Method for real-time correction of a PET system based on real-time clinical scan data

Abstract

The present invention relates to a method for real-time calibration of a PET system based on real-time clinical scan data, and the method includes: obtaining real-time clinical scan data; wherein, the real-time clinical scan data is data during the acquisition process of a patient's PET image, and the real-time clinical scan data includes position information, energy information, and time information; performing statistical analysis on the energy information and / or time information of each PET detector of the PET system based on the position information to obtain real-time characteristic data of each crystal interval in a set crystal interval on each PET detector; calculating real-time calibration parameters for each crystal interval based on the real-time characteristic data of each crystal interval; and performing real-time calibration on the PET system by using the real-time calibration parameters to ensure that the PET system is in an ideal working state. The present invention can optimize the state of the system in real time and accurately, reduce the radiation dose received by operators, reduce the maintenance cost of institutional radiation sources, and increase the effective duration of the PET system available for clinical scans.

Description

Technical Field

[0001] The present invention relates to the technical field of radiation detection and the field of medical imaging, and particularly to a method for real-time calibration of a PET system based on real-time clinical scan data. Background Art

[0002] In order to reduce the influence of the energy / time performance change of a PET system on a Positron Emission Tomography (PET) system, traditional processing solutions are all based on the idea of quality control. For example, by ensuring the stability of the system working temperature as much as possible, the influence brought by the temperature effect of the scintillator and the circuit can be reduced; for another example, electronic devices with good long-term stability are selected to reduce the instability influence brought by the fluctuation of the electronic devices; for another example, based on the stability of the system, the debugging and calibration period of the system is determined to ensure the stability of the system working within this period range, which is the conventional operation quality control scheme of PET products.

[0003] However, the above operation quality control schemes are all carried out when the PET system is in a non-working state. Traditional quality control uses a dedicated solid-state radiation source, which requires the maintenance and operation of the radiation source; there is also the use of the background radiation of the detector, which takes a long time and it is difficult to obtain a high-precision statistic. The debugging and calibration of the PET system during the quality control process have to be carried out by specifically setting aside time before the clinical scan, which will thus compress the clinical scan time of the PET system. At the same time, the changes in the environment and hardware during the clinical scan cannot be compensated in real time, and timely and accurate system imaging quality control cannot be obtained. Summary of the Invention

[0004] (1) Technical Problems to be Solved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a method for real-time calibration of a PET system based on real-time clinical scan data, so as to solve the problems existing in the prior art such as the non-real-time calibration of PET, the problems of radiation source maintenance and radioactive operation dose in the traditional quality control scheme, and the statistical accuracy problem of background radiation quality control, etc.

[0006] (2) Technical Solutions

[0007] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0008] In a first aspect, an embodiment of the present invention provides a method for real-time calibration of a PET system based on real-time clinical scan data. The method includes: obtaining real-time clinical scan data; wherein the real-time clinical scan data is data during the acquisition of a PET image of a patient, and the real-time clinical scan data includes position information, energy information, and time information; performing statistical analysis on the energy information and / or time information of each PET detector of the PET system based on the position information to obtain real-time characteristic data of each crystal interval in a set crystal interval on each PET detector; wherein each crystal interval includes at least one crystal; calculating real-time calibration parameters for each crystal interval based on the real-time characteristic data of each crystal interval; and performing real-time calibration on the PET system using the real-time calibration parameters to ensure that the PET system is in an ideal working state.

[0009] In a possible embodiment, the real-time characteristic data includes real-time energy characteristic data, and the real-time calibration parameters include real-time gain calibration parameters corresponding to the real-time energy characteristic data;

[0010] Wherein, before obtaining the real-time clinical scan data, the method further includes: when it is confirmed that the PET system is in an ideal working state, obtaining standard energy characteristic data of each crystal interval in the PET system; the standard energy characteristic data includes a standard energy spectrum peak position and a standard signal mean value;

[0011] And, performing statistical analysis on the energy information and / or time information of each PET detector of the PET system based on the position information to obtain real-time characteristic data of each crystal interval in a set crystal interval on each PET detector, including: performing statistical analysis on the energy information of each PET detector based on the position information to obtain real-time energy characteristic data of each crystal interval; wherein the crystal interval is determined based on a gain adjustment channel corresponding to each detector, and the real-time energy characteristic data includes a real-time energy spectrum peak value or a real-time signal mean value, and the real-time signal mean value is the mean value of the magnitudes of the electrical signals generated after all crystals in the crystal interval detect gamma rays;

[0012] And, calculating real-time calibration parameters for each crystal interval based on the real-time characteristic data of each crystal interval, including: calculating real-time gain calibration parameters for each crystal interval using the real-time energy spectrum peak value and the standard energy spectrum peak position, or calculating real-time gain calibration parameters for each crystal interval using the real-time signal mean value and the standard signal mean value.

[0013] In a possible embodiment, the real-time gain calibration parameters are calculated by the following formula:

[0014] G cor =G cur *P ref / P cur ;

[0015] Among them, G cor is the real-time gain correction parameter of the current crystal interval; G cur is the actual gain of the current crystal interval; P ref is the standard energy spectrum peak position of the current crystal interval under the ideal working state; P cur is the real-time energy spectrum peak value corresponding to the current crystal interval.

[0016] In a possible embodiment, the real-time gain correction parameter is calculated by the following formula:

[0017] G cor = G cur * A ref / A cur ;

[0018] Among them, G cor is the real-time gain correction parameter of the current crystal interval; G cur is the actual gain of the current crystal interval; A ref is the standard signal mean value of the current crystal interval under the ideal working state; A cur is the real-time signal mean value of the current crystal interval.

[0019] In a possible embodiment, the real-time clinical scan data is obtained by performing signal electronics processing, digital conversion, and digital processing on the data collected by each PET detector in a plurality of PET detectors of the PET system;

[0020] Among them, using the real-time correction parameter to perform real-time correction on the PET system includes: determining whether the real-time gain correction parameter of the current crystal interval is within the gain adjustment range; if the real-time gain correction parameter is within the gain adjustment range, then using the real-time gain correction parameter to perform scaling processing on the electrical signals related to the current crystal interval in the signal electronics processing and / or digitization and digital processing; if the real-time gain correction parameter is outside the gain adjustment range, then generating an alarm signal carrying the identifier of the problem detector including the current crystal interval for manual intervention processing.

