radiation and guiding radiation transmitted through the subject to a radiation conversion panel to photograph a radiographic image from the radiation has been widely used. The known configuration of the radiation conversion panel is a conventional radiation film for recording a radiation image by exposure, and a accumulator for accumulating radiation energy representing a radiation image on a phosphor and regenerating the radiation image as excitation light by irradiating excitation light to the phosphor. Phosphor panels.

A radiation film on which a radiographic image is recorded is supplied to a developing apparatus to develop a radiographic image, or an accumulator phosphor panel is supplied to a reading apparatus to read the radiographic image as a visible image.

In an operating room or the like, it is necessary to read the recorded radiographic image immediately from the radiation conversion panel after the radiographic image is taken to quickly and accurately treat the patient. As such a radiation converting panel, a radiation detector having a solid state element detector which converts radiation directly into an electrical signal or converts radiation into visible light by a scintillator, and then converts visible light into an electrical signal and reads the detected radiation image. Is being developed.

In the radiographic imaging system provided with the radiation conversion panel, the radiographic image information detected by the radiation conversion panel is transmitted to the host computer. Techniques related to such a radiographic imaging system are disclosed in, for example, Japanese Patent Laid-Open No. 2003-172783, Japanese Patent Laid-Open No. 2004-141240, and Japanese Patent Laid-Open No. 2005-006979.

According to the technique disclosed in Japanese Patent Laid-Open No. 2003-172783, image data detected by a radiation detection cassette containing a radiation detector is converted into a radio signal and transmitted to an external signal receiver by image data transmission means. Therefore, the radiation detection cassette is independent of the controller without requiring wiring, and it is possible to take an image from a position away from the controller, and can be conveniently used. Image data can also be transmitted by a cable that can be used to supply power.

According to the technique disclosed in Japanese Patent Laid-Open No. 2004-141240, the radiation detection cassette receives order information instructing to photograph a radiographic image from an external device, stores the received order information, stores the stored order information and the radiation solids. The image signal output from the detector is transmitted to the external device. The disclosed radiation detection cassette can greatly reduce the burden placed on the radiographer who takes a radiographic image using the radiation detection cassette.

According to the technique disclosed in Japanese Patent Laid-Open No. 2005-006969, the radiographic imaging apparatus includes a wired communication unit that transmits and receives digital image data and image capture control signals to and from an external circuit through a cable, and wirelessly transmits digital signals and image capture control signals. It includes a wireless communication unit for transmitting and receiving with an external circuit. By simply detaching the cable, other data communication systems and power supply methods can optionally be used to emphasize high data transfer rates or easy handling of the radiographic imaging apparatus.

Conventional medical systems equipped with a radiation detection cassette containing a radiation detector do not have any means for displaying or maintaining the state of transmission of image data. Since conventional medical systems do not give the user any instructions, such as whether the transmission of image data from the radiation detector to the host computer is in progress or has ended, the user accidentally removes the battery from the radiation detection cassette or the operator of the host computer The following processing can be started while the image data is being transmitted. Therefore, the storage of image data to the host computer may be hindered or the reliability may be lowered.

It is an object of the present invention to provide a reliable transmission of image data to a host computer, including means for displaying or maintaining the state of transmission of image data, thereby making the radiation detection cassette more reliable with respect to communication and more reliable when operating a medical system. To provide a radiation detection cassette and medical system.

According to the first aspect of the present invention, there is provided a casing, a radiation conversion panel that detects radiation transmitted to the casing through the subject and converts the detected radiation into radiographic image information, and a radiation image accommodated in the casing and converted by the radiation conversion panel. A memory for storing information, a communication unit housed in the casing to transmit at least the radiographic image information to an external device, a controller housed in the casing, and a housing housed in the casing and at least the communication unit transmits the radiographic image information. It is to provide a radiation detection cassette including a communication holding unit for holding the received radiographic image information.

According to the second aspect of the present invention, there is provided a radiation detection cassette including a casing, a radiation conversion panel that detects radiation that is received in the casing and passes through the subject, and converts the detected radiation into radiographic image information; A radiation detection cassette including a memory for storing the radiographic image information converted by the apparatus, a communication unit housed in the casing to transmit at least the radiographic image information to an external device, and a cassette controller housed in the casing; An image photographing apparatus for irradiating a subject with radiation; A host computer for exchanging information with the radiation detection cassette to control the image photographing apparatus; And a display device for displaying information from the host computer; The cassette controller includes a capacitance value transmitter for transmitting the capacitance value of the radiation image information to the host computer before the radiation image information is transmitted, and an image information transmitter for transmitting the radiation image information; The host computer controls the display device to display an indicator indicating the capacitive value received from the radiation detection cassette as an upper limit, and the display computer controls the display device to move toward the displayed indicator during the period in which the radiographic image information is being received and the radiation image. A medical system comprising a bar image controller for displaying a bar image to have a length corresponding to a reception capacity value of information.

The radiation detection cassette and medical system according to the present invention can reliably transmit image data to a host computer, thereby increasing the reliability of communication of the radiation detection cassette and the reliability of the medical system.

These and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which preferred embodiments of the present invention are shown as illustrative examples.

Hereinafter, the radiation detection cassette and medical system according to the present invention will be described with reference to FIGS. 1 to 17 as applied to a radiographic imaging system.

1 shows, in perspective view, an operating room 12 in which a radiographic imaging system 10 (also referred to hereinafter as an "imaging imaging system 10") is installed.

As shown in FIG. 1, the operating room 12 is in addition to the imaging device system 10 by an operating table 16 that lays the patient 14 thereon and a doctor 18 operating the patient 14. It has an instrument stand 20 arranged on one side of the operating table 16 for positioning the various tools and instruments used. The operating table 16 is arranged with a variety of devices required for surgery, including anesthesia device, aspirator, electrocardiograph, blood pressure monitor and the like.

The image capturing system 10 will be described later, which detects an image capturing apparatus 22 that irradiates the patient 14 with the radiation X at an irradiation amount under an image capturing condition, and which detects the radiation X that has passed through the patient 14. A radiation detecting cassette 24 (hereinafter referred to as " cassette 24 ") for receiving a radiation detector, and a display device 26 for displaying a radiographic image based on the radiation X detected by the radiation detector; , A host computer 28 that controls the image photographing device 22, the cassette 24, and the display device 26. The image photographing device 22, the cassette 24, the display device 26, and the host computer 28 transmit and receive signals by wireless communication with each other. The host computer 28 includes a console 27 and a display 29.

