Energy correction method and device, electronic equipment and storage medium

Abstract

The invention relates to an energy correction method and device, electronic equipment and a storage medium. An event obtained by scanning a target radioactive source is obtained, correction is performed based on scattering characteristics of the event and preset first correction energy to obtain a corresponding gain correction coefficient, fitting is performed based on the first correction energy, preset background energy and a corresponding energy measurement value to obtain a corresponding first correction coefficient, and the target radioactive source is obtained. And performing fitting based on the first correction energy, the background energy, preset second correction energy and a corresponding energy measurement value to obtain a corresponding second correction coefficient, and further performing energy correction on the to-be-processed event by adopting the gain correction coefficient and the first correction coefficient or adopting the gain correction coefficient and the second correction coefficient according to the correction instruction. The second correction coefficient is used for high-energy correction, so that high-energy correction can be realized based on the method, and the calculation precision of a high-energy part is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of data processing, and in particular, to an energy correction method and device, electronic equipment, computer readable storage medium, and computer program product. BACKGROUND

[0002] Positron Emission Tomography (PET) is a medical imaging technology that reflects the metabolic activity of human tissues by detecting the annihilation signal of a radioactive tracer.

[0003] The working principle of PET is to label a radioactive nuclide emitting a positron to a compound that can participate in the blood flow or metabolic process of living tissues, and inject the compound labeled with the radioactive nuclide into the organism. The positron emitted by the radioactive nuclide decays in the organism and combines with the negative electron in the organism, thereby causing an annihilation event of an electron pair, generating two gamma photons with equal energy and opposite directions. Therefore, the two gamma photons can be detected by a detector probe. If two gamma photons are detected by two scintillation crystals in the detector on the line of response (LOR) within a specified coincidence time window (for example, 0-15 nanoseconds) and an energy window (400-600 keV), the event of detecting the two gamma photons can be referred to as a coincidence event. Subsequently, the PET image of the subject can be reconstructed according to the information of the coincidence event.

[0004] Ideally, the response of each detector to a 511 keV photon is completely consistent. When a 511 keV photon enters the crystal, it deposits the full energy, and the detector outputs a voltage information corresponding to 511 keV. However, due to the inherent physical and engineering limitations of the PET system, even the same batch of scintillation crystals will have slight differences in light yield, attenuation length, and energy resolution. In addition, the photoelectric conversion efficiency and gain of each detection unit cannot be exactly the same, and the parameters of the electronic components will also have drift and differences, etc. Therefore, energy correction is needed to correct the energy peak of each detection unit of the system to 511 keV.

[0005] Traditional energy correction techniques generally correct based on the background energy of the detector and 511 keV, which may not be accurate in high-energy calculations, especially when high-energy windows are used to screen special photons, which may cause energy spectrum deviation, resulting in inaccurate screening of the required photons. SUMMARY

[0006] The present application provides an energy correction method, device, electronic equipment, computer readable storage medium and computer program product to at least solve the problem of inaccurate calculation of high-energy parts in the related art. The technical solutions of the present application are as follows:

[0007] According to a first aspect of an embodiment of the present application, an energy correction method is provided, the method comprising:

[0008] Obtaining events obtained by scanning a target radioactive source;

[0009] Based on the scattering characteristics of the events and a preset first correction energy, performing correction to obtain corresponding gain correction coefficients;

[0010] Based on the first correction energy, a preset background energy and corresponding energy measurement values, fitting is performed to obtain corresponding first correction coefficients;

[0011] Based on the first correction energy, the background energy and a preset second correction energy and corresponding energy measurement values, fitting is performed to obtain corresponding second correction coefficients; the second correction energy is greater than the first correction energy;

[0012] According to a correction instruction, the gain correction coefficients and the first correction coefficients are used, or the gain correction coefficients and the second correction coefficients are used, to perform energy correction on the events to be processed; the correction instruction includes an indication of whether to perform high-energy correction.

[0013] In one of the embodiments, the gain correction coefficients include first gain coefficients; based on the scattering characteristics of the events and a preset first correction energy, performing correction to obtain corresponding gain correction coefficients, comprises: determining non-scattering events based on the scattering characteristics of the events; determining first energy distribution spectra of each channel in each detector according to the first energy range of the non-scattering events; determining first energy peak values corresponding to each channel respectively according to the first energy distribution spectra of each channel; based on the preset first correction energy, correcting the first energy peak values corresponding to each channel respectively to determine first gain coefficients corresponding to each channel respectively.

[0014] In one of the embodiments, the gain correction coefficient further comprises a second gain coefficient; and the correction based on the scattering feature of the event and the preset first correction energy to obtain the corresponding gain correction coefficient comprises: determining a primary scattering event based on the scattering feature of the event; performing energy correction on the primary scattering event according to the first gain coefficient corresponding to each channel to obtain the energy of the primary scattering event after correction; determining a second energy distribution spectrum of each channel of each detector based on the energy of the primary scattering event after correction and a preset second energy range; determining a second energy peak value corresponding to each channel based on the second energy distribution spectrum of each channel; and determining the second gain coefficient corresponding to each channel based on the correction of the second energy peak value corresponding to each channel based on the preset first correction energy.

[0015] In one of the embodiments, the energy correction on the primary scattering event according to the first gain coefficient corresponding to each channel to obtain the energy of the primary scattering event after correction comprises: determining a first channel corresponding to a first energy and a second channel corresponding to a second energy in the primary scattering event; obtaining a first product of the first gain coefficient corresponding to the first channel and the first energy; obtaining a second product of the first gain coefficient corresponding to the second channel and the second energy; and obtaining a sum of the first product and the second product, and determining the sum as the energy of the primary scattering event after correction.