[0021] In a possible embodiment, the real-time feature data includes real-time time feature data, and the real-time correction parameter includes a real-time time correction delay corresponding to the real-time time feature data;

[0022] Among them, before obtaining the real-time clinical scan data, the method includes: when confirming that the PET system is in the ideal working state, obtaining the standard time feature data of each crystal interval in the PET system; the standard time feature data includes the standard time spectrum peak position and the standard coincidence time mean value;

[0023] And, based on the position information, perform statistical analysis on the energy information and / or time information of each PET detector in the PET system to obtain real-time characteristic data of each crystal interval in the set crystal interval of each PET detector, including: performing statistical analysis on the time information of each PET detector based on the position information to obtain real-time time characteristic data of each crystal interval; wherein, the crystal interval is determined based on the delay adjustment channel corresponding to each detector, and the real-time time characteristic data includes the real-time time spectrum peak value or the real-time coincidence time mean value, and the real-time coincidence time mean value is the mean value of the coincidence times of all events in the crystal interval;

[0024] And, based on the real-time characteristic data of each crystal interval, calculate the real-time correction parameter of each crystal interval, including: using the real-time time spectrum peak value and the standard time spectrum peak position to calculate the real-time time correction delay of each crystal interval, or using the real-time coincidence time mean value and the standard coincidence time mean value to calculate the real-time time correction delay of each crystal interval.

[0025] In a possible embodiment, calculate the real-time time correction delay through the following formula:

[0026] T cor =T cur +P Tref -P Tcur ;

[0027] Wherein, T cor is the real-time time correction delay of the current crystal interval; T cur is the actual delay of the current crystal interval; P Tref is the standard time spectrum peak position of the current crystal interval in the ideal working state; P Tcur is the real-time time spectrum peak value corresponding to the current crystal interval.

[0028] In a possible embodiment, calculate the real-time time correction delay through the following formula:

[0029] T cor =T cur +A Tref -A Tcur ;

[0030] Wherein, T cor is the real-time correction delay of the current crystal interval; T cur is the actual delay of the current crystal interval; A Tref is the standard coincidence time mean value of the current crystal interval in the ideal working state; A Tcur is the real-time coincidence time mean value of the current crystal interval.

[0031] In a possible embodiment, the real-time clinical scan data is obtained by performing signal electronics processing, digital conversion, and digital processing on the data collected by each PET detector among multiple PET detectors of a PET system;

[0032] Among them, performing real-time calibration on the PET system using real-time calibration parameters includes: determining whether the real-time calibration delay of the current crystal interval is within the delay adjustment range; if the real-time calibration delay is within the delay adjustment range, then using the real-time calibration delay to perform delay processing on the electrical signals related to the current crystal interval in signal electronics processing and / or digitization and digital processing; if the real-time calibration delay is outside the delay adjustment range, then generating an alarm signal carrying the identifier of the problematic detector including the current crystal interval for manual intervention processing.

[0033] In a possible embodiment, the real-time clinical scan data is completed by different hardware at different information stages, including: the data stream data in the acquisition logic gate array is used by the logic gate array to complete the feature data analysis and calculation of calibration parameters; the data packet data of the transmission node is used by the process of the embedded CPU to complete the feature data analysis and calculation of calibration parameters; the data temporarily stored in the memory and hard disk is used by any one of the acquisition or control computer workstations to complete the feature data analysis and calculation of calibration parameters.

[0034] In a second aspect, an embodiment of the present invention provides a storage medium as a carrier of a processing solution, on which a computer program or BITMAP of the connection definition of the logic gate array and the data stream operation logic is stored. When the BITMAP runs on the logic gate array or the computer program runs on the processor, the method described in the first aspect or any optional implementation manner of the first aspect is completed.

[0035] In a third aspect, an embodiment of the present invention provides an electronic device, which includes: a field programmable gate array (FPGA), an embedded processor, a computer terminal, a memory, a hard disk, a digital control amplifier, etc. While the electronic device is performing normal scan work, in parallel with the normal scan process of generating a patient image, the data is split and directed to an independent analysis process for analysis, such as an independent logic gate area of the FPGA, or a separate thread of a computer, and the independent FPGA interval or the separate computer thread completes the method described in the first aspect or any optional implementation manner of the first aspect.

[0036] (III) Beneficial effects

[0037] The beneficial effects of the present invention are:

[0038] The present invention obtains real-time PET clinical scan data including position information, energy information, and time information that conform to an event, and statistically analyzes the energy information and / or time information of each PET detector of the PET system based on the position information to obtain real-time characteristic data for each crystal interval in the set crystal intervals on each PET detector. Then, using the real-time characteristic data of each crystal interval, real-time correction parameters for each crystal interval are calculated, and the PET system is corrected in real-time using the real-time correction parameters to ensure that the PET system is in an ideal working state. Thus, compared with the existing technology, it can adjust the drift of the hardware in real-time and report the abnormal state of the system, avoiding the failure of the scanned image and the appearance of image artifacts caused by the system still working in a damaged and non-ideal state. It eliminates the step of specifically reserving time for the PET system to be debugged and corrected, thereby increasing the working time available for clinical scanning of the PET system, and avoiding the purchase cost of a dedicated radiation source and reducing the ionizing radiation dose brought by the operation of the radiation source.

[0039] In order to make the above objects, features, and advantages to be achieved by the embodiments of the present application more obvious and understandable, the following specifically lists preferred embodiments and, in conjunction with the accompanying drawings, makes a detailed description as follows. Brief Description of the Drawings

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the accompanying drawings required to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0041] Figure 1 Shows a schematic diagram of an energy window and signal drift in the prior art;

[0042] Figure 2 Shows a flowchart of a method for real-time correction of a PET system based on real-time clinical scan data provided by an embodiment of the present application;

[0043] Figure 3 Shows a specific flowchart of a method for simultaneously performing real-time correction during the acquisition of a PET image provided by an embodiment of the present application. Detailed Embodiments

[0044] In order to better explain the present invention for easy understanding, the following will make a detailed description of the present invention through specific embodiments in conjunction with the accompanying drawings.

