JP2022105936A - Detector module and radiation detector - Google Patents

Abstract

To control the cooling of a detector module on a module-by-module basis.SOLUTION: A detector module 121 having a plurality of detector elements for detecting radiation includes a flow channel 1215 and a micropump 1216, which is a circulating part. The flow channel 1215 has a refrigerant inside. The micropump 1216, which is the circulation part, circulates the refrigerant within the flow channel 1215.SELECTED DRAWING: Figure 3

Description

The embodiments disclosed herein and in the drawings relate to a detector module and a radiation detector.

Conventionally, as a radiation detector used in a radiation diagnostic device such as an X-ray CT (Computed Tomography) device or a PET (Positron Emission Tomography) device, a radiation detector configured by arranging a plurality of detector modules is known. ing. In such a radiation detector, the detection element, the circuit board, etc. included in each detector module generate heat when irradiated with radiation, and therefore, in general, the image quality of the captured image deteriorates or fails due to the heat generated by the detector module. The detector module is cooled for the purpose of preventing.

Japanese Patent Application Laid-Open No. 2003-130961 JP-A-2009-254816 JP-A-2019-18021

One of the problems to be solved by the embodiments disclosed in the present specification and the drawings is to control the cooling of the detector module for each module. However, the problems to be solved by the embodiments disclosed in the present specification and the drawings are not limited to the above problems. It is also possible to position the problem corresponding to each effect by each configuration shown in the embodiment described later as another problem.

The detector module according to the embodiment is a detector module having a plurality of detection elements for detecting radiation, and includes a flow path and a circulation unit. The flow path is provided with a refrigerant inside. The circulation unit circulates the refrigerant in the flow path.

FIG. 1 is a diagram showing a configuration example of an X-ray CT device according to the first embodiment. FIG. 2 is a diagram showing a configuration example of the X-ray detector according to the first embodiment. FIG. 3 is a diagram showing a configuration example of the detector module according to the present embodiment. FIG. 4 is a flowchart showing a processing procedure of processing performed by the processing circuit according to the first embodiment. FIG. 5 is a diagram showing an example of cooling control by the bypass flow path and the control function according to the second embodiment. FIG. 6 is a diagram showing another example of cooling control by the bypass flow path and the control function according to the second embodiment. FIG. 7 is a flowchart showing a processing procedure of processing performed by the processing circuit according to the second embodiment.

(First Embodiment)
Hereinafter, embodiments of the detector module and the radiation detector disclosed in the present application will be described with reference to the drawings. Here, the configuration shown in each drawing is schematic, and the dimensions of each component and the ratio of the dimensions between the components shown in the drawings may differ from the actual ones. Further, the dimensions of the same component and the ratio of the dimensions between the components may be shown differently between the drawings.

In the embodiment shown below, an example will be described in which the configurations of the detector module and the radiation detector disclosed in the present application are applied to the X-ray detector and the X-ray CT device.

FIG. 1 is a diagram showing a configuration example of an X-ray CT device according to the first embodiment.

For example, as shown in FIG. 1, the X-ray CT device 1 according to the present embodiment includes a gantry device 10, a bed device 30, and a console device 40. Note that FIG. 1 shows a plurality of gantry devices 10 for convenience of explanation.

In the present embodiment, the rotation axis of the rotation frame 13 in the non-tilt state or the longitudinal direction of the top plate 33 of the sleeper device 30 is orthogonal to the Z-axis direction and the Z-axis direction, and is horizontal to the floor surface. Is orthogonal to the X-axis direction and the Z-axis direction, and the axial direction perpendicular to the floor surface is defined as the Y-axis direction, respectively.

The gantry device 10 is a device that irradiates a subject P (patient or the like) with X-rays, detects the X-rays transmitted through the subject P, and outputs the X-rays to the console device 40. The gantry device 10 includes an X-ray tube 11, an X-ray detector 12, a rotating frame 13, a control device 15, a wedge 16, an X-ray throttle 17, and an X-ray high voltage device 14.

The X-ray tube 11 is a vacuum tube that generates X-rays by irradiating thermoelectrons from the cathode (filament) toward the anode (target) by applying a high voltage from the X-ray high voltage device 14. For example, the X-ray tube 11 is a rotating anode type X-ray tube that generates X-rays by irradiating a rotating anode with thermions.

The wedge 16 is a filter for adjusting the X-ray dose emitted from the X-ray tube 11. Specifically, the wedge 16 transmits and attenuates the X-rays emitted from the X-ray tube 11 so that the X-rays emitted from the X-ray tube 11 to the subject P have a predetermined distribution. It is a filter to do. For example, the wedge 16 is a filter obtained by processing aluminum so as to have a predetermined target angle and a predetermined thickness. The wedge 16 is also called a wedge filter or a bow-tie filter.