The imaging device 22 is connected to the first material arm 30 so as to be movable to a desired position for taking an image at a desired portion of the patient 14 and the doctor 18 to perform surgery on the patient 14. You will be evacuated to an off-site location. Similarly, the display device 26 is connected to the second material arm 32 so that the photographed radiographic image displayed on the display device 26 can be moved to a position where the doctor 18 can easily confirm.

2 shows a detailed internal structure of the radiation detection cassette 24. As shown in FIG. 2, the radiation detection cassette 24 has a casing 34 made of a material that transmits radiation X. As shown in FIG. The casing 34 includes a grid 38 for removing scattered lines of radiation X from the patient 14, a radiation detector (radiation conversion panel) 40 for detecting radiation X transmitted through the patient 14, And a lead plate 42 that absorbs the white scattering lines from the radiation X. The grid 38, the radiation detector 40, and the lead plate 42 are continuously arranged in that order from the irradiation surface of the casing 34 to which the radiation X is irradiated. Irradiation surface 36 of casing 34 may be configured as grid 38.

In addition, the casing 34 is a battery pack 45 for accommodating the battery 44 as a power supply of the cassette 24, and a cassette controller 46 for driving the radiation detector 40 with power supplied from the battery 44. And a communication unit 48 that transmits and receives a signal including the information of the radiation X detected by the radiation detector 40 between the host computers 28. A shielding plate 42 such as lead under the irradiation surface 36 of the casing 34 protects the cassette controller 46 and the communication unit 48 to avoid damage caused by radiation X being radiated. The cassette controller 46 and the communication unit 48 are preferably arranged on the side.

3 shows a block diagram of the circuit arrangement of the radiation detector 40. As shown in FIG. 3, the radiation detector 40 is an array of thin film transistors (TFTs) arranged in rows and columns, a material such as amorphous selenium (a-Se) that generates an electric charge upon detection of radiation (X). And an array of storage capacitors 53 connected to the photoelectric conversion layer 51 and the photoelectric conversion layer 51 disposed on the array of the TFTs 52. When the radiation X is irradiated to the radiation detector 40, the photoelectric conversion layer 51 generates a charge, and the storage capacitor 53 stores the generated charge. At that time, the TFT 52 is sequentially turned on for each row to read charges from the storage capacitor 53 as image signals. In FIG. 3, one of the photoelectric conversion layer 51 and the storage capacity 53 is shown as the pixel 50, and the pixel 50 is connected to one of the TFTs 52. The details of the other pixels 50 are not shown. Since amorphous celen tends to change its structure and deteriorate its function at high temperatures, amorphous selenium needs to be used within a predetermined temperature range. Therefore, it is preferable that the radiation detection cassette 24 be provided with some means for cooling the radiation detector 40.

The TFT 52 connected to each pixel 50 is connected to each gate line 54 extending parallel to the row and each signal line 56 extending parallel to the column. Gate line 54 is connected to line scanning driver 58, and signal line 56 is connected to multiplexer 66, which serves as a readout circuit.

The control signal (Von _, Voff) for turning on and off the TFT 52 along the row is supplied to the gate line 54 from the line scanning driver 58. The line scanning driver 58 includes a plurality of first switches SW1 for switching the gate line 54 and a row address decoder 60 for outputting a selection signal for selecting one of the switches SW1 at one time. . The address signal is supplied from the cassette controller 46 to the row address decoder 60.

The signal line 56 is supplied with electric charges stored in the storage capacitor 53 of the pixel 50 via the TFTs 52 arranged in columns. The electric charge supplied to the signal line 56 is amplified by the amplifiers 62 respectively connected to the signal line 56. The amplifier 62 is connected to the multiplexer 66 via each sample hold circuit 64. The multiplexer 66 includes a plurality of second switches SW2 for continuously switching the signal lines 56 and a column address decoder 68 for outputting a selection signal for selecting one of the second switches SW2 at one time. Include. The column address decoder 68 is supplied with an address signal from the cassette controller 46. The multiplexer 66 has an output terminal connected to the A / D converter 70. The radiographic image signal generated by the multiplexer 66 based on the charge from the sample hold circuit 64 is converted by the A / D converter 70 into a digital image signal representing the radiographic image signal, which is then converted into the cassette controller 46. Supplied.

4 shows in a block diagram a radiographic imaging system including an image pickup device 22, a cassette 24, a display device 26, and a host computer 28. The host computer 28 is connected to a radiation information system (RIS) 146 which overall manages radiographic image information and other information handled by the radiation department of a hospital. The RIS 146 is connected to a hospital information system (HIS) 148 that manages medical information as a whole at the hospital.

The image capturing apparatus 22 receives an image capturing condition from the host computer 28 by an image capturing switch 74, a radiation source 76 that outputs radiation X, and wireless communication, and receives the host computer 28 by wireless communication. Radiation source 76 based on a first transceiver 78 for transmitting an image capturing end signal or the like, and an image capturing start signal supplied from the image capturing switch 74 and an image capturing condition supplied from the first transceiver 78. It includes a radiation source controller 80 for controlling ().

The host computer 28 transmits and receives the second transceiver 82 and the radiation which transmit and receive necessary information including radiographic image information between the image photographing device 22, the cassette 24, and the display device 26 by wireless communication. An image capturing condition manager 84 that manages image capturing conditions required for the image capturing apparatus 22 for capturing an image, a first image processor 86 for processing radiographic image information transmitted from the cassette 24, and An image memory 88 for storing radiographic image information processed by the one image processor 86, a patient information manager 90 for managing patient information of the patient 14 from which an image is taken, and a cassette 24 And a cassette information manager 92 for managing cassette information transmitted from. The host computer 28 may be located outside the operating room 12 as long as it can transmit and receive signals between the image pickup device 22, the cassette 24, and the display device 26 by wireless communication.