[0016] In one of the embodiments, the gain correction coefficient further comprises a third gain coefficient; and the correction based on the scattering feature of the event and the preset first correction energy to obtain the corresponding gain correction coefficient comprises: determining a multiple scattering event based on the scattering feature of the event; performing energy correction on the multiple scattering event according to the first gain coefficient corresponding to each channel to obtain the energy of the multiple scattering event after correction; determining a third energy distribution spectrum of each detector based on the energy of the multiple scattering event after correction and a preset third energy range; determining a third energy peak value corresponding to each detector based on the third energy distribution spectrum of each detector; and determining the third gain coefficient corresponding to each detector based on the correction of the third energy peak value corresponding to each detector based on the preset first correction energy.

[0017] In one of the embodiments, the energy correction of the multiple scattering events according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the multiple scattering events comprises: determining the first channel corresponding to the first energy, the second channel corresponding to the second energy, and the third channel corresponding to the third energy in the multiple scattering events; obtaining the first product of the first gain coefficient corresponding to the first channel and the first energy; obtaining the second product of the first gain coefficient corresponding to the second channel and the second energy; obtaining the third product of the first gain coefficient corresponding to the third channel and the third energy; obtaining the sum of the first product, the second product and the third product, and determining the sum as the corrected energy of the multiple scattering events.

[0018] In one of the embodiments, the fitting based on the first corrected energy, the preset background energy and the corresponding energy measurement value to obtain the corresponding first correction coefficient comprises: determining the first energy measurement value corresponding to the first corrected energy, and determining the second energy measurement value corresponding to the background energy; fitting the preset first fitting function based on the first corrected energy, the first energy measurement value, the background energy and the second energy measurement value to obtain the first nonlinear coefficient; performing the axial consistency correction based on the scattering feature of the event and the preset first corrected energy to obtain the corresponding first uniformity correction coefficient; and determining the corresponding first correction coefficient according to the first nonlinear coefficient and the first uniformity correction coefficient.

[0019] In one of the embodiments, the fitting based on the first correction energy, the background energy, and a preset second correction energy and corresponding energy measurement values to obtain corresponding second correction coefficients comprises: determining a first energy measurement value corresponding to the first correction energy, determining a second energy measurement value corresponding to the background energy, and determining a no-scattering energy peak value corresponding to the second correction energy; fitting a preset first fitting function based on the first correction energy, the first energy measurement value, the background energy, the second energy measurement value, the second correction energy, and the no-scattering energy peak value to obtain corresponding second nonlinear coefficients; determining a first-order scattering energy peak value corresponding to the second correction energy, fitting a preset second fitting function based on the second correction energy and the first-order scattering energy peak value to obtain a first-order scattering nonlinear correction coefficient; determining a multiple scattering energy peak value corresponding to the second correction energy, fitting a preset third fitting function based on the second correction energy and the multiple scattering energy peak value to obtain a multiple scattering nonlinear correction coefficient; performing axial consistency correction based on the scattering feature of the event and the preset second correction energy to obtain corresponding second uniformity correction coefficients; and determining the corresponding second correction coefficients according to the second nonlinear coefficients, the first-order scattering nonlinear correction coefficient, the multiple scattering nonlinear correction coefficient, and the second uniformity correction coefficients.

[0020] In one of the embodiments, the determination of the no-scattering energy peak value corresponding to the second correction energy comprises: determining no-scattering events based on the scattering feature of the event; performing energy correction on the no-scattering events according to the first gain coefficients respectively corresponding to each channel to obtain corrected energies of the no-scattering events; determining fourth energy distribution spectrums of each channel in each detector based on the corrected energies of the no-scattering events and a preset fourth energy range; the second correction energy is located in the fourth energy range; determining fourth energy peak values respectively corresponding to each channel according to the fourth energy distribution spectrums of each channel; and determining the fourth energy peak values respectively corresponding to each channel as the no-scattering energy peak values corresponding to the second correction energy.

[0021] In one of the embodiments, the determining the primary scattering energy peak corresponding to the second correction energy comprises: determining a primary scattering event based on the scattering feature of the event; performing energy correction on the primary scattering event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the primary scattering event; determining a fifth energy distribution spectrum for each channel of each detector based on the corrected energy of the primary scattering event and a preset fifth energy range; the second correction energy is within the fifth energy range; determining a fifth energy peak corresponding to each channel based on the fifth energy distribution spectrum of each channel; and determining the fifth energy peak corresponding to each channel as the primary scattering energy peak corresponding to the second correction energy.

[0022] In one of the embodiments, the determining the multiple scattering energy peak corresponding to the second correction energy comprises: determining a multiple scattering event based on the scattering feature of the event; performing energy correction on the multiple scattering event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the multiple scattering event; determining a sixth energy distribution spectrum for each detector based on the corrected energy of the multiple scattering event and a preset sixth energy range; determining a sixth energy peak corresponding to each detector based on the sixth energy distribution spectrum of each detector; and determining the sixth energy peak corresponding to each detector as the multiple scattering energy peak corresponding to the second correction energy.

[0023] In one of the embodiments, the determining the first energy measurement value corresponding to the first correction energy comprises: determining a non-scattering event based on the scattering feature of the event; performing energy correction on the non-scattering event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the non-scattering event; determining a seventh energy distribution spectrum for each channel of each detector based on the corrected energy of the non-scattering event and a preset seventh energy range; the first correction energy is within the seventh energy range; determining a seventh energy peak corresponding to each channel based on the seventh energy distribution spectrum of each channel; and determining the seventh energy peak corresponding to each channel as the first energy measurement value corresponding to the first correction energy.

[0024] In one of the embodiments, the determining the second energy measurement value corresponding to the background energy comprises: obtaining a non-scattering empty sampling event based on a scattering feature of an empty sampling event; performing energy correction on the non-scattering empty sampling event according to the first gain coefficient corresponding to each channel to obtain the energy of the non-scattering empty sampling event after correction; determining an eighth energy distribution spectrum of each channel of the detector based on the energy of the non-scattering empty sampling event after correction and a preset eighth energy range; determining an eighth energy peak value in each channel according to the eighth energy distribution spectrum of each channel and the background energy; and taking the eighth energy peak value of each channel as the corresponding second energy measurement value.