The X-ray diaphragm 17 includes a lead plate or the like for narrowing the irradiation range of X-rays transmitted through the wedge 16, and a slit is formed by combining a plurality of lead plates or the like.

The X-ray detector 12 detects X-rays irradiated from the X-ray tube 11 and passed through the subject P. Specifically, the X-ray detector 12 has a plurality of detection element trains in which a plurality of detection elements are arranged in the channel direction along one arc centering on the focal point of the X-ray tube 11. For example, the X-ray detector 12 has a structure in which a plurality of detection element sequences in which a plurality of detection elements are arranged in the channel direction are arranged in a row direction (also referred to as a slice direction or a row direction).

For example, the X-ray detector 12 is an indirect conversion type detector having a grid, a scintillator array, and an optical sensor array. The scintillator array has a plurality of scintillators, and the scintillator has a scintillator crystal that outputs a photon amount of light according to an incident X dose. The grid is arranged on the surface of the scintillator array on the X-ray incident side and has an X-ray shielding plate having a function of absorbing scattered X-rays. The grid may also be called a collimator (one-dimensional collimator or two-dimensional collimator). The optical sensor array has a function of converting into an electric signal according to the amount of light from the scintillator. For example, the photomultiplier tube (photomultiplier: has an optical sensor such as PMT. The X-ray detector 12 has an optical sensor. It may be a direct conversion type detector having a semiconductor element that converts incident X-rays into an electric signal.

Further, the X-ray detector 12 has a DAS (Data Acquisition System) substrate that processes an electric signal output from each detection element. The DAS board has an amplifier that amplifies the electric signal output from each detection element of the X-ray detector 12, and an A / D converter that converts the electric signal into a digital signal, and stores the detection data. Generate. The detection data generated by the DAS board is transferred to the console device 40.

The X-ray high-voltage device 14 has an electric circuit such as a transformer and a rectifier, and has a function of generating a high voltage applied to the X-ray tube 11 and an irradiation by the X-ray tube 11. It has an X-ray control device that controls an output voltage according to the X-ray output. The high voltage generator may be a transformer type or an inverter type. The X-ray high voltage device 14 may be provided on a rotating frame 13 described later, or may be provided on a support frame (not shown) that rotatably supports the rotating frame 13 in the gantry device 10.

The rotating frame 13 is an annular frame that supports the X-ray tube 11 and the X-ray detector 12 so as to face each other and rotates the X-ray tube 11 and the X-ray detector 12 by a control device 15 described later. The rotating frame 13 further includes and supports an X-ray high voltage device 14 in addition to the X-ray tube 11 and the X-ray detector 12.

Here, the rotating frame 13 is rotatably supported by a non-rotating portion (for example, a fixed frame; not shown in FIG. 1) of the gantry device 10. The rotation mechanism includes, for example, a motor that generates a rotation driving force and a bearing that transmits the rotation driving force to the rotation frame 13 to rotate the motor. The motor is provided, for example, in the non-rotating portion, the bearing is physically connected to the rotating frame 13 and the motor, and the rotating frame 13 rotates according to the rotational force of the motor.

Further, a non-contact type or contact type communication circuit is provided in each of the rotating frame 13 and the non-rotating portion, whereby the unit supported by the rotating frame 13 and the non-rotating portion or the external device of the gantry device 10 are provided. Communication takes place. For example, when optical communication is adopted as a non-contact communication method, the detection data generated by the DAS substrate is transmitted by optical communication from a transmitter having a light emitting diode (LED) provided in the rotating frame 13. It is transmitted to a receiver having a photodiode provided in the non-rotating portion of 10, and further transferred from the non-rotating portion to the console device 40 by the transmitter. As the communication method, in addition to the non-contact type data transmission method such as the capacitance coupling type and the radio wave method, a contact type data transmission method using a slip ring and an electrode brush may be adopted.

The control device 15 has a processing circuit having a CPU (Central Processing Unit) and the like, and a drive mechanism such as a motor and an actuator. The control device 15 has a function of receiving an input signal from the input interface 43 attached to the console device 40 or the gantry device 10 and controlling the operation of the gantry device 10 and the bed device 30. For example, the control device 15 controls to rotate the rotating frame 13 in response to an input signal, controls to tilt the gantry device 10, and controls to operate the bed device 30 and the top plate 33. The control for tilting the gantry device 10 is such that the control device 15 rotates around an axis parallel to the X-axis direction based on the tilt angle (tilt angle) information input by the input interface 43 attached to the gantry device 10. It is realized by rotating 13. The control device 15 may be provided in the gantry device 10 or in the console device 40.