[0045] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0046] PET is a clinical diagnostic imaging technology in the field of nuclear medicine. Its basic principle is to inject a tracer with positron-emitting radionuclides into the body, and then detect in vitro the energy, time and position information of a pair of 511keV gamma rays emitted in opposite directions after the positron annihilation. Finally, the location of the lesion is determined by statistically reconstructing the location of the annihilation event. This is a three-dimensional imaging non-destructive detection technology with the characteristics of high sensitivity, good accuracy and the ability to perform functional imaging.

[0047] Also, in the radiation detection system of PET, energy information is one of the key information. The energy information of PET affects the key indicators of the entire PET system, such as detection sensitivity, imaging uniformity, and imaging signal-to-noise ratio. In the field of radiation detection, the energy information of gamma rays cannot be obtained directly. Instead, the gamma rays are converted into electrical signals by the detector, and then the size of the detector output signal is obtained to characterize the energy information of the gamma rays. This means that instability in any link of the link, such as the conversion of gamma rays into electrical signals, as well as the amplification, transmission, and analysis of electrical signals, will affect the results of the energy information in the PET system, and thus affect the imaging effect of the PET system.

[0048] Also, during the use of radiation detectors for PET, due to the influence of factors such as temperature changes, voltage fluctuations, and device aging, each component in the detector will have a certain impact on the size of the final output signal. For example, the gain of the photomultiplier tube (PMT) will change with temperature changes. Also, changes in high voltage on the PMT will also affect the size of the gain; for another example, the temperature sensitivity of the silicon photomultiplier (SiPM) is more obvious, and its gain changes more with temperature. Also, changes in high voltage on the SiPM will also affect the size of the gain; for another example, in the scintillator detectors commonly used in PET systems, the light yield of the scintillator used is also affected by the temperature effect.

[0049] Since there is a certain amount of energy resolution in all radiation detectors, for example, the energy resolution of a detector using lutetium yttrium silicate (LYSO) scintillation crystal is about 12%, and the energy resolution of a detector using bismuth germanate (BGO) scintillator is about 18%. Since the γ-ray energy detected by PET is 511 keV, in practice, the ray signals within a certain energy window (such as 350 keV to 650 keV) are generally selected as effective rays. Because the ray signals are converted into electrical signals, the energy window is realized by screening electrical signals of a fixed size. This means that on the premise of a fixed energy window, if the signal size drifts, the actual energy window effect will change. For example, Figure 1 as shown, if the signal drifts and becomes smaller, the effective signals within the energy window will become fewer, resulting in a decrease in system sensitivity; if the signal drifts and becomes larger, not only may the effective signals within the energy window become fewer, but also some scattering events will enter the energy window, resulting in an increase in the system scattering fraction.

[0050] In order to reduce the influence of energy information changes on the PET system, traditional processing schemes are all based on the idea of quality control. For example, by ensuring the stability of the system operating temperature as much as possible, the influence brought by the temperature effects of the scintillator and the circuit can be reduced; for another example, by selecting electronic devices with good long-term stability, the instability influence brought by the fluctuations of the electronic devices can be reduced; for another example, based on the stability of the system, the debugging and calibration period of the system is determined to ensure the stability of the system operation within this period range. This is the operation quality control scheme for PET products.

[0051] However, the above operation quality control schemes are all carried out when the PET system is in a non-operating state, and the PET system needs to be left with a certain amount of time for debugging and calibration, and the purpose of real-time correcting the energy information of the system cannot be achieved.

[0052] In addition, in the prior art, a passive correction method for a positron emission tomography detector is also disclosed, which uses the energy signal of the background radioactive events of the LYSO scintillator as a reference for offline correcting the energy information of the system. However, this method also has the following problems:

[0053] First, the counting rate of the background event is relatively low, making it difficult to obtain a large amount of information in a short time, and the statistical fluctuation is large. Second, the 307 keV γ peak is also affected by the β decay peak, and the β decay energy peak is mixed into the γ energy peak, which will have a certain limitation on determining the energy accuracy of 307 keV. Third, the single-arm acquisition mode is used when collecting background events, while the system works in the coincidence acquisition mode in actual clinical practice. The calibration and the actual work cannot achieve the same data acquisition mode. Fourth, due to the large difference between the 307 keV used for calibration and the 511 keV in actual application, the system hardware states during calibration and operation are different, and the results also need to be extrapolated. When the energy linearity of the system is poor, large errors will be generated. Finally, this solution relies on the decay characteristics of the radioactive isotope of lutetium in the scintillator material. When the scintillator material is changed to a material without lutetium, this solution cannot be implemented.

[0054] To reduce the impact of energy information changes on the performance of the PET system, the current mainstream processing solutions are all based on the idea of quality control. Once a week or a day, data is collected through a special active quality control process to analyze the changes in the system and form calibration parameters. It usually requires users to purchase and maintain radiation sources, which is a significant expense. At the same time, users need to perform radioactive operations every day, and the radiation dose may cause potential harm to the operator. Moreover, this non-real-time calibration process cannot guarantee the calibration of changes in the hardware system during the scanning process. The passive quality control method developed using the background radiation of lutetium also cannot provide solutions in terms of real-time and accuracy. Periodic quality control also requires, including trying to ensure the stability of the system working temperature to reduce the impact of the temperature effect of the scintillator and the circuit; or selecting electronic devices with good long-term stability to reduce the instability impact caused by the fluctuation of electronic devices; or determining the debugging and calibration period of the system based on the system design stability to ensure the stability of the system within this period range.

