PET (positron emission tomography) system correction method and device, computer equipment and storage medium

Abstract

The invention relates to a PET system correction method and device, computer equipment and a storage medium. The method comprises the steps of obtaining a target collection instruction; the target acquisition instruction is used for indicating that data acquisition of a current detection unit of the PET system is completed; controlling the scanning bed to move to the next detection unit of the PET system for data acquisition according to the target acquisition instruction, and correcting the PET system according to the scanning data of the current detection unit to obtain a correction result corresponding to the current detection unit; taking the next detection unit as a new current detection unit, and circularly executing the step of acquiring the target acquisition instruction until correction results of all the detection units are obtained; and obtaining a correction result of the PET system based on the correction results of all the detection units. According to the method, the data acquisition process and the data analysis process are strongly coupled, so that the system correction time can be shortened, and the system correction efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of medical imaging equipment, and in particular to a correction method, apparatus, computer equipment, and storage medium for a PET system. Background Art

[0002] Positron emission tomography (PET) is a medical imaging device used to examine the activity of organs and tissues within the body. Over time, PET systems can experience hardware degradation, leading to decreased performance. This necessitates on-site service engineers to perform active calibration on the PET system.

[0003] When the PET system is a PET system, it is usually necessary to perform multi-bed data acquisition on the PET system according to the length of the radiation source to achieve active correction of the PET system.

[0004] However, the traditional calibration process for PET systems has the problem of long calibration time. Summary of the Invention

[0005] Based on this, it is necessary to provide a PET system calibration method, device, computer equipment, computer-readable storage medium and computer program product that can shorten the calibration time of the PET system and improve the system calibration efficiency in order to address the above technical problems.

[0006] In a first aspect, the present application provides a calibration method for a PET system, wherein the PET system includes a scanning cavity and a scanning bed, wherein the scanning cavity includes a plurality of detection units arranged along an axial direction, and the scanning bed is capable of moving in and out of the scanning cavity along the axial direction. The method comprises:

[0007] Obtaining a target acquisition instruction; the target acquisition instruction is used to indicate that data acquisition of the current detection unit of the PET system has been completed;

[0008] Controlling the scanning bed to move to the next detection unit of the PET system to collect data according to the target acquisition instruction, and calibrating the current detection unit of the PET system according to the scan data of the current detection unit to obtain a calibration result of the current detection unit;

[0009] The next detection unit is used as the new current detection unit, and the step of obtaining the target acquisition instruction is executed cyclically until the calibration results of all the detection units are obtained; based on the calibration results of all the detection units, the calibration result of the PET system is obtained; wherein, the movement of the scanning bed to the next detection unit of the PET system is used to represent that the radiation source phantom set on the scanning bed moves to the preset position corresponding to the next detection unit.

[0010] In one embodiment, obtaining a calibration result of the PET system based on the calibration results of all detection units includes:

[0011] The calibration results of all detection units are statistically analyzed to obtain the calibration results of the PET system.

[0012] In one embodiment, the method further comprises:

[0013] When data acquisition of a current detection unit of the PET system is completed, obtaining scanning data of the PET system;

[0014] The scanning data of the PET system is screened for single event data of the current detection unit and / or coincident event data of the current detection unit to obtain the scanning data of the current detection unit.

[0015] In one embodiment, calibrating a current detection unit of a PET system according to scan data of the current detection unit to obtain a calibration result of the current detection unit includes:

[0016] Preprocessing the scan data of the current detection unit to obtain processed scan data of the current detection unit;

[0017] A preset correction algorithm is used to correct the current detection unit of the PET system according to the processed scan data of the current detection unit to obtain a correction result of the current detection unit.

[0018] In one embodiment, the scan data of the current detection unit includes single-event data, and a preset correction algorithm is used to calibrate the current detection unit of the PET system based on the processed scan data of the current detection unit to obtain a correction result for the current detection unit, including:

[0019] Using a position correction algorithm, the crystal position of the current detection unit of the PET system is corrected according to the processed scan data of the current detection unit to obtain an intermediate correction result;

[0020] An energy correction algorithm is used to perform energy correction on the current detection unit of the PET system according to the intermediate correction result and the processed scan data of the current detection unit to obtain a correction result of the current detection unit.

[0021] In one embodiment, the scan data of the current detection unit includes coincident event data, and a preset correction algorithm is used to calibrate the current detection unit of the PET system based on the processed scan data of the current detection unit to obtain a correction result for the current detection unit, including:

[0022] A preset correction algorithm is used to perform crystal position correction, energy correction, and flight time correction on the current detection unit of the PET system according to the processed scan data of the current detection unit to obtain a correction result of the current detection unit.

[0023] In one embodiment, the method further comprises:

[0024] Controlling the PET system to perform PET scanning on the object to be scanned, and obtaining scanning data of the object to be scanned;

[0025] Image reconstruction is performed based on the calibration results of the PET system and the scan data to obtain a PET image of the object to be scanned.