The bed device 30 is a device for placing and moving the subject P to be scanned, and has a base 31, a bed drive device 32, a top plate 33, and a support frame 34. The base 31 is a housing that supports the support frame 34 so as to be movable in the vertical direction. The bed drive device 32 is a motor or an actuator that moves the top plate 33 on which the subject P is placed in the long axis direction of the top plate 33. The top plate 33 provided on the upper surface of the support frame 34 is a plate on which the subject P is placed. In addition to the top plate 33, the bed drive device 32 may move the support frame 34 in the long axis direction of the top plate 33.

The console device 40 is a device that accepts the operation of the X-ray CT device 1 by the operator and reconstructs the CT image data using the detection data collected by the gantry device 10. The console device 40 includes a memory 41, a display 42, an input interface 43, and a processing circuit 44. Here, an example in which the console device 40 and the gantry device 10 are separate bodies will be described, but the gantry device 10 may include a part of the console device 40 or the components of the console device 40.

The memory 41 is realized by, for example, a RAM (Random Access Memory), a semiconductor memory element such as a flash memory, a hard disk, an optical disk, or the like. The memory 41 stores, for example, projection data and CT image data.

The display 42 displays various information. For example, the display 42 outputs a medical image (CT image) generated by the processing circuit 44, a GUI (Graphical User Interface) for receiving various operations from the operator, and the like. For example, the display 42 is a liquid crystal display or a CRT (Cathode Ray Tube) display. In addition, for example, the display 42 may be provided in the gantry device 10. Further, for example, the display 42 may be a desktop type or may be configured by a tablet terminal or the like capable of wireless communication with the console device 40 main body.

The input interface 43 receives various input operations from the operator, converts the received input operations into electric signals, and outputs the received input operations to the processing circuit 44. For example, the input interface 43 receives from the operator scan conditions for collecting projection data, reconstruction conditions for reconstructing CT image data, image processing conditions for generating post-processed images from CT images, and the like. accept. For example, the input interface 43 is realized by a mouse, a keyboard, a trackball, a switch, a button, a joystick, or the like. In addition, for example, the input interface 43 may be provided in the gantry device 10. Further, for example, the input interface 43 may be configured by a tablet terminal or the like capable of wireless communication with the console device 40 main body.

The processing circuit 44 controls the operation of the entire X-ray CT device 1. For example, the processing circuit 44 executes the system control function 441, the preprocessing function 442, the reconstruction processing function 443, and the image processing function 444.

The system control function 441 controls various functions of the processing circuit 44 based on the input operation received from the operator via the input interface 43. For example, the system control function 441 controls the CT scan performed in the X-ray CT apparatus 1. Further, the system control function 441 controls the generation and display of CT image data in the console device 40 by controlling the pre-processing function 442, the reconstruction processing function 443, and the image processing function 444.

The preprocessing function 442 is a projection data in which the detection data output from the DAS of the X-ray detector 12 is subjected to preprocessing such as logarithmic conversion processing, offset correction processing, sensitivity correction processing between channels, and beam hardening correction. To generate. The data before preprocessing (detection data) and the data after preprocessing may be collectively referred to as projection data.

The reconstruction processing function 443 performs reconstruction processing using a filter correction back projection method, a successive approximation reconstruction method, or the like on the projection data generated by the preprocessing function 442, and performs CT image data (reconstruction image). Data) is generated.

The image processing function 444 uses a known method to obtain CT image data of an arbitrary cross section or three-dimensional image data generated by the reconstruction processing function 443 based on an input operation received from the operator via the input interface 43. Convert to image data. The reconstruction processing function 443 may directly generate the three-dimensional image data.

Here, for example, the processing circuit 44 is realized by a processor. In this case, each processing function of the processing circuit 44 is stored in the memory 41 in the form of a program that can be executed by a computer. Then, the processing circuit 44 realizes a function corresponding to each program by reading each program from the memory 41 and executing the program. In other words, the processing circuit 44 in the state where each program is read out has each processing function shown in the processing circuit 44 of FIG.

In addition, although it has been described here that each of the above-mentioned processing functions is realized by a single processing circuit 44, for example, a plurality of independent processors are combined to form a processing circuit 44, and each processor constitutes a program. Each processing function may be realized by executing it. Further, each processing function of the processing circuit 44 may be appropriately distributed or integrated into a single or a plurality of processing circuits. Further, each processing function of the processing circuit 44 may be realized by mixing hardware such as a circuit and software. Further, here, an example in which a single memory 41 stores a program corresponding to each processing function has been described, but the embodiment is not limited to this. For example, a plurality of storage circuits may be distributed and arranged, and the processing circuit 44 may read the corresponding program from the individual storage circuits and execute the corresponding program.