[0055] Based on this, the embodiments of the present application provide a real-time correction scheme based on the clinical scan information of a PET system. By obtaining real-time PET clinical scan data including the position information, energy information, and time information of coincidence events, and by statistically analyzing the energy information and / or time information of each PET detector of the PET system based on the position information, and using the real-time characteristic data of each crystal interval to calculate the real-time correction parameters of each crystal interval, and using the real-time correction parameters to perform real-time correction on the PET system to ensure that the PET system is in an ideal working state. Thus, compared with the existing technologies, it can adjust the drift of the hardware in real time and report the abnormal state of the system, avoid the system damage and the situation that the scanning image fails and image artifacts appear when the system is still working in an unsatisfactory state, eliminate the step of specially reserving time for the PET system to be debugged and corrected, thereby increasing the working time of the PET system available for clinical scanning, and avoiding the purchase cost of dedicated radiation sources and reducing the ionizing radiation dose brought by the operation of radiation sources.

[0056] Please refer to Figure 2 , Figure 2 which shows a flowchart of a method for real-time correction of a PET system based on real-time clinical scan data provided by the embodiments of the present application. Specifically, as Figure 2 shown, the method can be executed by a specific device in the PET system, and the output data of the clinical scan of the PET system includes the position information, energy information, and time information of coincidence events, and the PET system includes a plurality of detectors, and each detector in the plurality of detectors includes a crystal array for detecting gamma rays, and the crystal array includes a plurality of crystals. The method includes:

[0057] Step S210, when it is confirmed that the PET system is in an ideal working state, obtain the standard energy characteristic data and / or standard time characteristic data of each crystal interval in the PET system. Among them, the standard energy characteristic data includes the standard energy spectrum peak position and the standard signal mean value; the standard time characteristic data includes the standard time spectrum peak position and the standard coincidence time mean value.

[0058] It should be understood that the standard energy characteristic data and / or standard time characteristic data can be the standard energy characteristic data, or the standard time characteristic data, or the standard energy characteristic data and the standard time characteristic data.

[0059] Step S220, obtain real-time clinical scan data. Among them, the real-time clinical scan data is the data during the acquisition process of the PET image of the patient, and the real-time clinical scan data includes the position information, energy information, and time information.

[0060] Step S230: Based on the position information, perform statistical analysis on the energy information and / or time information of each PET detector of the PET system to obtain the real-time characteristic data of each crystal interval in the set crystal intervals of each PET detector. Herein, each crystal interval includes at least one crystal.

[0061] Step S240: Calculate the real-time correction parameter of each crystal interval based on the real-time characteristic data of each crystal interval.

[0062] Step S250: Use the real-time correction parameter to perform real-time correction on the PET system to ensure that the PET system is in an ideal working state.

[0063] It should be noted here that Step S210 can ensure that the PET system is in an ideal working state during the initial debugging of the PET system or before leaving the factory. However, Step S250 determines that the PET system is in an ideal working state through the real-time correction method of this application during the actual operation of the PET system.

[0064] For ease of understanding Figure 2 , the following will be described through specific embodiments.

[0065] Please refer to Figure 3 , Figure 3 which shows the specific flowchart of a method for performing real-time correction during the acquisition of PET images provided by an embodiment of this application. As Figure 3 described, the method includes:

[0066] Step S310: Acquire the real-time clinical scan data of the target object. Herein, the real-time clinical scan data includes the position information, energy information, and time information of coincidence events.

[0067] It should be understood that the correction of the real-time clinical scan data is to perform system monitoring and compensatory adjustment during the imaging scan process to achieve real-time quality control. Moreover, it is different from independent active or passive quality control, which is independent of the scan, serves the scan, but is not simultaneous with the imaging scan.

[0068] It should also be understood that the target object can be a patient or a specially made positron-emitting phantom, and its significant feature is to perform quality control correction while imaging and scanning.

[0069] It should further be understood that the specific process of acquiring the real-time clinical scan data of the target object can be set according to actual needs, and the embodiments of this application are not limited thereto.

[0070] Optionally, when performing a PET scan on a target object, obtaining clinical scan data from the data stream is from the early stage of distributed analysis and acquisition. The quality control data information (corresponding to step S310, the following is similar and will not be elaborated one by one later) is directly collected from the digitization and digital processing process.

[0071] For example, when the PET system is a field programmable gate array (FPGA) and steps S310 to S330 are executed through the FPGA, when performing a PET scan on a target object, clinical scan data can be obtained in real time through the data stream in the FPGA, so as to enable real-time correction (corresponding to step S340).

[0072] Optionally, clinical scan data is obtained from the data packets of the transmission node, and the quality control data information comes from the patient clinical scan data acquisition process.

[0073] For example, the quality control data information collection step S310 obtains the data of the data packets (TCP / UDP) transmitted from the acquisition node in the embedded CPU, and the embedded computer analyzes the real-time transmitted data, executes steps S310 to S330, monitors the hardware status of the system and calculates the compensation amount for system drift, and completes real-time correction (corresponding to step S340).

[0074] Optionally, clinical scan data is read from the memory or hard disk, and the quality control data information comes from the caching process of the patient scan data acquisition process and the data information retrieval process.

[0075] For example, in a computer workstation where the PET system includes a CPU acquisition control terminal and steps S310 to S330 are executed through the CPU processor, the CPU processor reads the clinical scan data cached in the memory or hard disk. Among them, the clinical scan data cached in the memory or hard disk can be real-time scan data or data after a certain period of acquisition, as long as the data can represent the characteristics of the current hardware system, and form and complete compensation correction (corresponding to step S340).

[0076] For another example, when the PET system includes a computer that can be operated by a user and steps S310 to S330 are executed through the computer that can be operated by the user, the clinical scan data is read from the hard disk by the computer. That is, the quality control data information of step S310 comes from a certain computer node of data retrieval, image reconstruction and image analysis, and the analysis of steps S320 and S330 and the feedback compensation of step S340 are completed at this node. Among them, the clinical scan data stored in the hard disk can be real-time scan data or data after a certain period of acquisition.

[0077] It should also be understood that after the real-time feature information of the on-line analysis is converted into the hardware adjustment compensation amount, it is fed back to the information adjustable mechanism in real time (corresponding to step S340), including but not limited to, energy compensation to the numerical control gain amplifier, and time compensation to the numerical control delay parameter of the path time signal.

[0078] That is to say, any one of the data stream data in the logic gate array, the data packet data of the transmission node, and the clinical scan data temporarily stored in the memory or hard disk can be obtained, and the obtained data is used as the real-time clinical scan data.