[0026] In a second aspect, the present application further provides a calibration device for a PET system, the PET system comprising a scanning chamber and a scanning bed, the scanning chamber comprising a plurality of detection units arranged along an axial direction, the scanning bed being capable of moving in and out of the scanning chamber along the axial direction, the device comprising:

[0027] An acquisition module is used to acquire a target acquisition instruction; the target acquisition instruction is used to indicate that data acquisition of the current detection unit of the PET system has been completed;

[0028] The correction module is configured to control the scanning bed to move to the next detection unit of the PET system for data acquisition according to the target acquisition instruction, and to calibrate the current detection unit of the PET system according to the scan data of the current detection unit to obtain a correction result of the current detection unit; use the next detection unit as the new current detection unit, and cyclically execute the step of obtaining the target acquisition instruction until the correction results of all detection units are obtained; and obtain the correction result of the PET system based on the correction results of all detection units; wherein the movement of the scanning bed to the next detection unit of the PET system is used to indicate that the radiation source phantom set on the scanning bed has moved to a preset position corresponding to the next detection unit.

[0029] In a third aspect, the present application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the PET system correction method in the first aspect are implemented.

[0030] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the correction method for the PET system in the first aspect.

[0031] In a fifth aspect, the present application further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps of the correction method for the PET system in the first aspect.

[0032] The PET system calibration method, apparatus, computer device, storage medium, and computer program product are applied to a PET system comprising a scanning chamber and a scanning bed. The scanning chamber comprises a plurality of detection units arranged along an axial direction, and the scanning bed is capable of moving in and out of the scanning chamber along the axial direction. In the process of using this method to calibrate a PET system in a medical scanning device, a target acquisition instruction indicating that data acquisition for a current detection unit of the PET system has been completed is obtained, and the scanning bed is controlled to move to the next detection unit of the PET system for data acquisition based on the target acquisition instruction. The current detection unit of the PET system is calibrated based on the scan data of the current detection unit to obtain a calibration result for the current detection unit. Subsequently, the next detection unit is used as the new current detection unit, and the step of obtaining the target acquisition instruction is repeatedly performed until calibration results for all detection units are obtained. A calibration result for the PET system is obtained based on the calibration results for all detection units. The movement of the scanning bed to the next detection unit of the PET system indicates that a radiation source phantom disposed on the scanning bed has moved to a preset position corresponding to the next detection unit.

[0033] It can be seen that, when the method proposed in the embodiment of the present application is used to calibrate the PET system, it is not the traditional method of first completing a multi-bed scan of the PET system, then fusing the scan data obtained from the multi-bed scan to obtain the scan data of the PET system, and then calibrating the PET system based on the scan data of the PET system; instead, when scanning the next detection unit of the PET system, the previous detection unit is synchronously calibrated based on the scan data collected by the previous detection unit; that is, the system correction workflow is optimized and adjusted in the present application, and the data acquisition process and the data analysis process are strongly coupled, that is, the data acquisition process and the data analysis process are executed in parallel, and the detection unit can be calibrated after the data of a detection unit is collected, without having to wait until the data of all detection units are collected before performing the correction operation, which can shorten the system correction time and improve the system correction efficiency.

[0034] In addition, data collection and data analysis processes are performed independently for each detection unit of the PET system, so that system correction is performed independently for each detection unit, rather than correcting the entire PET system based on the scanning data of the entire PET system. Therefore, the amount of data in the correction algorithm can be reduced, and while ensuring the accuracy of the correction, the correction efficiency of the system can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 A diagram illustrating an application environment of a calibration method for a PET system according to an embodiment;

[0037] Figure 2 FIG1 is a flow chart of a calibration method for a PET system according to an embodiment;

[0038] Figure 3 is a schematic flow chart of a calibration method for a PET system in another embodiment;

[0039] Figure 4 is a schematic flow chart of a calibration method for a PET system in another embodiment;

[0040] Figure 5 is a schematic structural diagram of a detection unit of a PET system in one embodiment;

[0041] Figure 6 is a schematic flow chart of a calibration method for a PET system in another embodiment;

[0042] Figure 7 is a structural block diagram of a correction device for a PET system in one embodiment;

[0043] Figure 8 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0045] Calibration and maintenance of PET systems are crucial components of daily use. Regular maintenance and servicing keep the system in optimal condition for patient imaging, resulting in high-quality PET scans. However, as PET system hardware degrades over time, performance degradation and other issues can occur. In these cases, a service engineer will be required to perform on-site active calibration of the PET system.

[0046] Generally speaking, for a long-axis PET system, since the long-axis PET system is composed of multiple detection units, during calibration, it is necessary to collect data from each detection unit to fully cover all crystal modules of the long-axis PET system in order to achieve accurate calibration of the system.

[0047] Traditionally, the system requires data collection from multiple beds (one bed corresponds to one detection unit) based on the length of the radiation source. After data collection is complete, the collected data is analyzed and the calibration algorithm is run based on the analyzed data to generate the results. However, this traditional calibration method is time-consuming.