The overall configuration of the X-ray CT device 1 according to the present embodiment has been described above. Under such a configuration, in the present embodiment, the X-ray detector 12 is configured by arranging a plurality of detector modules having a plurality of detection elements.

FIG. 2 is a diagram showing a configuration example of the X-ray detector 12 according to the first embodiment.

For example, as shown in FIG. 2, the X-ray detector 12 is formed in a substantially arc shape as a whole, and the center of the arc is aligned with the position of the X-ray tube 11, and the rotating frame 13 is formed. Is fixed to. Here, the circumferential direction of the arc of the X-ray detector 12 coincides with the channel direction, the axial direction coincides with the column direction, and the radial direction coincides with the X-ray irradiation direction.

The X-ray detector 12 includes a plurality of detector modules 121 and a processing circuit 122.

The plurality of detector modules 121 are arranged in the channel direction, and each has a plurality of detector elements for detecting X-rays. For example, the detector module 121 is fixed to a support member included in the X-ray detector 12 in a state of being arranged in the channel direction.

The processing circuit 122 transfers the detection data output from each detector module 121 to the console device 40. For example, the processing circuit 122 is mounted on a control board included in the X-ray detector 12.

Here, in an X-ray detector in which such a plurality of detector modules are arranged, it is known that the detection element, the circuit board, and the like included in each detector module generate heat when X-rays are irradiated. .. Therefore, in general, in the X-ray detector, the detector module is cooled for the purpose of preventing deterioration of image quality and failure of the captured image due to heat generation of the detector module.

For example, as such a cooling method, a plurality of circuit boards of each detector module are cooled by air cooling or by liquid cooling using a cooling unit such as a chiller provided on a rotating frame. There is a way to cool the detector module as a whole.

However, in an X-ray detector in which a plurality of detector modules are arranged, the dose of X-rays incident on each detector module differs depending on the position where the subject is placed on the top plate, scanning conditions, etc., so that detection is usually performed. The calorific value changes for each device module. Therefore, in the method of cooling a plurality of detector modules as a whole as described above, some of the detector modules may be insufficiently cooled, and as a result, the image quality of the captured image may deteriorate or the detector module may fail. It can happen. In addition, the method of cooling a plurality of detector modules as a whole can make the cooling system large and expensive.

Therefore, in the present embodiment, the X-ray detector 12 is configured so that the cooling of the detector module 121 can be controlled for each module.

Specifically, in the present embodiment, each detector module 121 included in the X-ray detector 12 includes a flow path having a refrigerant inside and a micropump for circulating the refrigerant in the flow path. Here, the micropump is an example of a circulation part.

FIG. 3 is a diagram showing a configuration example of the detector module 121 according to the present embodiment.

For example, as shown in FIG. 3, the detector module 121 includes a detection unit 1211, a DAS substrate 1212, a support mechanism portion 1213, a substrate cover 1214, a flow path 1215, and a micropump 1216.

The detection unit 1211 has a plurality of detection elements for detecting X-rays, and outputs an electric signal output from each detection element to the DAS substrate 1212. For example, the detection unit 1211 includes a plurality of detection elements arranged two-dimensionally along the channel direction and the column direction, and an ASIC that processes an electric signal output from each detection element.

The DAS substrate 1212 generates and outputs detection data based on the electrical signal output from the detection unit 1211. For example, the DAS board 1212 has an amplifier that amplifies the electric signal output from the detection unit 1211 and an A / D conversion that converts the electric signal amplified by the amplifier into a digital signal to generate detection data. Including vessels.

The support mechanism unit 1213 supports the detection unit 1211, the DAS substrate 1212, the micropump 1216, and the substrate cover 1214. For example, the support mechanism unit 1213 is formed in a substantially rectangular cuboid shape extending in the X-ray irradiation direction, supports the detection unit 1211 on the surface on the X-ray incident side, and supports the DAS substrate 1212 on one surface in the channel direction.

The board cover 1214 protects the DAS board 1212. For example, the substrate cover 1214 is arranged so as to cover the DAS substrate 1212 along the X-ray irradiation direction, and one end portion in the X-ray irradiation direction is fixed to the support mechanism portion 1213.

The flow path 1215 is formed inside the support mechanism portion 1213, and includes a refrigerant such as cooling water inside. For example, the flow path 1215 is formed so as to orbit the inside of the support mechanism portion 1213 so that the refrigerant can continuously circulate inside the support mechanism portion 1213.