[0079] It should be noted here that as Figure 3 shown, the real-time clinical scan data is obtained by performing signal electronics processing, digitization, and digital processing on the data collected by each PET detector in a plurality of PET detectors of the PET system. Among them, the signal electronics processing includes an analog processing process, amplifying and shaping the electrical signal, etc.; the digitization and digital processing include converting the pulse signal into a digital signal, and the magnitude and time of the digital signal. At the same time, logical analysis can also be performed on it. For example, meaningful information can be retained, and meaningless information can be deleted.

[0080] It should also be noted here that generally, energy information is not very useful in the image reconstruction process, and existing methods may not retain energy information, while the real-time clinical scan data in this application retains both the energy information and the time information required for image reconstruction.

[0081] To facilitate the understanding of step S310, the following will be described through specific embodiments.

[0082] Specifically, during the initial debugging of the PET system or before the PET system leaves the factory, when it is confirmed that the PET system is in an ideal working state, the amplitude of the electrical signal corresponding to the 511 keV gamma ray signal detected by each crystal in each detector among a plurality of detectors can be recorded. According to the action range of the electronically adjustable gain channel in the detector, one or more crystal intervals (also referred to as crystal combinations, etc.) are determined from the crystal array. Each crystal interval can include a single crystal or multiple crystals of N*M. Both N and M are positive integers.

[0083] In addition, the amplitude of the electrical signal in each crystal interval can be recorded separately, and thus an energy spectrum is formed and the standard energy spectrum peak position P ref of each crystal interval is recorded, or the standard signal mean value A ref of each crystal interval is statistically calculated. At the same time, the standard gain value G ref corresponding to each crystal interval in the ideal state can also be recorded.and can, according to the design of the PET system, confirm the gain adjustment range (G min , G max ) for determining the calibration method. For example, if the real-time gain calibration parameter of the crystal interval is outside the gain adjustment range, manual intervention is required; if the real-time gain calibration parameter of the crystal interval is within the gain adjustment range, the PET system can automatically make adjustments.

[0084] It should also be noted here that when subsequently using the PET system for PET scanning, there is no need to repeatedly perform the above initial debugging or pre-factory debugging, and it can be directly used.

[0085] It should be understood that the specific number of detectors, the specific number of crystal intervals, etc. can all be set according to actual needs, and the embodiments of the present application are not limited thereto.

[0086] It should also be understood that the specific method for determining one or more crystal intervals from the crystal array can be set according to actual needs, and the embodiments of the present application are not limited thereto.

[0087] For example, in the case of calculating the real-time gain calibration parameter of each crystal interval through the real-time energy spectrum peak or the real-time signal mean value, at least one gain adjustment channel for each detector can be determined, and one gain adjustment channel can correspond to one crystal interval, and the specific number of crystal intervals and the specific number of gain adjustment channels correspond one by one. Moreover, the crystal range affected by one gain adjustment channel is not necessarily the selected crystal interval, and the selected crystal interval can be the crystal interval with the most sensitive gain adjustment or even a single crystal interval.

[0088] For another example, in the case of calculating the real-time time correction delay of each crystal interval through the real-time time spectrum peak or the real-time coincidence time mean value, at least one delay adjustment channel for each detector can be determined, and one delay adjustment channel can correspond to one crystal interval, and the specific number of crystal intervals and the specific number of delay adjustment channels correspond one by one. Moreover, the crystal range affected by one delay adjustment channel is not necessarily the selected crystal interval, and the selected crystal interval can be the crystal interval with the most sensitive delay adjustment or even a single crystal interval.

[0089] It should also be understood that the specific range of gain adjustment or the specific range of delay adjustment can both be set according to actual needs, and the embodiments of the present application are not limited thereto.

[0090] It should also be understood that the standard signal mean value can also be referred to as the signal size mean value, etc.

[0091] Based on the above initial debugging, real-time clinical scan data can be obtained. Among them, the real-time clinical scan data may include crystal position information, energy information, and time information for each coincidence event, and the crystal position information and energy information can be traced back to obtain the two crystal positions corresponding to the occurrence of the event and the magnitudes of the energy signals corresponding to the two crystals. In addition, the corresponding position of each detector in the PET system can be given by the position information in the real-time clinical scan data, and the operating characteristic state of each detector can be given by the energy information and time information in the real-time clinical scan data.

[0092] Step S320: Statistically analyze the energy information and / or time information of each PET detector in the PET system based on the position information to obtain real-time characteristic data for each crystal interval in the set crystal intervals of each PET detector. Wherein, each crystal interval includes at least one crystal.

[0093] It should be understood that the energy information and / or time information can be energy information, time information, or both energy information and time information.

[0094] It should also be understood that the real-time characteristic data may include real-time energy characteristic data and / or real-time time characteristic data. Wherein, the real-time energy characteristic data and / or real-time time characteristic data can be real-time energy characteristic data, real-time time characteristic data, or both real-time energy characteristic data and real-time time characteristic data.

[0095] It should further be understood that the specific process of statistically analyzing the energy information and / or time information of each PET detector in the PET system based on the position information to obtain real-time characteristic data for each crystal interval in the set crystal intervals of each PET detector can be set according to actual requirements, and the embodiments of the present application are not limited thereto.

[0096] Optionally, when the real-time characteristic data includes real-time energy characteristic data and the real-time characteristic data includes real-time gain correction parameters corresponding to the real-time energy characteristic data, statistically analyzing the energy information of each PET detector in the PET system based on the position information to obtain real-time characteristic data for each crystal interval in the set crystal intervals of each PET detector includes: statistically analyzing the energy information of each PET detector based on the position information to obtain real-time energy characteristic data for each crystal interval; wherein, the crystal interval is determined based on the gain adjustment channel corresponding to each detector, and the real-time energy characteristic data includes a real-time energy spectrum peak or a real-time signal mean value, and the real-time signal mean value is the mean value of the magnitudes of the electrical signals generated after all crystals in the crystal interval detect gamma rays.