Imaging conditions refer to the conditions required for determining the tube voltage, tube current, irradiation time, etc. required for irradiating the radiation X with an appropriate dose to the portion of the patient 14 to be photographed. Areas, image capturing methods, and the like. Patient information refers to information about the patient 14 required to identify the patient 14, such as the patient's name, gender, age, patient ID number, and the like. The order information indicating the image capturing includes image capturing conditions and patient information may be set directly on the host computer 28 using the console 27 or supplied from an external power source to the host computer 28 via the RIS 146. Can be.

Cassette information may include information about the current state of cassette 24, such as cassette ID information and remaining battery power level. When the cassette information is transmitted from the cassette 24 together with the radiographic image information, the cassette information then adds the cassette ID information and the current state information to confirm the information on the radiographic image information, for example, the image number, the image photographing condition. Number and the like.

The display device 26 includes a receiver 94 for receiving radiation image information from the host computer 28, a display controller 96 for controlling the display of the received radiographic image information, and radiation processed by the display controller 96. And a display unit 98 for displaying image information.

The cassette 24 houses the radiation detector 40, the battery 44, the cassette controller 46, the communication unit 48, and the image memory 102. As shown in FIG. 5, a light emitting element 104 is provided on the side face 34a of the casing 34 of the cassette 24.

As shown in Fig. 6, the cassette controller 46 is a data communication unit for establishing and releasing a link for performing data communication with the host computer 28 and transmitting and receiving data between the host computer 28 via a link ( 106, photographed to acquire image data (unprocessed image data) photographed from the radiation detector 40 by outputting an address signal to the radiation detector 40 based on the reception of the image capturing end signal from the host computer 28. The image data acquisition unit 108 and the image memory 102 are stored in the image transmission buffer 110 and the image memory 102 which temporarily store the transmitted image data. The second image processor 112, which reads the captured image data of the captured image data, matches the transmission request information from the host computer 28, and encrypts the captured image data. Read processing for correction, light correction, defect correction, compression, and the like, and image data stored in the image transmission buffer 110 temporarily and stored in the image transmission buffer 110 (capacity value: Maximum transmission capacity calculator 114 for calculating the amount of the number of bits or the number of bytes), the maximum transmission calculated as text data via the data communication unit 106 to the host computer 28 prior to the transmission of the image data. The capacity value transmitter 116 for transmitting the capacity, the image transmitter 118 for transmitting the image data stored in the image transmission buffer 110 via the data communication unit 106, and the image transmitter 118 receive the image data. And a light emission controller 120 that controls the light emitting element 104 to emit light during the period of transmission.

The image data to be transmitted refers to image data and error correction code data and quantization table data stored in the image transmission buffer 110 by the second image processor 112.

The transmission request information from the host computer 28 indicates, for example, the image capturing condition transmitted to the cassette 24, which is required to start capturing the radiographic image of the patient, and the image capturing end signal indicates that the radiographic image capturing is terminated. When outputting, or an image number is required irrespective of the imaging of the radiographic image.

If the transmission request information from the host computer 28 indicates the image shooting condition, when the next image shooting end signal is input, the second image processor 112 reads out the latest photographed image data stored in the image memory 102, and The readout photographed with the requested image data is processed, and the image data processed and photographed as image data in the image transmission buffer 110 is stored.

If the transmission request information from the host computer 28 indicates the image number, the second image processor 112 reads the photographed image data corresponding to the image number of the photographed image data stored in the image memory 102, The read and processed image data are processed as required, and the image data read and stored as image data in the image transmission buffer 110 is stored. The configuration relationship between the image number and the image data can be registered in a configuration table stored in a data memory different from the image memory 102. The configuration table can be edited and updated by the cassette controller 46 when the image data from the radiation detector 40 is recorded in the image memory 102.

When the image data is sent to the host computer 28, the cassette ID information and the image number are also sent to the host computer 28 so that the host computer 28 easily recognizes the corresponding relationship between the image data and the image number. The transmission request for requesting the image data transmitted based on the image number may be a retransmission request for requesting the retransmitted image data or a transmission request for requesting the image data in another data format transmitted. If the image data already transmitted is uncompressed data, then the transmission request for requesting the image data in another data format is a transmission request for requesting the compressed image data to be transmitted. If the image data already transmitted is compressed data, then the transfer request for requesting the image data of another data format is the transfer request for requesting the transmitted uncompressed image data.

When a communication request signal is input to the data communication unit 106 from any of various components of the cassette controller 46, the data communication unit 106 establishes a link with the host computer 28 prior to data communication with the host computer 28. To establish. When data communication with the host computer 28 ends, the data communication unit 106 releases the link with the host computer 28. After the link with the host computer 28 is released, the data communication unit 106 sends a communication end signal to a communication request signal source that notifies the end of data communication. Specifically, in order to establish a link with the host computer 28, the data communication unit 106 outputs an establishment request signal for establishing a link to the host computer 28, and waits for a response signal from the host computer 28. . When the data communication unit 106 receives the response signal, a link is established to the host computer 28. Thereafter, actual data is transmitted and received from the host computer 28. When the transmission and reception of the data are finished, the data communication unit 106 releases the link. The data communication unit 106 outputs a release request signal for releasing the link to the host computer 28 and waits for a response signal from the host computer 28. When the data communication unit 106 receives the response signal, the link to the host computer 28 is released.

When the second image processor 112 causes the image transmission buffer 110 to store the processed image data, the maximum transmission capacity calculator 114 determines the EOD of the image data stored in the image transmission buffer 110. The number of bits or the number of bytes is calculated as the maximum transmission capacity value from the head address of the image data temporarily stored in End of Data. The EOD represents a code added by the second image processor 112 to the final address of the image data. For example, the calculated maximum transmission capacity value is stored in the register of the CPU.

When the calculation of the maximum transmission capacity value is finished by the maximum transmission capacity calculator 114, the capacity value transmitter 116 reads the maximum transmission capacity value from the register, and transmits the data communication unit 106 to the host computer 28. The maximum transmission capacity value is transmitted via.

The image transmitter 118 transmits the image data stored in the image transmission buffer 110 through the data communication unit 106 to the host computer 28. Preferably, for example, the image transmitter 118 transmits image data by a packet transmission method. Specifically, the image transmitter 118 divides the image data into a constant length of data (a constant amount of data), thereby storing the image data in a constant length of data in each packet and transmitting the packet (first packet transmission process). The image can be transmitted by sending the packet (second packet transmission processing) by storing the various lengths of data in each packet by separating the image data into various lengths of data (various amounts of data). Data can be sent. According to the second packet transmission process, the header of each packet may include information describing the amount of image data stored in the packet, and the EOD code may be added to the last part of the image data stored in each packet.