[0048] Based on this, the present application proposes a correction method for a PET system, which improves and optimizes the traditional correction workflow by adopting a parallel accelerated workflow. By using this method, the correction algorithm can be called in parallel for each bed without waiting for the completion of data collection for all multiple beds, thereby speeding up the overall correction time, improving the correction efficiency of the PET system, and further improving the energy efficiency of service engineers.

[0049] The PET system calibration method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown, the medical scanning device 102 may include a PET device, a PET / CT device, a PET / MR device, or other PET devices, or an integrated PET device. It should be noted that the medical scanning device is equipped with a PET scanning system, referred to as a PET system.

[0050] For example, the medical scanning device may be an imaging scanner equipped with a long-axis scanning system. A long-axis scanning system is a scanning system with a large axial scanning field of view, capable of whole-body scanning, thereby providing high-quality, high-resolution scanned images. In contrast, a short-axis scanning system primarily scans localized areas of the human body, such as the brain, lungs, and abdomen, and provides relatively poor-quality scanned images.

[0051] In an exemplary embodiment, Figure 2 As shown, a correction method for a PET system is provided, which is applied to Figure 1Taking the medical scanning device in FIG. 1 as an example, the method includes the following steps 202 to 204. In which:

[0052] Step 202: Acquire a target acquisition instruction; the target acquisition instruction is used to indicate that data acquisition of the current detection unit of the PET system has been completed.

[0053] Long-axis PET systems typically need to be divided into multiple detection units. During system calibration, the scanning bed, on which the radiation source is placed, needs to be moved sequentially to each detection unit. When the radiation source is located in each detection unit, the control system is controlled to scan the radiation source separately, thereby obtaining scanning data for each detection unit and implementing multi-bed scanning. When the scanning bed is moved to each detection unit, the radiation source is moved to a preset position corresponding to each detection unit, such as the center position of each detection unit, by moving the scanning bed. In some implementations, the radiation source can also be moved to the center position of each detection unit by moving the radiation source relative to the scanning bed, thereby enabling data collection for each detection unit.

[0054] For example, during system calibration, the medical scanning device can obtain a system calibration instruction and determine multiple detection units based on the system calibration instruction. Then, based on the position of the radiation source, the scanning bed is controlled to move to the first detection unit. When the radiation source is located at the center position corresponding to the first detection unit, the PET system is controlled to scan the radiation source to obtain scanning data corresponding to the first detection unit. Then, after the scan of the first detection unit is completed, a target acquisition instruction can be sent to the PET system. The target acquisition instruction can be used to indicate that data acquisition for the first detection unit of the PET system has been completed. The target acquisition instruction can also be used to instruct data acquisition for the next detection unit of the PET system, i.e., the second detection unit. Using the same method, data is acquired for each detection unit of the PET system in sequence, thereby obtaining scanning data for each detection unit of the PET system.

[0055] Illustratively, the medical scanning device can perform system calibration on the PET system carried thereon according to a preset calibration cycle or a preset calibration time point; it can also automatically perform system calibration on the PET system after the medical scanning device is turned on; it can also perform system calibration on the PET system after obtaining a manual trigger from the user; for example: the medical scanning device can be set to perform a system calibration operation once a week, or the medical scanning device can be set to perform a system calibration operation before work every day, such as at 8 o'clock in the morning, or the medical scanning device can be set to perform a system calibration operation after it is turned on, etc.

[0056] In addition, when determining the multiple detection units corresponding to the PET system, the medical scanning device can divide the crystal module in the detector of the PET system according to the size of the radiation source to obtain multiple detection units; it can also divide the crystal module in the detector of the PET system according to the division parameters input by the user, such as the number of detection units, to obtain multiple detection units, etc.; in the embodiment of the present application, there is no specific limitation on the division method of the detection units and the number of divided detection units.

[0057] Step 204 : Control the scanning bed to move to the next detection unit of the PET system to collect data according to the target acquisition instruction, and calibrate the current detection unit of the PET system according to the scan data of the current detection unit to obtain a calibration result of the current detection unit.

[0058] The movement of the scanning bed to the next detection unit of the PET system is used to indicate that the radiation source phantom set on the scanning bed moves to a preset position corresponding to the next detection unit.

[0059] For example, after the PET system completes scanning of the current detection unit, the scanning bed can be controlled to move to the next detection unit in the PET system for data acquisition. Furthermore, the scan data of the current detection unit can be obtained and, based on the scan data of the current detection unit, the current detection unit of the PET system can be calibrated to obtain a calibration result for the current detection unit. In other words, during system calibration, the data acquisition process is coupled with the data analysis process. While data acquisition is ongoing, system calibration is performed on the corresponding detection unit in the PET system based on the acquired data, thereby reducing system calibration time and improving system calibration efficiency.

[0060] For example, when calibrating the PET system based on the scan data of the current detection unit, each crystal module within the current detection unit of the PET system may be calibrated, and calibration results for each crystal module within the current detection unit may be obtained. For example, if the PET system is a long-axis PET system, during system calibration, the position of each crystal module, the energy of each crystal module, and the time of flight of each crystal module may be corrected.