[0097] Optionally, when the real-time feature data includes real-time time feature data and the real-time correction parameter includes a real-time time correction delay corresponding to the real-time time feature data, perform statistical analysis on the time information of each PET detector of the PET system based on the position information to obtain the real-time feature data of each crystal interval in the set crystal interval of each PET detector, including: performing statistical analysis on the time information of each PET detector based on the position information to obtain the real-time time feature data of each crystal interval; wherein, the crystal interval is determined based on the delay adjustment channel corresponding to each detector, and the real-time time feature data includes the real-time time spectrum peak value or the real-time coincidence time mean value, and the real-time coincidence time mean value is the mean value of the coincidence times of all events in the crystal interval.

[0098] Step S330, calculate the real-time correction parameter of each crystal interval based on the real-time feature data of each crystal interval.

[0099] It should be understood that the specific process of calculating the real-time correction parameter of each crystal interval based on the real-time feature data of each crystal interval can be set according to requirements, and the embodiments of the present application are not limited thereto.

[0100] Optionally, when the real-time correction parameter includes a real-time gain correction parameter corresponding to the real-time energy feature data, use the real-time energy spectrum peak value and the standard energy spectrum peak position to calculate the real-time gain correction parameter of each crystal interval.

[0101] For example, the real-time gain correction parameter can be calculated through the following formula:

[0102] G cor =G cur *P ref / P cur ;

[0103] Wherein, G cor is the real-time gain correction parameter of the current crystal interval; G cur is the actual gain of the current crystal interval; P ref is the standard energy spectrum peak position of the current crystal interval under the ideal working state; P cur is the real-time energy spectrum peak value corresponding to the current crystal interval.

[0104] Optionally, when the real-time correction parameter includes a real-time gain correction parameter corresponding to the real-time energy feature data, use the real-time signal mean value and the standard signal mean value to calculate the real-time gain correction parameter of each crystal interval.

[0105] For example, the real-time gain correction parameter can be calculated through the following formula:

[0106] G cor =G cur*A ref / A cur ;

[0107] wherein, G cor is the real-time gain correction parameter of the current crystal interval; G cur is the actual gain of the current crystal interval; A ref is the standard signal mean value of the current crystal interval under the ideal working state; A cur is the real-time signal mean value of the current crystal interval.

[0108] Optionally, when the real-time correction parameter includes the real-time time correction delay corresponding to the real-time time characteristic data, the real-time time correction delay of each crystal interval is calculated by using the real-time time spectrum peak value and the standard time spectrum peak position.

[0109] For example, the real-time time correction delay can be calculated by the following formula:

[0110] T cor = T cur + P Tref - P Tcur ;

[0111] wherein, T cor is the real-time time correction delay of the current crystal interval; T cur is the actual delay of the current crystal interval; P Tref is the standard time spectrum peak position of the current crystal interval under the ideal working state; P Tcur is the real-time time spectrum peak value corresponding to the current crystal interval.

[0112] Optionally, when the real-time correction parameter includes the real-time time correction delay corresponding to the real-time time characteristic data, the real-time time correction delay of each crystal interval is calculated by using the real-time coincidence time mean value and the standard coincidence time mean value.

[0113] For example, the real-time time correction delay can be calculated by the following formula:

[0114] T cor = T cur + A Tref - A Tcur ;

[0115] wherein, T cor is the real-time correction delay of the current crystal interval; T cur is the actual delay of the current crystal interval; A Tref is the standard coincidence time mean value of the current crystal interval under the ideal working state; A Tcur is the real-time coincidence time mean value of the current crystal interval.

[0116] Step S340: Perform real-time calibration on the PET system using real-time calibration parameters to ensure that the PET system is in an ideal working state.

[0117] It should be understood that the specific process of performing real-time calibration on the PET system using real-time calibration parameters can be set according to actual needs, and the embodiments of the present application are not limited thereto.

[0118] Optionally, when the real-time calibration parameters include real-time gain calibration parameters corresponding to real-time energy characteristic data, determine whether the real-time gain calibration parameter of the current crystal interval is within the gain adjustment range. If the real-time gain calibration parameter is within the gain adjustment range, use the real-time gain calibration parameter to scale the electrical signals related to the current crystal interval in signal electronics processing and / or digitization and digital processing; if the real-time gain calibration parameter is outside the gain adjustment range, it can be determined that the detector or processing electronics hardware corresponding to the real-time calibration parameter of the PET system may be faulty, and thus an alarm signal carrying the identifier of the problem detector including the current crystal interval can be generated for manual intervention, so as to be able to perform fault troubleshooting on the detector and the corresponding electronics hardware corresponding to the real-time calibration parameter of the PET system. Among them, the specific range of the gain adjustment range can be set according to actual needs.

[0119] It should be noted here that after the crystal detects gamma rays, it generates an electrical signal, and the electrical signal needs to go through electrical signal processing to generate a PET image. Among them, the electrical signal processing process can include the amplification of the electrical signal. Thus, when it is determined that the real-time calibration parameter of the current crystal interval is within the gain adjustment range, the embodiments of the present application can scale the electrical signals corresponding to the current crystal interval (i.e., the electrical signals related to signal electronics processing and / or digitization and digital processing, etc.), so as to achieve signal compensation and make the finally generated PET image accurate.

[0120] Optionally, when the real-time calibration parameters include real-time time calibration delays corresponding to real-time time characteristic data, determine whether the real-time calibration delay of the current crystal interval is within the delay adjustment range. If the real-time calibration delay is within the delay adjustment range, use the real-time calibration delay to delay the electrical signals related to the current crystal interval in signal electronics processing and / or digitization and digital processing; if the real-time calibration delay is outside the delay adjustment range, it can be determined that the detector or processing electronics hardware corresponding to the real-time calibration parameter of the PET system may be faulty, and thus an alarm signal carrying the identifier of the problem detector including the current crystal interval can be generated for manual intervention, so as to be able to perform fault troubleshooting on the detector and the corresponding electronics hardware corresponding to the real-time calibration parameter of the PET system. Among them, the specific range of the delay adjustment range can also be set according to actual needs.

[0121] In addition, during the process of calibrating the PET system using the real-time calibration parameters of the current crystal interval, the change in signal amplitude can be analyzed within the selected time period, and new real-time calibration parameters can be uploaded to the PET system parameters at a set moment (or at any time) to complete the calibration operation to compensate for the change. The shorter the analysis time, the better the real-time performance. The analysis time period can be selected between milliseconds and several hours.