The light emission controller 120 controls the light emitting element 104 to emit light during the period in which the image transmitter 118 is transmitting image data. Specifically, prior to the transmission of the image data from the image transmitter 118, the light emission controller 120 emits the light emitting element 104 based on the transmission request signal supplied from the image transmitter 118 to the data communication unit 106. To control it. After the transmission of the image data is completed, the light emission controller 200 controls the light emitting element 104 to be turned off based on the communication end signal provided from the data communication unit 106 to the image transmitter 118.

As shown in FIG. 7, the host computer 28, in addition to the components described above with reference to FIG. 4, has a cassette 24 via a second transceiver 82 in the display unit 98 of the display device 26. Data of image data received by the second transceiver 82 during a period during which image data was received, the first indicator display controller 122 displaying an indicator indicating the maximum transmission capacity value received from the upper limit; Value) and a bar image having a length corresponding to the received capacitance value of the image data and moving toward the indicator displayed on the display unit 98, to the display device 26. And a first bar display controller 126 that controls to display.

The image pickup device 22 outputs an image pickup end signal to the cassette 24 when the host image 28 ends. The host computer 28 also transmits image pickup conditions to the cassette 24 and the image pickup device 22. In addition, the host computer 28 transmits the image number input from the console 27 to the cassette 24. The image photographing condition and image number transmitted from the host computer 28 are input to the cassette 24 as a transmission request signal.

For example, the indicator displayed on the display unit 98 of the display device 26 by the first indicator display controller 122 includes a frame image 128 as shown in FIG. 8. Specifically, the first indicator display controller 122 outputs the frame image 128 generated in advance to the display device 26 together with the coordinate data indicating the display position. The display device 26 displays the frame image 128 on the display unit 98 at the position indicated by the coordinate data. The first bar display controller 126 displays the bar image 130 having the leading end at the left end 128a of the frame image 128 and the ending at the right end 128b of the frame image 128.

The reception capacity calculator 124 calculates the data amount of the image data received by the second transceiver 82. According to the packet transmission method, if the amount of image data included in the received packet is constant, then the reception capacity calculator 124 is fixed at a constant number of received packets × number of image data (number of bits or number of bytes). By calculating the amount it is possible to obtain the received capacity value up to now. If the amount of image data included in the received packet is variable, then the receiving capacity calculator 124 calculates the amount of image data contained in the packet by calculating the amount of image data from the head address of the image data of the packet to the EOD code. The amount can be obtained, and the capacity value received so far can be obtained by calculating the amount of image data each time a packet is received and accumulating the calculated amount of image data. If the header of each packet includes information indicating the amount of image data stored in the packet, then the reception capacity calculator 124 accumulates information indicating the amount of image data contained in the packet header each time a packet is received. By doing so, it is possible to obtain the capacity value received so far. The capacity value received so far is stored in a register of the CPU of the host computer 28.

The first bar display controller 126 determines the ratio of the capacitance values received from the cassette 24 to indicate the maximum transmission capacitance value, and generates a bar image 130 that depends on the ratio determined in the frame image 128. The bar image 13 is output to the display device 26 together with the coordinate data. The display unit 98 of the display device 26 currently displays the bar image 130 having a length that matches the capacitance value received so far in the frame image 128. As time elapses, since the received capacitance value of the image data from the cassette 24 increases, the bar image 130 gradually moves toward the end 128b of the frame image 128.

The operation of the image photographing system 10 according to the present invention will be described below.

The imaging system 10 is installed in the operating room 12 and used when a radiographic image of the patient 14 is required by the doctor 18 performing surgery on the patient 14. Before the radiographic image of the patient 14 is taken, patient information of the patient 14 to be photographed is registered in the patient information manager 90 of the host computer 28. If the area of the patient 14 to be imaged and the image capturing method are already known, such information is registered as the image capturing condition in the image capturing condition manager 84. After the preparation process is completed, the doctor 18 performs surgery on the patient 14.

In order to take a radiographic image of the patient 14 during surgery, one of the doctors 18 or radiotechnologists may have the patient side facing the imaging device 22 and the operating table 16 facing the imaging surface 22. The radiation detection cassette 24 is disposed at a predetermined position. At that time, after the image photographing device 22 moves to the position facing the cassette 24, one of the doctor 18 or the radiographer uses the image photographing switch 74 for photographing the radiographic image of the patient 14. Turn on

The radiation source controller 80 of the imaging device 22 controls the radiation source 76 that matches the imaging conditions with respect to the region of the patient that is received and photographed through the first transceiver 78, and thus the dose determined to the patient 14. Irradiate the radiation (X).

Radiation X transmitted through the patient 14 is irradiated to the grid 38 and removes scattered lines from the radiation X. At that time, the radiation X is irradiated to the radiation detector 40 and converted into an electrical signal by the photoelectric conversion layer 51 of the pixel 50 of the radiation detector 40. The electrical signal is stored as charge in the storage capacitor 53 (see FIG. 3). The stored charge represents the radiographic image information of the patient 14, and the storage capacity is obtained by the address signal supplied from the captured image data acquisition unit 108 of the cassette controller 46 to the line scanning driver 58 and the multiplexer 66. Read from 53.

Specifically, the row address decoder 60 of the line scanning driver 58 outputs a selection signal for selecting one first switch in response to the address signal supplied from the captured image data acquisition unit 108, and selects the selected agent. The control signal Von is supplied to the gate of the TFT 52 connected to the gate line 54 coinciding with the one switch SW1. On the other hand, in response to the address signal supplied from the captured image data acquisition unit 108, the row address decoder 68 of the multiplexer 66 is connected to the selected gate line 54 through the signal line 56. A selection signal for continuously turning on the second switch SW2 for switching between the signal lines 56 which reads the charge stored in the storage capacitor 53 of the pixel 50 by it is outputted.