The micropump 1216 circulates the refrigerant in the flow path 1215. For example, the micropump 1216 is mounted on the DAS substrate 1212 and operates by feeding power from the DAS substrate 1212.

Further, in the present embodiment, the processing circuit 122 has an acquisition function 1221 and a control function 1222. Here, the acquisition function 1221 is an example of an acquisition unit. Further, the control function 1222 is an example of a control unit.

The acquisition function 1221 acquires the calorific value of each of the plurality of detector modules 121 included in the X-ray detector 12.

For example, the acquisition function 1221 acquires the calorific value in each of the plurality of detector modules 121 based on the measured temperature or the count rate (number of incident photons).

For example, the acquisition function 1221 may perform the detector module 121 by irradiating X-rays with the subject P placed on the top plate 33 before the main scan is performed or before the main scan is performed. Measure the temperature or count rate for each. Then, the acquisition function 1221 acquires the calorific value by deriving the calorific value from the measured temperature or the count rate for each detector module 121.

At this time, for example, the acquisition function 1221 actually measures the temperature for each detector module 121 by using the temperature sensors individually attached to each detector module 121. Alternatively, for example, the acquisition function 1221 actually measures the count rate for each detector module 121 based on the electric signal output from each detector module 121 when the X-ray is irradiated.

Further, for example, the acquisition function 1221 may acquire the calorific value in each of the plurality of detector modules 121 based on the temperature or the count rate predicted based on the scan conditions. Here, for example, the scan conditions include the tube voltage, the tube current, the scan site, the body thickness of the subject P, and the like.

For example, the acquisition function 1221 predicts the temperature or count rate of each detector module 121 when the main scan is executed, based on the scan conditions set for the main scan, before the main scan is performed. Then, the acquisition function 1221 acquires the calorific value by deriving the calorific value from the predicted temperature or the count rate for each detector module 121.

At this time, for example, the acquisition function 1221 has the scan conditions stored in the memory or the like in advance after the scan conditions for the main scan are set, and the detector modules 121 when the scan is executed under the scan conditions. The temperature is predicted for each detector module 121 by acquiring the temperature corresponding to the scan conditions for the main scan with reference to the information indicating the correspondence with the temperature. Alternatively, the acquisition function 1221 determines the temperature from the scan condition for the main scan according to a relational expression representing the relationship between the scan condition and the temperature of each detector module 121 when the scan is executed under the scan condition, which is defined in advance. By deriving the above, the temperature may be predicted for each detector module 121.

Alternatively, for example, the acquisition function 1221 counts the scan conditions stored in the memory or the like in advance after the scan conditions for the main scan are set, and the count of each detector module 121 when the scan is executed under the scan conditions. The count rate is predicted for each detector module 121 by acquiring the count rate corresponding to the scan conditions for the main scan with reference to the information indicating the correspondence relationship with the rate. Alternatively, the acquisition function 1221 can be used from the scan conditions for the main scan according to a predefined relational expression representing the relationship between the scan conditions and the count rate of each detector module 121 when the scan is executed under the scan conditions. By deriving the count rate, the count rate may be predicted for each detector module 121.

The control function 1222 controls the control amount of each detector module 121 with respect to the micropump 1216 based on the calorific value of each of the plurality of detector modules 121 acquired by the acquisition function 1221.

Specifically, the control function 1222 controls the control amount of each detector module 121 with respect to the micropump 1216 so that the temperature distribution among the plurality of detector modules 121 included in the X-ray detector 12 approaches uniformly. ..

For example, the control function 1222 compares the calorific value acquired by the acquisition function 1221 with the preset upper limit value for each detector module 121. Then, the control function 1222 controls the amount of heat generated by the detector module 121 with respect to the micropump 1216 so that the cooling of the detector module 121 is strengthened when there is a detector module 121 whose calorific value exceeds the upper limit. To control.

At this time, for example, the control function 1222 changes the flow rate of the refrigerant for each detector module 121 by controlling the control amount of each detector module 121 with respect to the micropump 1216. Alternatively, the control function 1222 may change the temperature and the flow velocity of the refrigerant for each detector module 121.

According to such a configuration, for example, when the heat generation amount in each detector module 121 is acquired by the acquisition function 1221 during the main scan, each detector is fed back by the control function 1222. Cooling of the module 121 will be performed. At this time, when the measured count rate is used by the acquisition function 1221, the actual measurement is performed because there is a time lag between the change in the count rate and the change in the temperature of the detector module 121. Cooling will be controlled earlier than when temperature is used. On the other hand, for example, when the heat generation amount in each detector module 121 is acquired by the acquisition function 1221 before the main scan is performed, the control function 1222 cools each detector module 121 by a feed-forward method. Will be.