[0122] Furthermore, this quality control analysis of patient data does not affect the patient's scanning process, but only uses the collected information in parallel. On the one hand, the information is collected, analyzed, and image reconstructed according to the normal PET scanning process. On the other hand, the information is diverted and the quality control analysis of this technology is completed for quality control.

[0123] Moreover, the information of PET adopts a distributed acquisition method, and this technology can be applied to all links of the acquisition link:

[0124] The calibration process can be built into the front-end hardware circuit of the PET system. The mechanism for recording and analyzing regional events can be during the data acquisition process of the PET system, in the field-programmable gate array (FPGA) in the hardware, and a block of logic resources is opened for each crystal interval event to realize the recording and analysis of information. The size of the number of events n can be determined according to the hardware resources. For example, a suitable value can be selected between dozens and several megabytes. Also, the average energy of the over-energy window can be statistically analyzed, which uses less storage and computing resources. Also, the energy spectrum can be accumulated and the peak position can be analyzed, which occupies more storage and computing resources;

[0125] In the information data transmission link, when the information is transmitted to the computer memory, when the computer completes the conventional object scanning task, the computer thread analyzes the transmitted data in real time, analyzes it according to the designed time period, forms updated calibration data, and then completes the transmission of the calibration information back to the information compensation link in real time or at a selected time point. Due to the use of the computer for real-time analysis, the calibration parameters are no longer limited to energy information, but can also include other working parameters;

[0126] In the information storage link, the patient's data is stored on the hard disk while being scanned and analyzed in real time. The patient's data is generally stored in a single independent file in the form of a single bed. Analyzing by a single bed, or a single patient (multiple beds), or multiple patient data, the analysis system drifts and changes during this time period, forms calibration parameters, and transmits them back to set the system parameters. This method is relatively reliable, and the update of the calibration parameters can be selected to be completed during the scanning interval of the scanning process. Similarly, the calibration parameters are no longer limited to energy information, but can also include other working parameters.

[0127] In addition, continue to refer to Figure 3, after obtaining real-time clinical scan data, in addition to the above steps, after obtaining real-time clinical scan data, the steps of data retrieval to form a sine graph, image reconstruction, and image medical record analysis can also be executed in parallel in sequence to complete a normal image scan.

[0128] Therefore, by means of the above technical solution, the embodiments of the present application utilize the energy data and / or time information during the object's PET scan to perform real-time analysis and correction work, thereby improving the timeliness, accuracy, and generality of energy correction.

[0129] To facilitate the understanding of the embodiments of the present application, the following will be described through specific embodiments.

[0130] Specifically, when each detector in the PET system includes 14*14 crystals and each detector has four gain adjustment channels, each detector can thus be divided into four crystal intervals of 7*7.

[0131] It should be noted here that a crystal interval can be composed of 7*7 crystals, or can be composed of at least one crystal selected from 7*7 crystals.

[0132] And, when the energy state of the detector is initially adjusted and it is confirmed that the detector is working in an ideal state, data is collected, and the standard energy spectrum peak positions of the four crystal intervals in a certain detector are respectively 301.5, 300.2, 298.6, and 300.5. At this time, the corresponding standard gains of the four crystal intervals are respectively 5.46, 5.38, 5.51, and 5.25. According to the system design, when the signal change exceeds ±15%, it is considered that the system has changed significantly and requires manual intervention.

[0133] And, when the PET system is working, after scanning a certain patient, the energy information in the patient data during this period is statistically analyzed, and the real-time energy spectrum peak values of the four crystal intervals in the detector are respectively 305.2, 303.5, 305.8, and 306.7, and the real-time four-channel gain values are respectively 5.52, 5.46, 5.61, and 5.32.

[0134] And according to the above formula, the corrected four-channel real-time gain correction parameters are respectively 5.45, 5.40, 5.48, and 5.21. The calculated real-time gain correction parameters are uploaded to the PET system to ensure that the system energy information works in an ideal state.

[0135] And, if it is confirmed that the difference between the four-channel real-time gain correction parameters and the standard gain values does not exceed ±15%, no manual intervention is required, thereby the energy information correction of the detector can be completed. And, the remaining detectors in the PET system are also corrected for energy information according to this method.

[0136] It should be understood that the above method for real-time calibration of the PET system based on real-time clinical scan data is merely exemplary, and those skilled in the art can make various deformations according to the above method, and the solutions after such deformations also fall within the protection scope of this application.

[0137] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can be implemented in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can be implemented in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0138] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram can be implemented by computer program instructions, and the combination of processes and / or blocks in the flowchart and / or block diagram can also be implemented by computer program instructions.

[0139] It should be noted that in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of components or steps not listed in the claim. The word "a" or "an" placed before a component does not exclude the presence of a plurality of such components. The present invention can be implemented by means of hardware including several different components and by means of a suitably programmed computer. In a claim listing several devices, several of these devices can be embodied by the same hardware. The use of the terms first, second, third, etc. is only for the convenience of expression and does not denote any order. These terms can be understood as part of the component name.

[0140] In addition, it should be noted that in the description of this specification, the description of terms such as "one embodiment", "some embodiments", "embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0141] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications after learning the basic creative concept. Therefore, the claims should be construed to cover the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0142] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention should also include these modifications and variations.

Claims

1. A method for real-time correction of a PET system based on real-time clinical scan data, characterized in that Comprising: Obtaining the real-time clinical scan data; wherein, the real-time clinical scan data is data during the acquisition process of a patient's PET image, and the real-time clinical scan data includes position information, energy information, and time information of coincidence events; Based on the position information, statistically analyzing the energy information and / or time information of each PET detector of the PET system to obtain real-time characteristic data of each crystal interval in the set crystal intervals on each PET detector; wherein, each crystal interval includes at least one crystal; Based on the real-time characteristic data of each crystal interval, calculating real-time correction parameters for each crystal interval; the real-time characteristic data includes real-time energy characteristic data or real-time time characteristic data, and the real-time correction parameters include real-time gain correction parameters corresponding to the real-time energy characteristic data or real-time time correction delays corresponding to the real-time time characteristic data; Using the real-time correction parameters to perform real-time correction on the PET system to ensure that the PET system is in an ideal working state.