Charges representing the radiographic image information (photographed image data) read out from the storage capacitor 53 of the pixel 50 connected to the selected gate line 54 of the radiation detector 40 are amplified by each amplifier 62. The sample is held by the sample hold circuit 64 and supplied to the multiplexer 66. Based on the supplied charge, the multiplexer 66 generates and supplies a radiographic image signal to the A / D converter 70 and converts the radiographic image signal into a digital signal. A digital signal representing the radiographic image information is stored in the image memory 102 of the cassette controller 46.

Similarly, the row address decoder 60 of the line scanning driver 58 successively switches the first switch SW1 to switch between the gate lines 54 by the address signal supplied from the captured image data acquisition unit 108. Turn on. The charge stored in the storage capacitor 53 of the pixel 50 connected to the continuously selected gate line 54 is read out through the signal line 56, and the multiplexer 66 and the A / D converter 70 are converted into digital signals. Is processed by. The digital signal representing the radiographic image information (photographed image data) is stored in the image memory 102 of the cassette controller 46.

Based on the reception of the image capturing end signal output from the host computer 28, the second image processor 112 reads the latest photographed image data stored in the image memory 102, and the latest photographed image data is read. The image data is processed, and the processed image data is stored in the image transmission buffer 110.

When the second image processor stores image data in the image transmission buffer 110, the maximum transmission capacity calculator 114 calculates a capacity value of the image data (maximum transmission capacity value) and registers the calculated maximum transmission capacity value. Store in

When the maximum transmission capacity calculator 114 finishes calculating the maximum transmission capacity value, the capacity value transmitter 116 reads the maximum transmission capacity value from the register and sends the read maximum transmission capacity value through the data communication unit 106. Send to host computer 28.

Thereafter, the image transmitter 118 transmits the image data stored in the image transmission buffer 110 to the host computer 28 through the data communication unit 106.

During the transmission of the image data, the light emitting element 104 provided on the side surface 34a of the casing 34 emits light under the control of the light emission controller 120. Therefore, the doctor 18 and the radiographer can recognize the image data transmitted to the host computer by watching the light emitting element 104 emit light on the cassette 24.

Based on the maximum transmission capacity value transmitted before the image data, the first indicator display controller 122 of the host computer 28 controls the display device 26 to be displayed on the frame image 128.

While the image data is subsequently received, the reception capacity calculator 124 calculates the received capacity value of the image data, and the first bar display controller 126 is at a ratio of the received capacity value to the maximum transmission capacity value. The display device 26 displaying the bar image 130 having a length to be controlled is controlled.

Therefore, the doctor 18 and the radiographer can immediately know the communication state of the image data by viewing the bar image 130 displayed on the display unit 98 of the display device 26. The display of the bar image 130 is particularly effective for recognizing the communication state of the image data from which the light emission from the light emitting element 104 is difficult to recognize for some reason, and the length of the bar image 130 allows the transmission of the ongoing image data to proceed. Give a clear immediate indication of the condition.

Since the maximum transmission capacity value of the image data is transmitted as text data prior to transmission of the image data, the ratio of the capacity value already received to the maximum transmission capacity value causes the first display controller 126 to generate the bar image 130. Can be accurately determined so that the progress of the transmission of the image data to be sent thereafter can be accurately displayed as a bar image. As a result, transmission of the image data is terminated, but the bar image 130 can be avoided from stopping movement to the end, and the doctor 18 and the radiographer can accurately recognize the progress of the transmission of the image data in progress. Do.

When the reception of the image data is finished, the image data related to the patient information of the patient 14 processed by the first image processor 86 and recorded in the patient information manager 90 is stored in the image memory 88. .

The processed image data is transmitted from the second transceiver 82 to the display device 26. When the display device 26 receives the image data through the receiver 94, the display controller 96 controls the display unit 98 for displaying the radiographic image based on the image data. The doctor 18 performs surgery on the patient 14 while viewing the radiographic image displayed on the display unit 98.

Any cable for transmitting and receiving signals is connected between the cassette 24 and the host computer 28, between the image photographing device 22 and the host computer 28, and between the host computer 28 and the display device 26. Since no cables need to be placed on the floor of the operating room 12, there is no cable-induced obstruction to the work performed by the physician 18, the radiologist, or other members in the operating room.

In the image photographing system 10 according to the present embodiment, as described above, the light emitting element 104 is inserted into the cassette 24 whether the image data is in progress or terminated due to the transmission of image data from the cassette 24 to the host computer 28. Can be easily recognized based on the light emission and the bar image 130 displayed on the display unit 98 of the display device 26. Thus, accidental removal of the battery pack 45 from the cassette is unlikely to occur to the user or to the operator of the host computer 28 to start the next processing while the image data is being transmitted.

In the above embodiment, the light emitting element 104 is provided in the cassette 24. As shown in FIG. 9, in addition to the light emitting element 104, a liquid crystal display unit 132 may also be provided on the side face 34a of the casing 34 of the cassette 24. In this case, as shown in FIG. 10, the cassette controller 46 may further include a second indicator display controller 134 for displaying an indicator, which is set by the maximum transmission capacity calculator 114 as an upper limit. A transmission capacity which indicates the calculated maximum transmission capacity value and calculates the amount of data (transmitted capacity value) of the image data transmitted by the image transmitter 118 in the liquid crystal display unit 132 during the period in which the image data is transmitted. The second bar display controller 138 which controls the calculator 136 and the liquid crystal display unit 132 that displays the bar image has a length that matches the transmitted capacitance value of the image data. In Fig. 10, the image transmission buffer 110 and any other configuration shown in Fig. 6 are not shown.

For example, as shown in FIG. 11, the indicator is displayed on the liquid crystal display unit 132 by the second indicator display controller 134 including the plane image 140. Specifically, the second indicator display controller 134 outputs the frame image 140 generated in advance to the liquid crystal display unit 132 together with the coordinate data indicating the display position. The liquid crystal display unit 132 displays the frame image 140 at the position indicated by the coordinate data. The second bar display controller 138 displays the bar image 142 having an end on the left end 140a of the frame image 140 at the right end 140b of the leading frame image 140.