[0025] In one of the embodiments, the axial consistency correction comprises: determining a scattering event between detectors based on a scattering feature of the event; determining a peak value energy corresponding to a target correction energy according to the scattering event between detectors; the target correction energy comprises the first correction energy or the second correction energy; and fitting a preset fourth fitting function based on the target correction energy and the corresponding peak value energy.

[0026] In one of the embodiments, the energy correction on the to-be-processed event according to the correction instruction by using the gain correction coefficient and the first correction coefficient or by using the gain correction coefficient and the second correction coefficient comprises: in a case where it is determined that the correction instruction does not include an indication of performing high-energy correction, performing energy correction on the to-be-processed event by using the gain correction coefficient and the first correction coefficient; and in a case where it is determined that the correction instruction includes an indication of performing high-energy correction, performing energy correction on the to-be-processed event by using the gain correction coefficient and the second correction coefficient.

[0027] In one of the embodiments, the target radioactive source is a radioactive source containing a radioactive isotope Na 22 .

[0028] According to a second aspect of the embodiments of the present application, an energy correction device is provided, comprising:

[0029] An event obtaining module is configured to perform obtaining an event scanned by a target radioactive source;

[0030] A gain determining module is configured to perform correction based on a scattering feature of the event and a preset first correction energy to obtain a corresponding gain correction coefficient;

[0031] A first fitting module is configured to perform fitting based on the first correction energy, a preset background energy and a corresponding energy measurement value to obtain a corresponding first correction coefficient;

[0032] The second fitting module is configured to perform fitting based on the first correction energy, the background energy, a preset second correction energy, and corresponding energy measurement values, to obtain a corresponding second correction coefficient; the second correction energy is greater than the first correction energy.

[0033] The correction module is configured to perform energy correction on a to-be-processed event according to a correction instruction, by using the gain correction coefficient and the first correction coefficient, or by using the gain correction coefficient and the second correction coefficient; the correction instruction includes an indication of whether to perform high-energy correction.

[0034] According to a third aspect of the embodiments of the present application, an electronic device is provided, including a memory and a processor, the memory stores a computer program, and the processor implements the steps of the method of the first aspect when executing the computer program.

[0035] According to a fourth aspect of the embodiments of the present application, a computer readable storage medium is provided, which stores a computer program, and the computer program is executed by a processor to implement the steps of the method of the first aspect. The following steps are implemented:

[0036] According to a fifth aspect of the embodiments of the present application, a computer program product is provided, including a computer program, and the computer program is executed by a processor to implement the steps of the method of the first aspect.

[0037] The technical solutions provided by the embodiments of the present application at least bring the following beneficial effects:

[0038] By obtaining events scanned by a target radioactive source, correction is performed based on the scattering characteristics of the events and a preset first correction energy to obtain a corresponding gain correction coefficient, fitting is performed based on the first correction energy and a preset background energy and corresponding energy measurement values to obtain a corresponding first correction coefficient, fitting is performed based on the first correction energy, the background energy and a preset second correction energy and corresponding energy measurement values to obtain a corresponding second correction coefficient, and then energy correction is performed on to-be-processed events according to a correction instruction, by using the gain correction coefficient and the first correction coefficient, or by using the gain correction coefficient and the second correction coefficient. Since the second correction coefficient is used for high-energy correction, the above method can realize high-energy correction, improve the calculation accuracy of the high-energy part, and adapt to different correction modes according to actual needs, thereby improving the flexibility of correction.

[0039] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0040] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application and, do not limit its scope.

[0041] Figure 1 is a flowchart of an energy correction method according to an exemplary embodiment.

[0042] Figure 2 is a flowchart of a gain correction coefficient determination step according to an exemplary embodiment.

[0043] Figure 3 is a first energy distribution spectrum diagram according to an exemplary embodiment.

[0044] Figure 4 is a flowchart of a gain correction coefficient determination step according to another exemplary embodiment.

[0045] Figure 5 is a second energy distribution spectrum diagram according to an exemplary embodiment.

[0046] Figure 6 is a flowchart of a gain correction coefficient determination step according to yet another exemplary embodiment.

[0047] Figure 7 is a third energy distribution spectrum diagram according to an exemplary embodiment.

[0048] Figure 8 is a flowchart of a first correction coefficient acquisition step according to an exemplary embodiment.

[0049] Figure 9 is an eighth energy distribution spectrum diagram according to an exemplary embodiment.

[0050] Figure 10 is an energy distribution spectrum diagram according to an exemplary embodiment.

[0051] Figure 11 is a flowchart of a second correction coefficient acquisition step according to an exemplary embodiment.

[0052] Figure 12 is a fourth energy distribution spectrum diagram according to an exemplary embodiment.

[0053] Figure 13 is a fifth energy distribution spectrum diagram according to an exemplary embodiment.

[0054] Figure 14 is a sixth energy distribution spectrum diagram according to an exemplary embodiment.

[0055] Figure 15A This is a schematic diagram of the data verification energy spectrum according to an exemplary embodiment.

[0056] Figure 15B This is a schematic diagram of the data verification energy spectrum according to an exemplary embodiment.

[0057] Figure 16 This is a block diagram illustrating an energy correction device according to an exemplary embodiment.

[0058] Figure 17 This is a block diagram illustrating an electronic device according to an exemplary embodiment. Detailed Implementation

[0059] To enable those skilled in the art to better understand the technical solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0060] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0061] It should also 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 display, data used for analysis, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0062] In one embodiment, such as Figure 1 As shown, an energy correction method is provided, which can be applied to PET equipment, and specifically includes the following steps:

[0063] In step S102, events obtained from scanning the target radiation source are acquired.

[0064] The target radioactive source can be a standard radioactive source containing at least one gamma-ray source of known energy. For example, the target radioactive source can be a source containing the radioactive isotope Na. 22 (Sodium-22) is a radioactive source. Because Na... 22The source is a radioactive source that generates positrons through decay, which in turn produce pairs of gamma photons with opposite directions and energies of 511 keV, while also releasing a gamma photon of 1274 keV. Therefore, it perfectly simulates the core physical events in PET imaging, playing an irreplaceable role in the quality assurance, performance calibration, and routine maintenance of PET systems, and is the cornerstone of ensuring the accuracy and quantitative precision of PET images.