[0061] Step 206: Use the next detection unit as a new current detection unit and loop through the steps of obtaining the target acquisition instruction until calibration results of all detection units are obtained; based on the calibration results of all detection units, a calibration result of the PET system is obtained.

[0062] That is to say, by adopting the above-mentioned parallel processing operation, data collection and correction operations can be performed on each detection unit in turn, thereby obtaining correction results of all detection units.

[0063] Furthermore, when the calibration results of each detection unit of the PET system are obtained, the calibration results of the PET system can be obtained based on the calibration results of each detection unit of the PET system; for example, the calibration results of each detection unit can be fused to obtain the calibration result of the PET system.

[0064] The above-mentioned PET system calibration method can be applied to a PET system including a scanning cavity and a scanning bed. The scanning cavity includes multiple detection units arranged in an axial direction, and the scanning bed can move in and out of the scanning cavity in the axial direction. When using this method to calibrate a PET system in a medical scanning device, a target acquisition instruction indicating that data acquisition for a current detection unit of the PET system has been completed is obtained, and the scanning bed is controlled to move to the next detection unit of the PET system for data acquisition according to the target acquisition instruction. The current detection unit of the PET system is calibrated based on the scan data of the current detection unit to obtain a calibration result for the current detection unit. Then, the next detection unit is used as the new current detection unit, and the step of obtaining the target acquisition instruction is repeatedly performed until calibration results for all detection units are obtained. The calibration result of the PET system is obtained based on the calibration results of all detection units. The movement of the scanning bed to the next detection unit of the PET system indicates that a radiation source phantom disposed on the scanning bed has moved to a preset position corresponding to the next detection unit.

[0065] It can be seen that, when the method proposed in the embodiment of the present application is used to calibrate the PET system, it is not the traditional method of first completing a multi-bed scan of the PET system, then fusing the scan data obtained from the multi-bed scan to obtain the scan data of the PET system, and then calibrating the PET system based on the scan data of the PET system; instead, when scanning the next detection unit of the PET system, the previous detection unit is synchronously calibrated based on the scan data collected by the previous detection unit; that is, the system correction workflow is optimized and adjusted in the present application, and the data acquisition process and the data analysis process are strongly coupled, that is, the data acquisition process and the data analysis process are executed in parallel, and the detection unit can be calibrated after the data of a detection unit is collected, without having to wait until the data of all detection units are collected before performing the correction operation, which can shorten the system correction time and improve the system correction efficiency.

[0066] In addition, data collection and data analysis processes are performed independently for each detection unit of the PET system, so that system correction is performed independently for each detection unit, rather than correcting the entire PET system based on the scanning data of the entire PET system. Therefore, the amount of data in the correction algorithm can be reduced, and while ensuring the accuracy of the correction, the correction efficiency of the system can be further improved.

[0067] In an exemplary embodiment, during the execution of the loop operation in step 206, when a target instruction is received, it can be determined based on the target acquisition instruction whether the current detection unit is the last detection unit to be scanned in the PET system. If the current detection unit is not the last detection unit to be scanned in the PET system, the scanning bed can be controlled to move to the next detection unit of the PET system for data acquisition, and the current detection unit of the PET system can be calibrated based on the scan data of the current detection unit to obtain a calibration result for the current detection unit.

[0068] When the current detection unit is the last detection unit to be scanned by the PET system, the scanning bed may not be controlled. Alternatively, the scanning bed may be controlled to move to a target position, which may be the original position of the scanning bed, that is, the position of the scanning bed before imaging scanning. At the same time, the current detection unit of the PET system may be calibrated based on the scanning data of the current detection unit (that is, the last detection unit) to obtain a calibration result for the current detection unit.

[0069] That is, during the process of sequentially acquiring data from each detection unit of the PET system, each time data acquisition for the next detection unit is performed, it is necessary to first determine whether the current detection unit, for which data acquisition has already been completed, is the last detection unit to be scanned in the PET system. If the current detection unit is not the last detection unit to be scanned, it indicates that there are detection units that have not yet been scanned. In this case, the scanning of the detection unit next to the current detection unit is continued, and the calibration operation of the current detection unit is simultaneously performed. This process is repeated to ensure that the calibration operation of the previous detection unit can be performed simultaneously with the scanning of the next detection unit. For example, when scanning the second detection unit, the calibration operation is performed on the first detection unit; when scanning the third detection unit, the calibration operation is performed on the second detection unit; when scanning the fourth detection unit, the calibration operation is performed on the third detection unit, and so on.

[0070] When the current detection unit that has completed data acquisition is the last detection unit to be scanned in the PET system, it means that all detection units of the PET system have completed the data acquisition operation. At this time, the data acquisition task can be ended; at the same time, when the current detection unit completes data acquisition, the current detection unit of the PET system can be calibrated based on the scanning data of the current detection unit. After the calibration is completed, the calibration result corresponding to the last detection unit of the PET system can be obtained.