The transmitted capacity calculator 136 calculates the data amount of the image data transmitted by the image transmitter 118. According to the packet transmission method, if the amount of image data included in the transmitted packet is constant, then the transmitted capacity calculator 136 determines a fixed amount of the number of the transmitted packet × number of image data (number of bits or bytes) at that time. By calculating, the capacity value transmitted so far can be obtained. If the amount of image data contained in the transmitted packet is variable, then the transmitted capacity calculator 136 calculates the amount of image data in the EOD code of the packet from the head address of the image data to determine the amount of image data contained in the packet. The amount can be obtained, and at that time, the capacity value transmitted so far can be obtained by calculating the amount of image data for each time the packet is transmitted and accumulating the calculated amount of image data. If each packet header includes information indicating the amount of image data stored in the packet, then the capacity calculator 136 transmitted at that time receives information indicating the amount of image data included in the packet header for each time the packet is received. By accumulating, it is possible to obtain the transmitted capacity value to date. For example, the capacitance value transmitted so far is stored in the register of the CPU of the cassette controller 46.

The second bar display controller 138 determines the ratio of the capacity values transmitted from the cassette 24 to the present maximum transmission capacity value, and generates a bar image 142 that depends on the ratio determined in the frame image 140. And the bar image 142 is output to the liquid crystal display unit 132 with coordinate data. The liquid crystal display unit 132 now displays the bar image 142 having a length that matches the capacitance value transmitted so far in the frame image 140. As time elapses, since the transmitted capacitance value of the image data from the cassette 24 increases, the bar image 142 gradually moves toward the end 140b of the frame image 140.

When the operator who operates the cassette 24 returns the cassette 24 after photographing the radiographic image there, the operator knows that the image data is to be transmitted from the cassette 24 by viewing the light emission of the light emitting element 104. It can be recognized and prevents the battery pack 45 from being accidentally removed from the cassette 24. The operator can also clearly recognize the progress of the transmission of the image data in progress by viewing the bar image 142, which is the same as the transmitted capacitance value and is displayed on the liquid crystal display unit 132 on the cassette 24.

A preferred detailed configuration of the image photographing system 10 according to an embodiment of the present invention, in particular the cassette 24, will be described below.

The casing 34 of the cassette 24 preferably has communication holding means for maintaining the transmission of the image data during the period in which the image data is transmitted.

As shown in Fig. 12, when the battery pack 45 is installed in the casing 34, the communication holding means opens the battery pack 45 for separation from the casing 34 at least during the period in which image data is being transmitted. And a first locking mechanism 144 for locking.

The first lock mechanism 144 is mounted to the bottom plate 147 of the casing 34 and is a stopper plate 150 having a rectangular, semicircular, or polygonal shape that is rotatable about an axis 149, for example. For example, one drive mechanism 152 (solenoid or electric motor) for selectively rotating the stopper plate 150 in two directions. For example, a first direction for pressing the battery pack 45 and a second direction for releasing the battery pack 45. The first direction is preferably a direction for preventing the movement of the battery pack 45. For example, as shown in FIG. 12, if the battery pack 45 is removed from the casing 34 as it moves horizontally, the stopper plate 150 then presses a portion of the battery pack 45 horizontally. It is desirable to prevent the movement to. The second direction is preferably smoothly horizontally moved in the direction of releasing the battery pack 45 from the pressurized state.

If the first drive mechanism 152 includes a solenoid, not shown, then the stopper plate 150 is connected to the stopper plate 150 by a non-illustrated leaf spring connected to the stopper plate 150 while the solenoid is not driven. Pressurize normally to move in the second direction to release it. At least while the image data is being transmitted, the solenoid is driven by rotating the stopper plate 150 in the first direction to prevent bias of the leaf spring, thereby preventing the removal from the casing 34 to pressurize the battery pack 45. do. If the first drive mechanism 152 includes an electric motor, it is connected to a shaft 149 which selectively rotates the stopper plate 150 in the first and second directions, not shown, at which time the stopper plate 150 Is rotated in the second direction when the electric motor drives to rotate the shaft 149 in one direction, and the stopper plate 150 is driven when the electric motor drives to rotate the shaft 149 in the other direction. Rotate in the first direction.

As shown in FIG. 13, the cassette controller 46 has a stopper movement controller 154. In Fig. 13, the image transmission buffer 110 and the somewhat different components shown in Fig. 6 are not shown.

Prior to the transmission of the image data from the image transmitter 118, the stopper movement controller 154 first presses the battery pack 45 on the basis of the communication request signal output from the image transmitter 118 to the data communication unit 106. The 1st drive mechanism 152 which rotates the stopper plate 150 in the direction is controlled. After the transmission of the image data is completed, the stopper movement controller 154 releases the stopper plate in the second direction in which the battery pack 45 is released based on the communication completion signal output from the data communication unit 106 to the image transmitter 118. The first drive mechanism 152 that rotates 150 is controlled.

Therefore, at least while the image data is being transmitted, the battery pack 45 cannot be removed from the casing 34. The battery pack 45 is thus prevented from being accidentally removed from the casing 34 during the transmission of the image data.

The communication holding means may be another structure applicable to the cable connected to the cassette 24. In the previous configuration shown in FIG. 12, the various components housed in the cassette 24 are powered from a battery 44 housed in a battery pack 45 located in the cassette 24. However, various components housed in cassette 24 may be powered from an external power supply via a power cable. Alternatively, the various components housed in the cassette may be powered from the battery 44 and the cassette 24 may be capable of communicating with the host computer 28 via a communication cable.

If a power cable or communication cable is connected to the cassette 24, then the cable should not be disconnected while image data is being transmitted.

As shown in FIG. 14, the cable 156 has a plug 158 inserted into the casing 34 and is inserted into the connector 160 of the cassette 24. The communication holding means of another configuration includes a second lock mechanism 162 which at least prevents the cable 156 from being disconnected from the cassette 24 while image data is being transmitted.

The second lock mechanism 162 is a wedge shaped hook disposed close to the connector 160, rotatable about the shaft 164, and a second drive mechanism 170 (solenoid or to selectively rotate the hook in two directions). Electric motor), for example, a first direction engaging with the hole 168 provided in the plug 158 and a second direction separating from the hole 168 provided in the plug 158. When the hook 166 engages the hole 168, the cable 156 cannot be easily separated from the cassette 24.