[0065] In this embodiment, by using Na 22 The source is scanned for a certain period of time to obtain raw data, which is then parsed to obtain all the parsed events. These events include those in which no scattering occurred within the crystal (i.e., no-scattering events) and those in which scattering occurred within the crystal (i.e., scattering events).

[0066] In step S104, correction is performed based on the scattering characteristics of the event and the preset first correction energy to obtain the corresponding gain correction coefficient.

[0067] Scattering characteristics refer to the scattering properties of an event, such as no scattering, single scattering, or multiple scattering. Therefore, based on the scattering characteristics of an event, events can be classified into no-scattering events, single-scattering events, and multiple-scattering events.

[0068] The first correction energy can be a pre-set standard correction energy, such as 511 keV. The gain correction factor is a gain factor used to perform basic linear scaling of the event energy after correction based on the scattering characteristics of the event and the preset first correction energy.

[0069] In step S106, the first correction coefficient is obtained by fitting the first correction energy, the preset background energy, and the corresponding energy measurement value.

[0070] The background energy is the sum of the energy contributions of all interference signals generated by non-target radiation sources when measuring the target radiation signal. It can be a pre-set standard interference energy for low-energy correction, used to correct the environmental background and the characteristic ray response of the detector material.

[0071] Since the background energy is the radioactivity of Lu (lutetium) in LYSO (yttrium lutetium silicate scintillation crystal), three peaks—88, 202, and 307—are generated during decay. The 88 peak is undetectable due to the minimum threshold limitation; therefore, in this embodiment, the preset background energy can be at least one of 202 keV and 307 keV. For example, the background energy can be 202 keV, 307 keV, or both.

[0072] The energy measurement value refers to the actual energy value corresponding to each standard energy peak measured during the calibration process. The first calibration coefficient is a nonlinear coefficient used for nonlinear calibration of event energy, obtained by fitting and calibrating the first calibration energy, the preset background energy, and the corresponding energy measurement value. It is also a uniformity coefficient used for cross-module consistency calibration of event energy.

[0073] In this embodiment, the first correction coefficient can be obtained by fitting the first correction energy, the preset background energy, and the corresponding energy measurement value.

[0074] In step S108, the corresponding second correction coefficient is obtained by fitting the first correction energy, the background energy, the preset second correction energy, and the corresponding energy measurement value.

[0075] The second correction energy is greater than the first correction energy. The second correction energy can be a pre-set high-energy correction energy, such as 1274 keV. The second correction coefficient is obtained by fitting and correcting the first correction energy, the background energy, the pre-set second correction energy, and the corresponding energy measurement value. It includes a nonlinear coefficient for nonlinear correction of the event energy, a uniformity coefficient for cross-module consistency correction of the event energy, and a scattering correction coefficient for scattering correction of the event energy. High-energy correction can be achieved based on this second correction coefficient.

[0076] In this embodiment, the corresponding second correction coefficient can be obtained by fitting the first correction energy, the background energy, the preset second correction energy, and the corresponding energy measurement value.

[0077] In step S110, according to the correction instruction, the energy correction of the event to be processed is performed using the gain correction coefficient and the first correction coefficient, or using the gain correction coefficient and the second correction coefficient.

[0078] The calibration command includes an indication of whether to perform high-energy calibration. Specifically, if the calibration command does not include an indication to perform high-energy calibration, energy calibration is performed on the event to be processed using a gain calibration factor and a first calibration factor. Conversely, if the calibration command includes an indication to perform high-energy calibration, energy calibration is performed on the event to be processed using a gain calibration factor and a second calibration factor.

[0079] In the aforementioned energy correction method, events obtained by scanning a target radiation source are acquired. Correction is performed based on the event's scattering characteristics and a preset first correction energy to obtain a corresponding gain correction coefficient. A fitting process is then performed based on the first correction energy, a preset background energy, and corresponding energy measurements to obtain another first correction coefficient. Finally, a fitting process is performed based on the first correction energy, the background energy, a preset second correction energy, and corresponding energy measurements to obtain a second correction coefficient. Then, according to the correction command, energy correction is performed on the event to be processed using either the gain correction coefficient and the first correction coefficient, or using both the gain correction coefficient and the second correction coefficient. Since the second correction coefficient is used for high-energy correction, this method can achieve high-energy correction, improving the calculation accuracy of the high-energy portion. Furthermore, different correction modes can be adapted to meet specific needs, enhancing the flexibility of the correction process.

[0080] In one exemplary embodiment, the gain correction coefficient may include a first gain coefficient. Then, as shown... Figure 2 As shown, in step S104, correction is performed based on the scattering characteristics of the event and a preset first correction energy to obtain the corresponding gain correction coefficient, which may specifically include:

[0081] In step S202, non-scattering events are determined based on the scattering characteristics of the events.

[0082] Here, a non-scattering event refers to an event in which no scattering occurs within the crystal. In this embodiment, by means of Na... 22 From the raw data collected by the source, all events are parsed out, and then events that did not scatter within the crystal, i.e., non-scattering events, are filtered out, while events that did scatter within the crystal are discarded.

[0083] In step S204, the first energy distribution spectrum for each channel in each detector is determined based on the first energy range of the no-scattering event.

[0084] The first energy range refers to the energy range corresponding to no-scattering events, which can be determined empirically, such as 0 to 500 keV. For all the no-scattering events determined above, their energy measurements (usually the pulse amplitude of the detector output or the number of ADC channels) are extracted. The energy measurements of all no-scattering events (e.g., energy range from 0 to energyMax, where energyMax represents the maximum measured value) are normalized to a preset range, i.e., the first energy range (e.g., 0 to 500 keV, which can be adjusted according to actual conditions). Then, the events are categorized according to detector and channel identifiers, generating the first energy distribution spectrum for each channel in each detector. Figure 3As shown, these are the first energy distribution spectra of different channels, where the horizontal axis represents the normalized energy value and the vertical axis represents the count of the corresponding energy. The no-scattering events of each channel fall into the corresponding bin according to their energy values, and the counts are accumulated.