[0071] Furthermore, after completing data acquisition and calibration for all detection units of the PET system, calibration results corresponding to each detection unit of the PET system can be obtained, and the calibration results corresponding to each detection unit can be statistically analyzed to obtain the calibration result corresponding to the entire PET system. For example, the calibration results of each detection unit of the PET system can be statistically fused to obtain the final calibration result corresponding to the entire PET system. For example, if the PET system includes a first detection unit, a second detection unit, and a third detection unit, the calibration results of the first detection unit, the second detection unit, and the third detection unit can be combined to obtain the calibration result of the PET system.

[0072] In this embodiment, during multi-bed scanning of a PET system, each detection unit of the PET system is scanned sequentially, and while scanning each detection unit, system calibration is simultaneously performed on the previous detection unit. Specifically, if it is determined that the current detection unit for which data acquisition has completed is not the last detection unit to be scanned, data acquisition continues for the detection unit next to the current detection unit, and system calibration is simultaneously performed on the current detection unit. If it is determined that the current detection unit for which data acquisition has completed is the last detection unit to be scanned, data acquisition for all detection units of the PET system has been completed, and only the last detection unit needs to be calibrated based on the scan data obtained from the last scan. Finally, the calibration results of each detection unit are statistically analyzed to obtain the final calibration result of the entire PET system. This method allows for simultaneous multi-bed data acquisition of the PET system and detection unit calibration based on the acquired data, without having to wait for data acquisition of all detection units to be completed before performing calibration operations for the entire system. This shortens system calibration time and improves system calibration efficiency.

[0073] In an exemplary embodiment, Figure 3 As shown, the above step 204 involves the scanning data of the current detection unit. The acquisition method of the scanning data of the current detection unit may include steps 302 to 304.

[0074] Step 302: After completing data acquisition of the current detection unit of the PET system, obtain scanning data of the PET system.

[0075] Typically, when performing multi-bed scanning on a PET system, the scanning bed can move the radiation source to the position corresponding to a detection unit in the PET system, thereby scanning that detection unit. It should be noted that when scanning a detection unit, the PET system is controlled to scan the radiation source. Based on the line of response (LOR) connecting the photon pairs detected by the detector, not only will the crystal module in the corresponding detection unit of the PET system receive the radiation source's scanning data, but the crystal modules in other detection units will also receive the radiation source's scanning data.

[0076] In addition, each crystal module can not only receive single event data from the radiation source, but the corresponding detector crystal module can also receive coincident event data emitted 180° from each other generated by an annihilation event.

[0077] Step 304 : Screen the scan data of the PET system for single event data of the current detection unit and / or coincident event data of the current detection unit to obtain scan data of the current detection unit.

[0078] Among them, the scanning data of the current detection unit may include the single event data of each crystal module in the current detection unit, and / or the coincidence event data of each crystal module in the current detection unit; that is, when performing system correction, the system correction can be performed based on the single event data of each crystal module, or based on the coincidence event data of each crystal module, or a comprehensive system correction can be performed by combining the single event data and coincidence event data of each crystal module.

[0079] Based on this, for each detection unit, when the scanning data of all crystal modules in the PET system is obtained, the scanning data corresponding to the current detection unit can be filtered out from the scanning data, including the single event data of the current detection unit and / or the coincident event data of the current detection unit; in actual applications, it can be determined according to specific correction requirements whether the data required for correction is single event data, coincident event data, or single event data and coincident event data, and then the required correction data corresponding to the current detection unit can be filtered out from the scanning data.

[0080] In this embodiment, after completing data acquisition for the current detection unit of the PET system, scan data of the PET system is acquired, and the scan data of the PET system is filtered for single event data and / or consistent event data of the current detection unit to obtain scan data of the current detection unit. Specifically, when performing system calibration on the current detection unit of the PET system based on the scan data of the current detection unit, it is necessary to first filter the scan data corresponding to the current detection unit from the scan data of all detection units of the PET system. Only then can calibration of the current detection unit be performed based on the scan data of the current detection unit, thereby improving the accuracy of local calibration of the PET system.

[0081] In an exemplary embodiment, Figure 4 As shown, in the above step 204, the PET system is calibrated according to the scan data of the current detection unit to obtain the calibration result corresponding to the current detection unit, which may include steps 402 to 404.

[0082] Step 402 : pre-process the scan data of the current detection unit to obtain processed scan data of the current detection unit.

[0083] Exemplarily, when scanning data corresponding to the current detection unit is screened from scanning data of all detection units comprising the PET system, before calibrating the current detection unit of the PET system based on the scanning data of the current detection unit, relevant preprocessing operations may be performed on the scanning data of the current detection unit to obtain scanning data that meets preset conditions, thereby improving the system calibration efficiency and accuracy. Exemplarily, the preset conditions may include, but are not limited to, processing conditions related to data quality, processing conditions related to data format, etc. Accordingly, the preprocessing operations may include, but are not limited to, one or more data processing operations related to data quality, one or more data processing operations related to data format, etc.; for example, performing noise reduction, averaging, smoothing, interpolation, format conversion, etc. on the scanning data; the specific implementation of the preprocessing operations is not specifically limited in the embodiments of the present application.