If the second drive mechanism 170 includes a solenoid, not shown, then the hook 166 is transferred to the hole 168 by an unshown leaf spring connected to the hook 166 while the solenoid is not driven. Normally pressurizes the rotation in the second direction. At least while the image data is being transmitted, the solenoid drives the rotation of the hook 166 in the first direction by preventing the bias of the leaf spring, thereby positioning the hook 166 in the hole 168. If the second drive mechanism 170 includes an electric motor, it is connected to a shaft 164 that selectively rotates the hook 166 in the first and second directions, not shown, in which case the hook 166 is connected to the electric motor. Is connected to a shaft 164 which rotates the shaft 164 in one direction, and the hook 166 is then rotated in the second direction when the electric motor drives the shaft 164 to rotate in one direction, The hook 166 rotates in the first direction when the electric motor drives the shaft 164 to reversely rotate in the other direction.

As shown in FIG. 15, the cassette controller 46 has a hook movement controller 172. In FIG. 15, the image transmission buffer 110 and somewhat other components shown in FIG. 6 are omitted from the drawing.

Prior to the transmission of the image data from the image transmitter 118, the hook movement controller 172 moves the second drive mechanism 170 from the image transmitter 118 to the data communication unit 106 based on the communication request signal output. The hook 166 is controlled to rotate in the first direction in which the hook 166 is positioned in the 168. After the transmission of the image data is finished, the hook movement controller 172 transfers the second drive mechanism 170 from the data communication unit 106 to the image transmitter 118 based on the communication completion signal output and the hole 168 moves out. The hook 166 is controlled to rotate in the second direction.

Therefore, at least image data cannot be separated from the cable 34 while being transmitted. The cable 156 is thus prevented from being accidentally disconnected from the cassette 24 during the transmission of the image data.

In the radiographic imaging system 10 according to the illustrated embodiment, the radiation detector 40 is housed in a cassette 24 which directly converts the dose of radiation X irradiated with the electrical signal by the photoelectric conversion layer 51. do. However, the radiographic imaging system 10 includes a scintillator for converting radiation X incident to visible light and amorphous silicon (a-Si) for converting visible light into an electrical signal (see Japanese Patent Laid-Open No. 3494683). It is possible to use a radiation detector including a solid element detection device such as the like.

Alternatively, the radiographic imaging system 10 may acquire radiographic image information using a light conversion radiation detector. The light conversion radiation detector functions as follows: When the radiation is irradiated in the matrix shape of the solid state element detecting apparatus, the solid state element detecting apparatus stores an electrostatic latent image that depends on the irradiation amount of irradiated radiation. For reading out the stored electrostatic latent image, the read light is irradiated to the solid state element detecting apparatus which generates a current so that the solid state element detecting apparatus displays the radiographic image information. When the erasing light is irradiated to the radiation detector, the radiographic image information indicating the residual electrostatic latent image is erased from the radiation detector and thus can be reused (see Japanese Patent Laid-Open No. 2000-105297).

When the cassette 24 is used in the operating room 12 or the like, the cassette 24 may be attached with blood, various bacteria, and the like. However, when the radiation detection cassette 24 is designed to have a waterproof and hermetic structure, it is sterilized and cleaned as needed, and one cassette 24 can be used repeatedly.

The cassette 24 is not limited to use in the operating room 12, but may be used for medical systems and rounds of the hospital.

In addition, the cassette 24 may communicate with an external device via optical wireless communication using infrared light or the like instead of general wireless communication using radio waves.

Preferably, the cassette 500 may be configured as shown in FIG.

Specifically, the cassette 500 includes a guiding line 504 shown on the irradiation surface of the casing 502, and the guiding line 504 serves as a reference for setting the photographing area and the photographing position. The use of the guiding line 504 allows the subject 14 to be positioned relative to the cassette 500, and the area to which the radiation X is radiated can be set, whereby the radiographic image information can be properly photographed. You can write to the area.

The cassette 500 is provided with a display portion 506 in its area other than the photographed area that displays various information about the cassette 500. The information displayed on the display unit 506 includes information about the subject 14 on which the radiographic image information is recorded in the cassette 500, the number of times the cassette 500 is used, the amount of radiation accumulated and irradiated, and the battery 44 in the cassette 500. ), The state of charge (remaining capacity), the image capturing conditions of the radiographic image information, and the ID information of the subject of the image located on the subject 14 with respect to the cassette 500. In this case, the technician checks the subject 14 on the basis of the ID information displayed on the display unit 506, and also confirms in advance that the cassette 500 is positioned in an unusable state, for example. At that time, the technician captures the appropriate radiographic image information by positioning the desired photographing area of the subject 14 with respect to the cassette 500 based on the displayed image displayed.

In addition, the cassette 500 is provided with a hand grip 508 for easier operation and transportation of the cassette 500.

Preferably, the cassette 500 may have an input terminal 510, a universal serial bus (USB) terminal 512, and a card slot 516 for inserting a memory card 514 as an AC adapter on one side.

When the charging action of the battery 44 in the cassette 500 is degraded, or when there is not enough time for the battery 44 to be fully charged, the input terminal 510 supplies power to the cassette 500 from the outside to supply AC. It is possible to connect to an adapter, whereby the cassette 500 can be used immediately.

The USB terminal 512 or card slot 516 may be used when the cassette 500 cannot transmit or receive information via wireless communication between external devices such as the host computer 28. In detail, by connecting a cable to the USB terminal 512, the cassette 500 may transmit and receive information between external devices through wired communication. Alternatively, the memory card 514 is inserted into the card slot 516 and the necessary information is recorded in the memory card 514. Thereafter, the memory card 514 is removed from the card slot 516, and the information can be transmitted by inserting the memory card 514 into the external device.

Preferably, cradle 518 may be placed in operating room 12 or as desired in a hospital, and cassette 24 is inserted to charge internal battery 44, as shown in FIG. In this case, in addition to charging the battery 44, the cradle 518 may be externally connected, such as HIS 148, RIS 146, host computer 28 by wired or wireless communication of cradle 518. The necessary information can be transmitted and received between the devices. The information may include radiographic image information recorded in the cassette 24 inserted into the cradle 518.

In addition, the cradle 518 may be provided with a display unit 520. The display unit 520 can display necessary information including a state of charge inserted into the cassette 24 and radiographic image information acquired from the cassette 24.