[0085] In step S206, the first energy peak value corresponding to each channel is determined according to the first energy distribution spectrum of each channel.

[0086] After filtering the first energy distribution spectrum of each channel, the horizontal coordinate corresponding to the peak value in each first energy distribution spectrum can be determined, that is, the first energy peak value corresponding to each channel can be determined.

[0087] In step S208, the first energy peak corresponding to each channel is corrected based on the preset first correction energy to determine the first gain coefficient corresponding to each channel.

[0088] For example, such as Figure 3 As shown, if the abscissa corresponding to the peak value in the first energy distribution spectrum of a certain channel in a certain detector is peak1, then the first energy peak value of the channel is corrected based on the following formula (1):

[0089]

[0090] Where peak1 is the first energy peak value of a channel determined based on the first energy distribution spectrum of a certain channel, energyMax is the maximum value of the energy measurement value of the non-scattering event determined above, K is the first gain coefficient of the corresponding channel after correction, and 511 is the preset first correction energy.

[0091] Based on this, the first gain coefficient K corresponding to each channel can be determined, and the K value can be stored in the correction table to obtain the energy correction table of the first step.

[0092] The above embodiment determines the first gain coefficient K of each channel by correcting the peak position of the 511keV single-photon event without scattering events to a standard value, thereby eliminating the gain difference between channels.

[0093] In one exemplary embodiment, the gain correction coefficient may further include a second gain coefficient. Then, as shown... Figure 4 As shown, in step S104, correction is performed based on the scattering characteristics of the event and a preset first correction energy to obtain the corresponding gain correction coefficient, which may specifically include:

[0094] In step S402, a scattering event is determined based on the scattering characteristics of the event.

[0095] In this context, a primary scattering event occurs when a photon undergoes its first Compton scattering within the crystal, resulting in the deposition of energy in two adjacent crystal units, producing two spatially separated but time-dependent signals. In this embodiment, this is achieved by using Na… 22 In the raw data collected from the source, all events are parsed out, and then the events that have undergone one scattering, namely the one-scattering events, are selected and the other events are discarded.

[0096] In step S404, the energy of the primary scattering event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the primary scattering event.

[0097] The corrected energy is the sum of the energies from the two energy depositions. Since a 511keV photon may undergo Compton scattering within the crystal, resulting in two energy deposition points, the energy of each deposition point is corrected separately, and then summed to obtain the corrected energy of the scattering event.

[0098] Specifically, by determining the first channel corresponding to the first energy and the second channel corresponding to the second energy in a single scattering event; calculating the first product of the first gain coefficient corresponding to the first channel and the first energy; calculating the second product of the first gain coefficient corresponding to the second channel and the second energy; calculating the sum of the first product and the second product, and determining the sum as the corrected energy for the single scattering event.

[0099] For example, if the first energy corresponding to the first deposition point in a single scattering event is E1, and the corresponding channel is C H1 The first gain coefficient corresponding to this channel is K1, the second energy corresponding to the second deposition point is E2, and the corresponding channel is C. H2 If the first gain coefficient corresponding to this channel is K2, then the final corrected energy E is: E=E1×K1+E2×K2.

[0100] In step S406, based on the energy after correction of a single scattering event and a preset second energy range, a second energy distribution spectrum for each channel in each detector is determined.

[0101] The second energy range can be 300-900 keV. Specifically, for all single events with the corrected energy, they can be categorized according to the detector and channel identifiers corresponding to the events, generating the second energy distribution spectrum for each channel in each detector. For example... Figure 5 As shown, these are the second energy distribution spectra for different channels. The horizontal axis represents the normalized value of the corrected energy, and the vertical axis represents the count of the corresponding energy. Each scattering event of each channel falls into the corresponding bin according to the energy value, and the count is accumulated.

[0102] In step S408, the second energy peak value corresponding to each channel is determined according to the second energy distribution spectrum of each channel.

[0103] By filtering the second energy distribution spectrum of each channel, the horizontal coordinate corresponding to the peak value in each second energy distribution spectrum can be determined, that is, the second energy peak value corresponding to each channel can be determined.

[0104] In step S410, the second energy peak corresponding to each channel is corrected based on the preset first correction energy to determine the second gain coefficient corresponding to each channel.

[0105] For example, such as Figure 5 As shown, if the abscissa corresponding to the peak value in the second energy distribution spectrum of a certain channel in a certain detector is peak2, then the second energy peak value of the channel is corrected based on the following equation (2):

[0106]

[0107] Where peak2 is the second energy peak value of a channel determined based on the second energy distribution spectrum of a certain channel, 511 is the preset first correction energy, and K B2 This is the second gain coefficient for the corresponding channel after correction.

[0108] The above embodiments determine the second gain coefficient K of each channel by scaling the sum of the scattering events as a whole. B2 This is to correct the nonlinear response of the first scattering.

[0109] Based on this, the second gain coefficient K corresponding to each channel can be determined. B2 and K B2 Therefore, the calibration table includes the first gain coefficient K and the second gain coefficient K corresponding to each channel. B2 .

[0110] In one exemplary embodiment, the gain correction coefficient may further include a third gain coefficient. Then, as shown... Figure 6 As shown, in step S104, correction is performed based on the scattering characteristics of the event and a preset first correction energy to obtain the corresponding gain correction coefficient, which may specifically include:

[0111] In step S602, multiple scattering events are determined based on the scattering characteristics of the events.

[0112] Among them, multiple scattering events refer to any γ photon produced by positron annihilation undergoing two or more Compton scatterings before being finally captured by the detector.