Here, the processing circuit 122 described above is realized by, for example, a processor. In this case, the acquisition function 1221 and the control function 1222 included in the processing circuit 122 are stored in the memory mounted on the X-ray detector 12 in the form of a program that can be executed by a computer. Then, the processing circuit 122 realizes a function corresponding to each program by reading each program from the memory and executing the program. In other words, the processing circuit 44 in the state where each program is read out has each processing function shown in the processing circuit 44 of FIG.

FIG. 4 is a flowchart showing a processing procedure of processing performed by the processing circuit 122 according to the first embodiment.

For example, as shown in FIG. 4, the processing circuit 122 acquires the calorific value of each of the plurality of detector modules 121 included in the X-ray detector 12 (step S11). This step corresponds to the acquisition function 1221. For example, the processing circuit 122 executes this step by reading the program corresponding to the acquisition function 1221 from the memory and executing the program.

Subsequently, the processing circuit 122 controls the control amount of each detector module 121 with respect to the micropump 1216 based on the calorific value of each of the acquired plurality of detector modules 121 (step S12). This step corresponds to the control function 1222. For example, the processing circuit 122 executes this step by reading a program corresponding to the control function 1222 from the memory and executing the program.

As described above, in the first embodiment, each detector module 121 included in the X-ray detector 12 has a flow path 1215 having a refrigerant inside, and a micropump 1216 that circulates the refrigerant in the flow path 1215. And prepare.

According to this configuration, an independent cooling circuit is provided for each detector module 121, and the cooling of the detector module 121 can be controlled for each module.

Further, in the first embodiment, the acquisition function 1221 included in the processing circuit 122 acquires the amount of heat generated in each of the plurality of detector modules 121 included in the X-ray detector 12. Then, the control function 1222 of the processing circuit 122 controls the control amount of each detector module 121 with respect to the micropump 1216 based on the calorific value of each of the plurality of detector modules 121 acquired by the acquisition function 1221.

According to this configuration, the temperature distribution among the plurality of detector modules 121 can be optimized by appropriately controlling the cooling for each detector module 121.

Therefore, according to the first embodiment, it is possible to prevent deterioration of the image quality of the captured image and failure of the detector module 121 caused by insufficient cooling of some of the detector modules 121. Further, it becomes unnecessary to provide a large-scale system for cooling the detector module 121, and the cost of the X-ray detector 12 can be reduced.

(Second embodiment)
In the first embodiment described above, an example of circulating the refrigerant in each detector module 121 has been described, but the embodiment is not limited to this. For example, by circulating the refrigerant between the detector modules 121, each detector module 121 may be cooled more efficiently. Hereinafter, such an example will be described as a second embodiment. In the second embodiment, the points different from the first embodiment will be mainly described, and detailed description of the contents common to the first embodiment will be omitted.

In this embodiment, the X-ray detector 12 further includes a bypass flow path that connects the flow path 1215 between the plurality of detector modules 121.

Further, the acquisition function 1221 acquires the calorific value of each of the plurality of detector modules 121 included in the X-ray detector 12, as in the first embodiment.

Further, the control function 1222 controls the connection destination of the bypass flow path based on the amount of heat generated in each of the plurality of detector modules 121 acquired by the acquisition function 1221.

Specifically, the control function 1222 controls the connection destination of the bypass flow path so that the temperature distribution among the plurality of detector modules 121 approaches uniformly.

For example, the control function 1222 is a bypass flow so as to connect the flow path 1215 between the detector module 121 having the largest calorific value among the plurality of detector modules 121 and the detector module 121 having the smallest calorific value. Control the connection destination of the road.

FIG. 5 is a diagram showing an example of cooling control by the bypass flow path and the control function 1222 according to the second embodiment.

For example, as shown in FIG. 5, a fixed bypass flow path 123 for connecting the flow path 1215 of each detector module 121 is provided for each predetermined set of detector modules 121. In this case, for example, the control function 1222 compares the calorific value of each detector module 121 with the upper limit value for each set of detector modules 121 connected by the bypass flow path 123. Then, the control function 1222 is a flow path of the detector module 121 when the calorific value of one of the detector modules 121 of the set of the detector modules 121 connected by the bypass flow path 123 exceeds the upper limit value. The connection destination of the bypass flow path is controlled so as to connect the 1215 and the flow path 1215 of the other detector module 121.

In this case, for example, the set of detector modules 121 connected by the bypass flow path 123 is fixedly set in advance according to the tendency of the temperature rise of each detector module 121.