[0084] Step 404 : Using a preset correction algorithm, calibrate the current detection unit of the PET system according to the processed scan data of the current detection unit to obtain a correction result of the current detection unit.

[0085] For single event data and coincidence event data, the preset correction algorithms used by the two may be different, that is, single event data has a corresponding correction algorithm, and coincidence event data has a corresponding correction algorithm.

[0086] For example, when the scan data of the current detection unit includes single-event data, a position correction algorithm can be first employed to perform crystal position correction on the current detection unit of the PET system based on the processed scan data of the current detection unit, thereby obtaining an intermediate correction result. Subsequently, an energy correction algorithm can be employed to perform energy correction on the current detection unit of the PET system based on the intermediate correction result and the processed scan data of the current detection unit, thereby obtaining a correction result for the current detection unit. In other words, the correction algorithm corresponding to the single-event data can include a position correction algorithm and an energy correction algorithm. First, based on the position correction algorithm and the single-event data of the current detection unit, position correction is performed on each crystal module within the current detection unit. Subsequently, based on the energy correction algorithm, the single-event data of the current detection unit, and the position correction result, energy correction is performed on each crystal module within the current detection unit, thereby obtaining a correction result for the current detection unit. The correction result for the current detection unit can include correction results for each crystal module within the current detection unit.

[0087] For example, when the scan data of the current detection unit includes coincidence event data, a preset correction algorithm can be used to perform crystal position correction, energy correction, and time-of-flight correction on the current detection unit of the PET system based on the processed scan data of the current detection unit, thereby obtaining a correction result for the current detection unit. In other words, for coincidence events, a comprehensive correction algorithm can be used to comprehensively correct the crystal position, energy, and time-of-flight of the current detection unit of the PET system.

[0088] In this embodiment, the scan data of the current detection unit is first preprocessed to obtain processed scan data of the current detection unit. Then, a preset correction algorithm is used to calibrate the current detection unit of the PET system based on the processed scan data of the current detection unit to obtain a correction result for the current detection unit. That is, in this embodiment, before calibrating the current detection unit based on the scan data of the current detection unit, the acquired scan data of the current detection unit is first preprocessed. Then, the current detection unit is calibrated based on the preprocessed scan data corresponding to the current detection unit. This method can improve the accuracy of local calibration of the PET system.

[0089] The following describes the calibration method of the PET system in detail in combination with specific application scenarios. Take the medical system including the PET system as an example, the PET system includes a long-axis PET system, and the long-axis PET system includes three detection units (such as Figure 5 For the cases of U0, U1, and U2 shown in FIG, calibration of a long-axis PET system may include the following steps:

[0090] Step 1: Control the scanning bed to move to the U0 detection unit of the long-axis PET system, and collect scanning data corresponding to the U0 detection unit.

[0091] The scanning data corresponding to the U0 detection unit may include single event data within the U0 detection unit and / or coincidence event data within the U0 detection unit. For example, scanning data of each crystal module within the detector can be obtained after the PET system scans the radiation source; then, the scanning data corresponding to each crystal module within the U0 detection unit is filtered out from the scanning data. The coincidence event data within the U0 detection unit may include coincidence event data U0-U0 within U0, coincidence event data U0-U1 between U0 and U1, and coincidence event data U0-U2 between U0 and U2.

[0092] In addition, the scanning bed moves to the U0 detection unit of the long-axis PET system, which means that the radiation source on the scanning bed moves to the middle position of the U0 detection unit.

[0093] Step 2: After the data acquisition of the U0 detection unit is completed, the scanning bed is controlled to move to the U1 detection unit of the long-axis PET system and the scanning data corresponding to the U1 detection unit is acquired. At this time, the step of calibrating the U0 detection unit of the long-axis PET system based on the scanning data corresponding to the U0 detection unit and obtaining the calibration result of the U0 detection unit is performed in parallel.

[0094] Step 3: After the data acquisition of the U1 detection unit is completed, the scanning bed is controlled to move to the U2 detection unit of the long-axis PET system and the scanning data corresponding to the U2 detection unit is acquired. At this time, the step of calibrating the U1 detection unit of the long-axis PET system based on the scanning data corresponding to the U1 detection unit and obtaining the calibration result of the U1 detection unit is performed in parallel.

[0095] It should be noted that when the time consumed by the data acquisition and correction processes is different, if the data acquisition of the U1 detection unit is completed, the correction process of the U0 detection unit has not yet ended. At this time, the data acquisition process of the U2 detection unit can continue to be executed, and the correction process of the U1 detection unit can be executed after the correction process of the U0 detection unit is completed.

[0096] Step 4: After the data acquisition of the U2 detection unit is completed and the calibration process of the U1 detection unit is finished, the U2 detection unit of the long-axis PET system is calibrated based on the scanning data corresponding to the U2 detection unit, and the calibration result of the U2 detection unit is obtained.