[0113] In this embodiment, by using Na22 From the raw data collected from the source, all events are parsed out, and then the events that have undergone multiple scattering, namely the multiple scattering events, are selected and the other events are discarded.

[0114] In step S604, the energy of the multiple scattering event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the multiple scattering event.

[0115] The corrected energy is the sum of the energies from multiple energy depositions. Since a 511keV photon may undergo Compton scattering within a crystal, producing three or more energy deposition points, the corrected energy of each deposition point is obtained by correcting the energy of each point and then summing them.

[0116] Specifically, taking multiple scattering as three-stage scattering as an example, we can determine the first channel corresponding to the first energy, the second channel corresponding to the second energy, and the third channel corresponding to the third energy in the three-stage scattering. Then, we calculate the first product of the first gain coefficient corresponding to the first channel and the first energy; calculate the second product of the first gain coefficient corresponding to the second channel and the second energy; calculate the third product of the first gain coefficient corresponding to the third channel and the third energy; and calculate the sum of the first, second, and third products, and determine this sum as the energy after correction for the multiple scattering event.

[0117] For example, suppose the raw energies of an event measured in three channels are E1_raw, E2_raw, and E3_raw. Based on the channel identifier (IP, CH) of each deposition point, the K value (i.e., the first gain coefficient corresponding to each channel) is obtained by querying the aforementioned correction table. If the queried K value includes K1, K2, and K3, then the energy is corrected and summed. The final corrected energy E_total = (E1_raw × K1) + (E2_raw × K2) + (E3_raw × K3).

[0118] In step S606, based on the energy after correction of multiple scattering events and the preset third energy range, the third energy distribution spectrum for each detector is determined.

[0119] The third energy range can be 0-1000 keV. Specifically, for all single events with the corrected energy, they can be categorized according to the detector identifier corresponding to the event, generating the third energy distribution spectrum for each detector. Since the number of multiple scattering events in a single channel is too small to form a reliable peak position, this embodiment uses detector statistics to obtain the third energy distribution spectrum for each detector. Figure 7As shown, this is the third energy distribution spectrum of a certain detector, where the horizontal axis is the normalized value of the corrected energy and the vertical axis is the count of the corresponding energy. The multiple scattering events of each detector fall into the corresponding bin according to the energy value, and the count is accumulated at the same time.

[0120] In step S608, the third energy peak value corresponding to each detector is determined according to the third energy distribution spectrum of each detector.

[0121] By filtering the third energy distribution spectrum of each detector, the abscissa corresponding to the peak value in each third energy distribution spectrum can be determined, that is, the third energy peak value corresponding to each detector can be determined.

[0122] In step S610, the third energy peak corresponding to each detector is corrected based on the preset first correction energy to determine the third gain coefficient corresponding to each detector.

[0123] For example, such as Figure 7 As shown, if the abscissa corresponding to the peak in the third energy distribution spectrum of a certain detector is peak3, then correction can be performed based on the following equation (3):

[0124]

[0125] Where peak3 is the third energy peak value of the detector determined based on the third energy distribution spectrum of a certain detector, 511 is the preset first correction energy, and K B3 This is the third gain coefficient of the corresponding detector obtained after correction.

[0126] The above embodiments obtain the third gain coefficient K of each detector by scaling the sum of the energies of multiple scattering events as a whole. B3 This is to compensate for higher-order nonlinear effects.

[0127] Based on this, the third gain coefficient K corresponding to each detector can be determined. B3 and K B3 Therefore, the calibration table includes the first gain coefficient K and the second gain coefficient K corresponding to each channel. B2 And the third gain coefficient K of each detector B3 .

[0128] In one exemplary embodiment, such as Figure 8 As shown, in step S106, a fitting is performed based on the first correction energy, the preset background energy, and the corresponding energy measurement value to obtain the corresponding first correction coefficient. Specifically, this may include:

[0129] In step S802, a first energy measurement value corresponding to the first correction energy is determined, and a second energy measurement value corresponding to the background energy is determined.

[0130] The first energy measurement value is the actual energy value determined based on the energy distribution spectrum corresponding to the target data, and the first correction energy is the pre-set standard correction energy. The background energy is the pre-set standard interference energy for low-energy correction, and the second energy measurement value is the actual background energy determined based on the energy distribution spectrum corresponding to the air-collected data.

[0131] For example, the first energy measurement can be determined as follows: First, a non-scattering event is determined based on the scattering characteristics of the event. Specifically, by analyzing the scattering characteristics of Na... 22 In the raw data acquired by the source, all events are analyzed, and events that do not involve intracrystal scattering (i.e., non-scattering events) are selected and discarded. Then, the energy of the non-scattering events is corrected according to the first gain coefficient corresponding to each channel, yielding the corrected energy. Based on the corrected energy and a preset seventh energy range (e.g., 300-900 keV), the seventh energy distribution spectrum for each channel in each detector is determined; the first correction energy lies within the seventh energy range, for example, 511 keV. Next, based on the seventh energy distribution spectrum of each channel, the seventh energy peak value corresponding to each channel is determined, and this peak value is defined as the first energy measurement value corresponding to the first correction energy. Based on this, the first energy measurement value corresponding to the first correction energy in each channel can be determined.

[0132] For example, the second energy measurement value can be determined as follows: First, acquire the empty sampling events obtained from the empty sampling. Here, an empty sampling event refers to background data collected without a radioactive source, which typically includes the natural background gamma rays of Lu-176 in the detector crystal material (such as LYSO), with energies generally between 202 keV and 307 keV. From the empty sampling events, filter out non-scattering empty sampling events that do not involve intracrystal scattering, and discard empty sampling events that do involve intracrystal scattering.

[0133] Then, energy correction is performed on the no-scattering sampling event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the no-scattering sampling event. Based on the corrected energy of the no-scattering sampling event and the preset eighth energy range (e.g., 0-500keV), the eighth energy distribution spectrum for each channel in each detector is determined. Next, based on the eighth energy distribution spectrum of each channel and the background energy, the eighth energy peak value in each channel is determined; the eighth energy peak value of each channel is used as the corresponding second energy measurement value.