Alternatively, for example, the control function 1222 may dynamically set the combination of the detector modules 121 connected by the bypass flow path 123 according to the scan conditions for the main scan. For example, when the scan site is the heart, the heart is placed near the center of the FOV (Field Of View), so that the subject P is biased to one of the channel directions with respect to the X-ray detector 12. Will be done. Therefore, for example, when the scan site is the heart, the control function 1222 has a detector module 121 arranged on one side in the channel direction and a detector module arranged on the other side in the X-ray detector 12. The bypass flow path 123 is set so as to connect to 121. On the other hand, in the case of a scan site where the subject P is placed near the center of the channel direction with respect to the X-ray detector 12, the control function 1222 is located near the center of the channel direction in the X-ray detector 12. The bypass flow path 123 is set so as to connect the detector module 121 arranged in and the detector module 121 arranged outside.

Alternatively, for example, the control function 1222 of the subject P taken by the X-ray CT device 1 or a camera or the X-ray CT device 1 installed in the X-ray CT device 1 or the imaging room after the subject P is placed on the top plate 33. An image may be acquired and the bypass flow path 123 may be set based on the acquired image. For example, the control function 1222 identifies the position of the subject P in the channel direction with respect to the X-ray detector 12 by using the image of the subject P, and has a detector module 121 arranged at a position overlapping the subject P. The bypass flow path 123 is set so as to connect the detector module 121 arranged at a position not overlapping with the test pair P.

FIG. 6 is a diagram showing another example of cooling control by the bypass flow path and the control function 1222 according to the second embodiment.

Alternatively, for example, as shown in FIG. 6, a variable bypass flow is provided so that the flow path 1215 of the detector module 121 can be connected to all the detector modules 121 included in the X-ray detector 12 in any combination. Road 123 is provided. In this case, for example, the control function 1222 compares the heat generation amount for each detector module 121 with the upper limit value for all the detector modules 121 included in the X-ray detector 12. Then, when there is a detector module 121 whose calorific value exceeds the upper limit value, the control function 1222 has a flow path 1215 of the detector module 121 and a flow of the detector module 121 having the smallest calorific value at that time. The connection destination of the bypass flow path is controlled so as to connect to the road 1215.

Here, as in the first embodiment, the processing circuit 122 is realized by, for example, a processor. In this case, the acquisition function 1221 and the control function 1222 included in the processing circuit 122 are stored in the memory mounted on the X-ray detector 12 in the form of a program that can be executed by a computer. Then, the processing circuit 122 realizes a function corresponding to each program by reading each program from the memory and executing the program. In other words, the processing circuit 44 in the state where each program is read out has each processing function shown in the processing circuit 44 of FIG.

FIG. 7 is a flowchart showing a processing procedure of processing performed by the processing circuit 122 according to the second embodiment.

For example, as shown in FIG. 7, the processing circuit 122 acquires the calorific value of each of the plurality of detector modules 121 included in the X-ray detector 12 (step S21). This step corresponds to the acquisition function 1221. For example, the processing circuit 122 executes this step by reading a program corresponding to the acquisition function 1221 from the memory and executing the program.

Subsequently, the processing circuit 122 controls the connection destination of the bypass flow path 123 based on the amount of heat generated in each of the plurality of detector modules 121 acquired by the acquisition function 1221 (step S22). This step corresponds to the control function 1222. For example, the processing circuit 122 executes this step by reading a program corresponding to the control function 1222 from the memory and executing the program.

As described above, in the second embodiment, the X-ray detector 12 further comprises a bypass flow path connecting the flow path 1215 between the plurality of detector modules 121.

According to this configuration, as in the first embodiment, the cooling of the detector module 121 can be controlled for each module, and the refrigerant is also circulated between the detector modules 121 to allow each detector module 121 to flow. Can be cooled more efficiently.

Further, in the second embodiment, the acquisition function 1221 of the processing circuit 122 acquires the calorific value of each of the plurality of detector modules 121 included in the X-ray detector 12. Then, the control function 1222 of the processing circuit 122 controls the connection destination of the bypass flow path 123 based on the calorific value in each of the plurality of detector modules 121 acquired by the acquisition function 1221.

According to this configuration, the heat dissipation area of the detector module 121, which has become hot, can be expanded by appropriately controlling the connection destination of the bypass flow path 123 according to the heat generation state of each detector module 121. Can be done. As a result, it is possible to suppress the temperature rise of each detector module 121 or accelerate the cooling of the detector module 121 which has become hot.

The control function 1222 may perform the cooling control described in the second embodiment in addition to the cooling control described in the first embodiment. In that case, the upper limit of the calorific value used in the first embodiment and the upper limit of the calorific value used in the second embodiment may be the same value or different values. .. For example, when the upper limit value is the same, the cooling control described in the first embodiment and the cooling control described in the second embodiment are started at the same time. On the other hand, when the upper limit value is set to a different value, if cooling is insufficient in one of the first embodiment and the second embodiment, the other cooling method is executed.