[0097] Step 5: Combine the correction result of the U0 detection unit, the correction result of the U1 detection unit, and the correction result of the U2 detection unit to obtain the correction result corresponding to the long-axis PET system.

[0098] In an exemplary embodiment, after the PET system is calibrated, an imaging scan of the object to be scanned can be performed based on the calibrated PET system; Figure 6 As shown, the above method may further include steps 602 to 604, wherein.

[0099] Step 602: Control the PET system to perform a PET scan on the object to be scanned, and obtain scan data of the object to be scanned.

[0100] Step 604 : Perform image reconstruction based on the calibration result of the PET system and the scan data to obtain a PET image of the object to be scanned.

[0101] For example, after the PET system is calibrated, the calibration results of the PET system can be stored in the PET system in the form of a configuration file, which includes parameter information such as the position, flight time, and energy of each crystal module of the detector; based on the parameters in the configuration file, the scanning data of the PET scan of the object to be scanned through the PET system can be reconstructed to obtain a PET image of the object to be scanned.

[0102] In this embodiment, the quality of the PET scan image can be improved by performing PET imaging scans using the calibrated PET system.

[0103] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0104] Based on the same inventive concept, embodiments of the present application further provide a PET system calibration device for implementing the aforementioned PET system calibration method. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more PET system calibration device embodiments provided below can be found in the aforementioned limitations of the PET system calibration method and are not further elaborated here.

[0105] In an exemplary embodiment, Figure 7As shown, a correction device for a PET system is provided. The PET system includes a scanning cavity and a scanning bed. The scanning cavity includes multiple detection units arranged in an axial direction. The scanning bed can move in and out of the scanning cavity in the axial direction. The device includes: an acquisition module 702 and a correction module 704, wherein:

[0106] The acquisition module 702 is used to acquire a target acquisition instruction; the target acquisition instruction is used to indicate that data acquisition of the current detection unit of the PET system has been completed.

[0107] The calibration module 704 is configured to control the movement of the scanning bed to the next detection unit of the PET system for data acquisition according to the target acquisition instruction, and to calibrate the PET system based on the scan data of the current detection unit to obtain a calibration result corresponding to the current detection unit. The next detection unit is used as the new current detection unit, and the steps of obtaining the target acquisition instruction are repeatedly executed until calibration results for all detection units are obtained. The calibration result of the PET system is obtained based on the calibration results of all detection units. The movement of the scanning bed to the next detection unit of the PET system indicates that the radiation source phantom disposed on the scanning bed has moved to a preset position corresponding to the next detection unit.

[0108] In one embodiment, the correction module 704 is specifically configured to perform statistical analysis on the correction results of all detection units to obtain a correction result of the PET system.

[0109] In one embodiment, the apparatus further comprises:

[0110] an acquisition module, configured to acquire scan data of the PET system upon completion of data acquisition of a current detection unit of the PET system;

[0111] The screening module is used to screen the scanning data of the PET system for single event data of the current detection unit and / or coincident event data of the current detection unit to obtain the scanning data of the current detection unit.

[0112] In one embodiment, the correction module 704 includes:

[0113] A preprocessing unit, configured to preprocess the scan data of the current detection unit to obtain processed scan data of the current detection unit;

[0114] The correction unit is used to calibrate the current detection unit of the PET system according to the processed scan data of the current detection unit using a preset correction algorithm to obtain a correction result of the current detection unit.

[0115] In one embodiment, the scanning data of the current detection unit includes single event data, and the correction unit is used to use a position correction algorithm to perform crystal position correction on the current detection unit of the PET system according to the processed scanning data of the current detection unit to obtain an intermediate correction result; and use an energy correction algorithm to perform energy correction on the current detection unit of the PET system according to the intermediate correction result and the processed scanning data of the current detection unit to obtain a correction result of the current detection unit.

[0116] In one embodiment, the scanning data of the current detection unit includes coincident event data, and the correction unit is used to use a preset correction algorithm to perform crystal position correction, energy correction, and flight time correction on the current detection unit of the PET system based on the processed scanning data of the current detection unit to obtain a correction result of the current detection unit.

[0117] In one embodiment, the apparatus further comprises:

[0118] A scanning module, used to control the PET system to perform PET scanning on the object to be scanned, and obtain scanning data of the object to be scanned;

[0119] The reconstruction module is used to perform image reconstruction based on the calibration results of the PET system and the scanning data to obtain a PET image of the object to be scanned.

[0120] Each module in the aforementioned PET system calibration device may be implemented in whole or in part via software, hardware, or a combination thereof. Each module may be embedded in or independent of a processor within a computer device in the form of hardware, or may be stored in a computer device memory in the form of software, allowing the processor to call and execute the corresponding operations of each module.