In addition, the plurality of cradles 518 may be connected to the network. In this case, information on the state of charge of the cassette 24 inserted into each cradle 518 can be collected via the network, and the cassette 24 can be positioned in an unusable state.

While certain preferred embodiments of the invention have been shown and described in detail, it is understood that various changes and modifications can be made without departing from the scope of the appended claims.

1 is a perspective view of an operating room in which a radiographic imaging system (an imaging system) according to one embodiment of the present invention is installed;

2 is a partially cutaway perspective view showing a detailed internal structure of the radiation detection cassette used in the radiographic imaging system;

3 is a block diagram of the circuit arrangement of the radiation detector of the radiation detection cassette;

4 is a block diagram of a radiographic imaging system according to the embodiment;

5 is a perspective view of a radiation detection cassette in which a light emitting element is provided on one side;

6 is a block diagram of a cassette controller of a radiation detection cassette;

7 is a block diagram illustrating the functionality of a host computer displaying a bar;

8 is a diagram illustrating an example of a frame image and a bar image displayed on the display panel of the display device;

9 is a perspective view of a radiation detection cassette in which a liquid crystal display device is provided on one side;

FIG. 10 is a block diagram of a cassette controller partially omitted from the illustration for controlling the liquid crystal display shown in FIG. 9;

11 is a diagram showing an example of a frame image and a bar image displayed on the liquid crystal display;

12 is a block diagram of a first lock mechanism;

FIG. 13 is a block diagram of a cassette controller partially omitted from the illustration for controlling the first lock mechanism shown in FIG. 12;

14 is a view of a second lock mechanism;

FIG. 15 is a block diagram of a cassette controller partially omitted from the illustration for controlling the second lock mechanism shown in FIG. 14;

16 is a perspective view showing a radiation detection cassette according to another embodiment of the present invention;

17 is a perspective view showing a cradle filling a radiation detection cassette.

Claims (11)

Casing 34; A radiation conversion panel (40) which is accommodated in the casing (34) and detects radiation (X) transmitted through the subject (14) and converts the detected radiation into radiographic image information; A memory 102 for storing the radiographic image information stored in the casing 34 and converted by the radiation conversion panel 40; A communication unit (48) housed in the casing (34) for transmitting at least the radiographic image information to an external device; A controller 46 accommodated in the casing 34; And And a communication holding unit housed in the casing (34) to hold the radiographic image information transmitted for at least the period during which the communication unit (48) is transmitting the radiographic image information. The method of claim 1, A battery pack (45) housed in the casing (34); The communication holding unit includes a lock mechanism 144 which prevents the battery pack 45 from being removed from the casing 34 at least during the period in which the communication unit 48 is transmitting the radiographic image information. And a radiation detection cassette. The method of claim 1, A connector (160) received in the casing (34) to connect a cable (156); The communication holding unit includes a lock mechanism 162 for preventing the cable 156 from being disconnected from the connector 160 for at least the period during which the communication unit 48 is transmitting the radiographic image information. Radiation detection cassette. The method according to any one of claims 1 to 3, Further comprising a light emitting element (104) mounted on a surface of the casing (34); The controller 46 includes a light emitting controller 120 which controls the light emitting element 104 to emit light during the period in which the communication unit 48 is transmitting the radiographic image information. . The method according to any one of claims 1 to 4, A display unit (132) mounted on a surface of the casing (34); The controller 46 includes a communication display controller 138 which controls the display unit 132 to display the transmission of the radiographic image information during the period in which the communication unit 48 is transmitting the radiographic image information. A radiation detection cassette, characterized in that. A casing 34, a radiation conversion panel 40 for detecting radiation transmitted to the casing 34 and passing through the subject and converting the detected radiation into radiographic image information, and a radiation conversion panel accommodated in the casing ( In the memory 102 which stores the radiographic image information converted by 40, the communication unit 48 which is accommodated in the casing 34, and transmits at least the said radiographic image information to an external device, and the said casing 34 A radiation detection cassette 24 comprising a cassette controller 46 housed therein; An image photographing device (22) for radiating radiation (X) onto said subject (14); A host computer (28) for exchanging information with the radiation detection cassette (24) to control the image photographing device (22); And A medical system comprising a display device 26 for displaying information from the host computer 28: The cassette controller 46 is a capacitance value transmitter 116 for transmitting the capacitance value of the radiation image information to the host computer 28 before the radiation image information is transmitted, and an image information transmitter for transmitting the radiation image information. 118; The host computer 28 controls the display device 26 to display an indicator 128 indicating the capacitive value received from the radiation detection cassette 24 as an upper limit, and the display device. A bar image displaying a bar image 130 which is controlled to move toward the displayed indicator 128 during the period in which the radiographic image information is being received so as to have a length corresponding to the reception capacitance value of the radiographic image information. A medical system comprising a controller (126). The method of claim 6, The radiation detection cassette 24 includes a communication holding unit housed in the casing 34 to hold the radiographic image information transmitted for at least the period during which the communication unit 48 is transmitting the radiographic image information. Characterized by a medical system. The method of claim 7, wherein The radiation detection cassette (24) comprises a battery pack (45) housed in the casing (34); The communication holding unit includes a lock mechanism 144 which prevents the battery pack 45 from being removed from the casing 34 at least during the period in which the communication unit 48 is transmitting the radiographic image information. Characterized by a medical system. The method of claim 7, wherein The radiation detection cassette (24) includes a connector (160) received in the casing (34) to connect a cable (156); The communication holding unit includes a lock mechanism 162 for preventing the cable 156 from being disconnected from the connector 160 for at least the period during which the communication unit 48 is transmitting the radiographic image information. Medical system. The method according to any one of claims 6 to 9, The radiation detection cassette (24) comprises a light emitting element (104) mounted on the surface of the casing (34); The cassette controller 46 includes a light emission controller 120 which controls the light emitting element 104 to emit light during the period in which the communication unit 48 is transmitting the radiographic image information. . The method according to any one of claims 6 to 10, The radiation detection cassette (24) includes a display unit (132) mounted on the surface of the casing (34); The cassette controller 46 includes a communication display controller 138 which controls the display unit 132 to display the transmission of the radiographic image information during the period in which the communication unit 48 is transmitting the radiographic image information. Medical system, characterized in that.

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