2. The method according to claim 1, wherein The real-time characteristic data includes the real-time energy characteristic data, and the real-time correction parameters include real-time gain correction parameters corresponding to the real-time energy characteristic data; Wherein, before obtaining the real-time clinical scan data, the method further includes: When it is confirmed that the PET system is in an ideal working state, obtaining standard energy characteristic data of each crystal interval in the PET system; the standard energy characteristic data includes standard energy spectrum peak positions and standard signal means; And, the statistically analyzing the energy information and / or time information of each PET detector of the PET system based on the position information to obtain real-time characteristic data of each crystal interval in the set crystal intervals on each PET detector includes: Statistically analyzing the energy information of each PET detector based on the position information to obtain real-time energy characteristic data of each crystal interval; wherein, the crystal interval is determined based on the gain adjustment channel corresponding to each detector, and the real-time energy characteristic data includes real-time energy spectrum peak values or real-time signal means, and the real-time signal mean is the mean of the magnitudes of the electrical signals generated after all crystals in the crystal interval detect gamma rays; And, the calculating the real-time correction parameters for each crystal interval based on the real-time characteristic data of each crystal interval includes: Calculating the real-time gain correction parameter for each crystal interval by using the real-time energy spectrum peak value and the standard energy spectrum peak position, or calculating the real-time gain correction parameter for each crystal interval by using the real-time signal mean and the standard signal mean.

3. The method according to claim 2, wherein Calculating the real-time gain correction parameter through the following formula: ； Among them, is the real-time gain correction parameter for the current crystal interval; is the actual gain of the current crystal interval; is the standard energy spectrum peak position of the current crystal interval under the ideal working state; is the real-time energy spectrum peak value corresponding to the current crystal interval.

4. The method according to claim 2, wherein Calculating the real-time gain correction parameter through the following formula: ； Among them, is the real-time gain correction parameter of the current crystal interval; is the actual gain of the current crystal interval; is the standard signal mean value of the current crystal interval under the ideal working state; is the real-time signal mean value of the current crystal interval.

5. The method according to claim 2, wherein The real-time clinical scan data is obtained by performing signal electronics processing, digital conversion, and digital processing on the data collected by each PET detector in multiple PET detectors of the PET system; Among them, the real-time calibration of the PET system using the real-time calibration parameters includes: Determining whether the real-time gain calibration parameter of the current crystal interval is within the gain adjustment range; If the real-time gain calibration parameter is within the gain adjustment range, using the real-time gain calibration parameter to scale the electrical signals related to the current crystal interval in the signal electronics processing and / or the digital conversion and digital processing; If the real-time gain calibration parameter is outside the gain adjustment range, generating an alarm signal carrying the identifier of the problem detector including the current crystal interval for manual intervention processing.

6. The method according to claim 1, characterized in that, The real-time characteristic data includes the real-time time characteristic data, and the real-time calibration parameter includes the real-time time calibration delay corresponding to the real-time time characteristic data; Among them, before obtaining the real-time clinical scan data, the method further includes: When confirming that the PET system is in an ideal working state, obtaining the standard time characteristic data of each crystal interval in the PET system; the standard time characteristic data includes the standard time spectrum peak position and the standard coincidence time mean value; And, the statistical analysis of the energy information and / or time information of each PET detector of the PET system based on the position information to obtain the real-time characteristic data of each crystal interval in the set crystal interval of each PET detector, including: Statistically analyzing the time information of each PET detector based on the position information to obtain the real-time time characteristic data of each crystal interval; wherein, the crystal interval is determined based on the delay adjustment channel corresponding to each detector, and the real-time time characteristic data includes the real-time time spectrum peak value or the real-time coincidence time mean value, and the real-time coincidence time mean value is the mean value of the coincidence times of all events in the crystal interval; And, calculating the real-time calibration parameter of each crystal interval based on the real-time characteristic data of each crystal interval, including: Calculating the real-time time calibration delay of each crystal interval using the real-time time spectrum peak value and the standard time spectrum peak position, or calculating the real-time time calibration delay of each crystal interval using the real-time coincidence time mean value and the standard coincidence time mean value.

7. The method according to claim 6, wherein Calculating the real-time time calibration delay through the following formula: ； Among them, is the real-time time correction delay of the current crystal interval; is the actual delay of the current crystal interval; is the standard time spectrum peak position of the current crystal interval under the ideal working state; is the real-time time spectrum peak value corresponding to the current crystal interval.

8. The method according to claim 6, characterized in that Calculating the real-time time calibration delay through the following formula: ； Wherein, is the real-time correction delay of the current crystal interval; is the actual delay of the current crystal interval; is the standard coincidence time mean value of the current crystal interval under the ideal working state; is the real-time coincidence time mean value of the current crystal interval.

9. The method according to claim 6, wherein The real-time clinical scan data is obtained after signal electronics processing and digital conversion and digital processing of the data collected by each PET detector in multiple PET detectors of the PET system; Among them, the real-time calibration of the PET system using the real-time calibration parameters includes: Determining whether the real-time calibration delay of the current crystal interval is within the delay adjustment range; If the real-time calibration delay is within the delay adjustment range, using the real-time calibration delay to perform delay processing on the electrical signals related to the current crystal interval in the signal electronics processing and / or the digital conversion and digital processing; If the real-time correction delay is outside the delay adjustment range, an alarm signal carrying the identifier of the problem detector including the current crystal interval is generated for manual intervention.

10. The method according to claim 1, characterized in that, The real-time clinical scan data is completed by different hardware at different information stages, including: the data flow data in the acquisition logic gate array is used to complete the feature data analysis and the calculation of calibration parameters by the logic gate array; the data packet data of the transmission node is used to complete the feature data analysis and the calculation of calibration parameters by the process of the embedded CPU; the data temporarily stored in the memory and the hard disk is used to complete the feature data analysis and the calculation of calibration parameters by any one of the acquisition or control computer workstations.

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