[0121] In an exemplary embodiment, a computer device is provided. The computer device may be a medical scanning device, and its internal structure diagram may be as shown in FIG. Figure 8As shown. The computer device includes a processor, a memory, an input / output interface (I / O) and a communication interface. The processor, memory and input / output interface are connected via a system bus, and the communication interface is connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The database of the computer device is used to store scan data of each detection unit of the medical system collected when calibrating the medical system. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, a calibration method for a PET system is implemented.

[0122] Those skilled in the art will understand that Figure 8 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0123] In an exemplary embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps of the PET system calibration method in any of the above embodiments when executing the computer program.

[0124] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the PET system calibration method in any of the above embodiments are implemented.

[0125] In one embodiment, a computer program product is provided, comprising a computer program, which implements the steps of the PET system calibration method in any of the above embodiments when executed by a processor.

[0126] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0127] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processors (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), data analysis logic devices based on quantum computing, and the like.

[0128] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0129] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A calibration method for a PET system, wherein the PET system comprises a scanning chamber and a scanning bed, wherein the scanning chamber comprises a plurality of detection units arranged along an axial direction, and the scanning bed is capable of moving in and out of the scanning chamber along the axial direction, wherein: The method comprises: Obtaining a target acquisition instruction; the target acquisition instruction is used to indicate that data acquisition of a current detection unit of the PET system has been completed; controlling the scanning bed to move to the next detection unit of the PET system to acquire data according to the target acquisition instruction, and calibrating the current detection unit of the PET system according to the scan data of the current detection unit to obtain a calibration result of the current detection unit; The next detection unit is used as a new current detection unit, and the step of obtaining the target acquisition instruction is executed cyclically until calibration results of all detection units are obtained; a calibration result of the PET system is obtained based on the calibration results of all detection units; wherein, the movement of the scanning bed to the next detection unit of the PET system is used to indicate that a radiation source phantom disposed on the scanning bed has moved to a preset position corresponding to the next detection unit.

2. The method according to claim 1, characterized in that The step of obtaining a calibration result of the PET system based on the calibration results of all the detection units includes: Statistical analysis is performed on the calibration results of all the detection units to obtain a calibration result of the PET system.

3. The method according to claim 1, characterized in that The method further comprises: When data acquisition of a current detection unit of the PET system is completed, acquiring scanning data of the PET system; The scanning data of the PET system is screened for single event data of the current detection unit and / or coincident event data of the current detection unit to obtain the scanning data of the current detection unit.

4. The method according to claim 1, wherein The step of calibrating the current detection unit of the PET system according to the scan data of the current detection unit to obtain a calibration result of the current detection unit includes: Preprocessing the scan data of the current detection unit to obtain processed scan data of the current detection unit; A preset correction algorithm is used to correct the current detection unit of the PET system according to the processed scan data of the current detection unit to obtain a correction result of the current detection unit.

5. The method according to claim 4, characterized in that The scan data of the current detection unit includes single event data. The current detection unit of the PET system is calibrated according to the processed scan data of the current detection unit using a preset correction algorithm to obtain a correction result of the current detection unit, including: Using a position correction algorithm, performing crystal position correction on the current detection unit of the PET system according to the processed scan data of the current detection unit to obtain an intermediate correction result; An energy correction algorithm is used to perform energy correction on the current detection unit of the PET system according to the intermediate correction result and the processed scan data of the current detection unit to obtain a correction result of the current detection unit.

6. The method according to claim 4, characterized in that The scan data of the current detection unit includes coincidence event data, and the current detection unit of the PET system is calibrated according to the processed scan data of the current detection unit using a preset correction algorithm to obtain a correction result of the current detection unit, including: A preset correction algorithm is used to perform crystal position correction, energy correction, and flight time correction on the current detection unit of the PET system according to the processed scan data of the current detection unit to obtain a correction result of the current detection unit.

7. The method according to any one of claims 1 to 6, characterized in that The method further comprises: Controlling the PET system to perform a PET scan on the object to be scanned to obtain scan data of the object to be scanned; Image reconstruction is performed based on the calibration result of the PET system and the scan data to obtain a PET image of the object to be scanned.

8. A calibration device for a PET system, the PET system comprising a scanning chamber and a scanning bed, the scanning chamber comprising a plurality of detection units arranged along an axial direction, the scanning bed being capable of moving in and out of the scanning chamber along the axial direction, characterized in that: The device comprises: an acquisition module, configured to acquire a target acquisition instruction; the target acquisition instruction is used to indicate that data acquisition of a current detection unit of the PET system has been completed; a correction module, configured to control the scanning bed to move to the next detection unit of the PET system for data acquisition according to the target acquisition instruction, and to calibrate the current detection unit of the PET system according to the scan data of the current detection unit to obtain a correction result of the current detection unit; use the next detection unit as the new current detection unit, and repeatedly execute the step of obtaining the target acquisition instruction until the correction results of all detection units are obtained; and obtain the correction result of the PET system based on the correction results of all detection units; wherein, the movement of the scanning bed to the next detection unit of the PET system is used to indicate that the radiation source phantom set on the scanning bed has moved to a preset position corresponding to the next detection unit.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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