[0134] In this embodiment, taking background energies of 202 keV and 307 keV as examples, the eighth energy distribution spectrum is as follows: Figure 9 As shown, these are the eighth energy distribution spectra for different channels, where the horizontal axis represents the energy value and the vertical axis represents the count of the corresponding energy. For each channel, no-scattering empty sampling events are placed into the corresponding bin based on their energy values, and the counts are accumulated. Based on... Figure 9 By analyzing the eighth energy distribution spectrum, we can identify the two peak energies for each channel, namely the two eighth energy peaks, which correspond one-to-one with the two background energies. For example, for the channel identified as "IP3.14-SCH-CH1", its two eighth energy peaks are 246keV and 341keV, respectively. The eighth energy peak of 246keV corresponds to the second energy measurement value corresponding to the background energy of 202keV, and the eighth energy peak of 341keV corresponds to the second energy measurement value corresponding to the background energy of 307keV. Based on this, we can determine the second energy measurement values ​​corresponding to the background energies in each channel.

[0135] In step S804, based on the first correction energy, the first energy measurement value, the background energy, and the second energy measurement value, a preset first fitting function is fitted to obtain the first nonlinear coefficient.

[0136] The first fitting function can be as shown in equation (4):

[0137] y = P1 * X 2 +P2*X+P3, (4)

[0138] Where y is the standard energy (such as the first correction energy and two background energies), X is the corresponding energy measurement value, and P1, P2, and P3 are the first nonlinear coefficients. These first nonlinear coefficients are used to correct the oversaturation effect of sipm.

[0139] For example, by substituting the data X and y for each channel (such as the first correction energy 511 keV and its corresponding first energy measurement, the background energy 202 keV and its corresponding second energy measurement, and the background energy 307 keV and its corresponding second energy measurement) into the above fitting function for solution, the first nonlinear coefficients P1, P2, and P3 of the corresponding channel can be obtained. The first nonlinear coefficients of each channel can then be stored in the above correction table.

[0140] In step S806, axial consistency correction is performed based on the scattering characteristics of the event and the preset first correction energy to obtain the corresponding first uniformity correction coefficient.

[0141] Specifically, scattering events between detectors can be determined based on the scattering characteristics of the events. An inter-detector scattering event refers to a situation where a gamma photon first enters one detector crystal, undergoes Compton scattering, escapes the crystal, and then flies to another detector crystal where it is completely absorbed (resulting in the photoelectric effect). This process is recorded by the system as two interactions occurring within a coincidence time window in two different detector channels. In this embodiment, by using Na… 22 In the raw data collected from the source, all events are parsed out, and then scattering events that occur between detectors are selected, while other events are discarded.

[0142] Then, based on the above correction table, the energy of the scattering events between the selected detectors is corrected, and the peak energy corresponding to the target correction energy is determined according to the scattering events between each detector; wherein, the target correction energy can be the first correction energy, for example, 511 keV. For example, for the above corrected energy, a corresponding energy distribution spectrum can be generated, such as... Figure 10 As shown, the horizontal axis represents the corrected energy, and the vertical axis represents the count of the corresponding energy. By filtering this energy distribution spectrum, the horizontal axis corresponding to the peak value in the spectrum can be determined, i.e., the peak energy, and the peak energy corresponding to the target corrected energy can be found. Figure 10 It can be seen that there are multiple peaks, and the peak closest to the target correction energy can be determined as the corresponding peak energy.

[0143] Then, based on the target correction energy, such as the first correction energy and the corresponding peak energy, a preset fourth fitting function can be fitted.

[0144] The fourth fitting function can be as shown in equation (5):

[0145] y = K XA *X+K XB (5)

[0146] Where y is the standard energy (e.g., the first correction energy 511 keV), X is the corresponding energy peak, and K... XA and K XB This is the first uniformity correction coefficient obtained after fitting. The obtained first uniformity correction coefficient can then be stored in the correction table mentioned above. This first uniformity correction coefficient corrects for the response non-uniformity along the detector ring axis (depth direction) to compensate for gain differences between different ring layers.

[0147] In step S808, the corresponding first correction coefficient is determined based on the first nonlinear coefficient and the first uniformity correction coefficient.

[0148] Specifically, based on the first nonlinear coefficient and the first uniformity correction coefficient determined above, a corresponding first correction coefficient can be determined. That is, the first correction coefficient includes the aforementioned first nonlinear coefficient and first uniformity correction coefficient.

[0149] As can be seen from the above embodiments, the first correction coefficient is determined by stepwise correction based on the first correction energy and the background energy. It compensates for all systematic errors from crystal response, photoelectric conversion, electronic gain to photon scattering physical processes, thereby ensuring that no matter how photons deposit energy, the final measured total energy can accurately correspond to 511keV, thus improving the accuracy of correction.

[0150] In one exemplary embodiment, such as Figure 11 As shown, in step S108, a fitting process is performed based on the first correction energy, the background energy, and the preset second correction energy, along with the corresponding energy measurement values, to obtain the corresponding second correction coefficient. Specifically, this may include:

[0151] In step S1102, the first energy measurement value corresponding to the first correction energy is determined, the second energy measurement value corresponding to the background energy is determined, and the peak value of the non-scattering energy corresponding to the second correction energy is determined.

[0152] The process for determining the first energy measurement value and the second energy measurement value can be referred to the above. Figure 8 Step S802 of the illustrated embodiment will not be described again in this embodiment.

[0153] The second correction energy can be a pre-set high-energy correction energy, for example, the second correction energy can be 1274 keV. The no-scattering energy peak is the actual energy peak determined based on the energy distribution spectrum corresponding to events in which no intracrystal scattering events occurred.