Further, in each of the above-described embodiments, an example in which the configurations of the detector module and the radiation detector disclosed in the present application are applied to the X-ray detector and the X-ray CT device has been described, but the embodiments are limited to this. do not have. For example, the configuration of the detector module and the radiation detector disclosed in the present application can be similarly applied to other radiation detectors and radiation diagnostic devices such as a γ-ray detector and a PET device.

Further, in each of the above-described embodiments, an example in which the acquisition unit and the control unit in the present specification are realized by the acquisition function 1221 and the control function 1222 of the processing circuit 122 has been described, but the embodiment is not limited to this. For example, the acquisition unit and the control unit in the present specification are realized by the acquisition function 1221 and the control function 1222 described in the embodiment, and are the same by hardware only, software only, or a mixture of hardware and software. It may be the one that realizes the function.

The word "processor" used in the above description is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an integrated circuit for a specific application (ASIC), or a programmable logic device. (For example, a circuit such as a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)) is meant. When the processor is, for example, a CPU, the processor realizes a function by reading and executing a program stored in a storage circuit. On the other hand, when the processor is, for example, an ASIC, the function is directly assembled as a logic circuit in the circuit of the processor instead of storing the program in the storage circuit. It should be noted that each processor of the present embodiment is not limited to the case where each processor is configured as a single circuit, and a plurality of independent circuits may be combined to form one processor to realize its function. good. Further, the plurality of components in FIG. 1 may be integrated into one processor to realize the function.

Further, in the above-described embodiments and modifications, each component of each of the illustrated devices is functionally conceptual, and does not necessarily have to be physically configured as shown in the figure. That is, the specific form of distribution or integration of each device is not limited to the one shown in the figure, and all or part of them may be functionally or physically dispersed or physically distributed in arbitrary units according to various loads and usage conditions. Can be integrated and configured. Further, each processing function performed by each device may be realized by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware by wired logic.

Further, among the processes described in the above-described embodiments and modifications, all or part of the processes described as being automatically performed can be manually performed, or can be performed manually. It is also possible to automatically perform all or part of the described processing by a known method. In addition, the processing procedure, control procedure, specific name, and information including various data and parameters shown in the above document and drawings can be arbitrarily changed unless otherwise specified.

According to at least one embodiment described above, the cooling of the detector module can be controlled for each module.

Although some embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other embodiments, and various omissions, replacements, changes, and combinations of embodiments can be made without departing from the gist of the invention. These embodiments and variations thereof are included in the scope of the invention described in the claims and the equivalent scope thereof, as are included in the scope and gist of the invention.

1 X-ray CT device 12 X-ray detector 121 Detector module 1215 Flow path 1216 Micropump 122 Processing circuit 1221 Acquisition function 1222 Control function 123 Bypass flow path

Claims (10)

A detector module having a plurality of detection elements for detecting radiation.
A flow path with a refrigerant inside and
A detector module including a circulation unit for circulating the refrigerant in the flow path. The detector module according to claim 1 is provided with a plurality of detector modules.
A bypass flow path for connecting the flow path between the plurality of detector modules is further provided.
Radiation detector. The detector module according to claim 1 is provided with a plurality of detector modules.
An acquisition unit that acquires the amount of heat generated in each of the plurality of detector modules,
A radiation detector further including a control unit that controls a control amount for the circulation unit of each detector module based on the calorific value. The control unit controls the control amount for the circulation unit of each detector module so that the temperature distribution among the plurality of detector modules approaches uniformly.
The radiation detector according to claim 3. The control unit changes the flow rate of the refrigerant for each detector module by controlling the control amount for the circulation unit of each detector module.
The radiation detector according to claim 3 or 4. An acquisition unit that acquires the amount of heat generated in each of the plurality of detector modules,
The radiation detector according to claim 2, further comprising a control unit that controls a connection destination of the bypass flow path based on the calorific value. The control unit controls the connection destination of the bypass flow path so that the temperature distribution between the plurality of detector modules approaches uniformly.
The radiation detector according to claim 6. The control unit connects the bypass flow path so as to connect the flow path between the detector module having the largest calorific value and the detector module having the smallest calorific value among the plurality of detector modules. Control the destination,
The radiation detector according to claim 6 or 7. The acquisition unit acquires the calorific value based on the measured temperature or count rate.
The radiation detector according to any one of claims 3 to 8. The acquisition unit acquires the calorific value based on the predicted temperature or count rate based on the scan conditions.
The radiation detector according to any one of claims 3 to 8.

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