[0154] For example, determining the peak value of the no-scattering energy corresponding to the second correction energy may specifically include: first, determining the no-scattering event based on the scattering characteristics of the event. Specifically, by analyzing the scattering characteristics of Na... 22 In the raw data acquired by the source, all events are analyzed, and events that do not involve intracrystal scattering (i.e., no-scattering events) are selected, while events involving intracrystal scattering are discarded. Then, the energy of the no-scattering events is corrected according to the first gain coefficient corresponding to each channel, yielding the corrected energy. Based on the corrected energy and a preset fourth energy range (e.g., 1000-1500 keV), the fourth energy distribution spectrum for each channel in each detector is determined. The second correction energy lies within this fourth energy range; for example, the first correction energy could be 1274 keV. The fourth energy distribution spectrum could be as follows: Figure 12As shown, the horizontal axis represents the corrected energy, and the vertical axis represents the corresponding energy count. By filtering this energy distribution spectrum, the horizontal axis corresponding to the peak values ​​in the spectrum can be determined (Peak is 371 and Peak is 392 in the figure), that is, the fourth energy peak value corresponding to each channel (i.e., the actual energy corresponding to the peak value) can be determined, and the fourth energy peak value corresponding to each channel can be determined as the non-scattered energy peak value corresponding to the second corrected energy. Based on this, the non-scattered energy measurement value corresponding to the second corrected energy in each channel can be determined.

[0155] In step S1104, based on the first corrected energy, the first energy measurement value, the background energy, the second energy measurement value, the second corrected energy, and the peak value of the non-scattered energy, a preset first fitting function is fitted to obtain the corresponding second nonlinear coefficient.

[0156] The first fitting function is shown in equation (4) above, and the fitting process described above can be referred to in detail. The difference is that, in this embodiment, based on the fitting of equation (4) above, a set of data X (i.e., the peak value of the non-scattering energy corresponding to the second correction energy) and y (i.e., the second correction energy, such as 1274keV) are added. That is, by substituting the four sets of data into the fitting function above, the second nonlinear coefficients P1, P2 and P3 of the corresponding channels are obtained. Then, the second nonlinear coefficients of each channel can be stored in the correction table above.

[0157] In step S1106, the peak value of the first scattering energy corresponding to the second correction energy is determined, and the preset second fitting function is fitted based on the second correction energy and the peak value of the first scattering energy to obtain the nonlinear correction coefficient of the first scattering.

[0158] The peak energy of a single scattering event is the actual peak energy determined based on the energy distribution spectrum corresponding to the event in which a single scattering event occurs within the crystal.

[0159] Specifically, determining the peak value of the primary scattering energy corresponding to the second correction energy can include: first, determining the primary scattering event based on the scattering characteristics of the event. For example, by analyzing the scattering characteristics of Na... 22 In the raw data acquired by the source, all events are analyzed, and then events that involve single scattering (i.e., single scattering events) are selected, while other events are discarded. Next, the energy of the single scattering events is corrected according to the first gain coefficient corresponding to each channel, yielding the corrected energy of the single scattering event. Based on the corrected energy of the single scattering event and a preset fifth energy range (e.g., 0-2000 keV), the fifth energy distribution spectrum for each channel in each detector is determined; where the second corrected energy lies within the fifth energy range. The fifth energy distribution spectrum can be as follows: Figure 13As shown, the horizontal axis represents the corrected energy, and the vertical axis represents the corresponding energy count. By filtering this energy distribution spectrum, the horizontal axis corresponding to the peak values ​​in the spectrum can be determined (Peak is 56 and Peak is 59 in the figure), that is, the fifth energy peak value corresponding to each channel (i.e., the actual energy corresponding to the peak value Peak) can be determined, and the fifth energy peak value corresponding to each channel can be determined as the first scattering energy peak value corresponding to the second corrected energy. Based on this, the measured value of the first scattering energy corresponding to the second corrected energy in each channel can be determined.

[0160] In this embodiment, after determining the peak value of the first scattering energy corresponding to the second correction energy, a preset second fitting function can be fitted based on the second correction energy and the peak value of the first scattering energy to obtain the nonlinear correction coefficient of the first scattering.

[0161] The second fitting function can be as shown in equation (6):

[0162] y = A² * X + B², (6)

[0163] Where y is the standard energy (e.g., the second correction energy of 1274 keV), X is the corresponding peak energy of the first scattering, and A2 and B2 are the first scattering nonlinearity correction coefficients obtained after fitting. These first scattering nonlinearity correction coefficients can then be stored in the aforementioned correction table. These coefficients are used to finely adjust the energy nonlinearity response in a first scattering event. A2 is the quadratic term coefficient, used to correct nonlinearity in the high-energy range, and B2 is the constant offset term, used to compensate for system background or energy zero-point drift.

[0164] In step S1108, the peak value of the multiple scattering energy corresponding to the second correction energy is determined, and the preset third fitting function is fitted based on the second correction energy and the peak value of the multiple scattering energy to obtain the multiple scattering nonlinear correction coefficient.

[0165] Among them, the peak energy of multiple scattering is the actual peak energy determined based on the energy distribution spectrum corresponding to the event in which multiple scattering occurs within the crystal.

[0166] Specifically, determining the peak value of the multiple scattering energy corresponding to the second correction energy can include: first, determining the multiple scattering event based on the scattering characteristics of the event. For example, this can be done by analyzing the Na... 22In the raw data acquired by the source, all events are analyzed, and then events that involve multiple scattering (i.e., multiple scattering events) are selected, while other events are discarded. Next, the energy of the multiple scattering events is corrected according to the first gain coefficient corresponding to each channel, resulting in the corrected energy of the multiple scattering events. Based on the corrected energy of the multiple scattering events and a preset sixth energy range (e.g., 1000-1500 keV), the sixth energy distribution spectrum for each detector is determined. The second corrected energy lies within the sixth energy range. The sixth energy distribution spectrum can be as follows: Figure 14 As shown, the horizontal axis represents the corrected energy, and the vertical axis represents the count of the corresponding energy. By filtering the energy distribution spectrum, the horizontal axis corresponding to the peak in the energy distribution spectrum can be determined (Peak is 12 in the figure), that is, the corresponding sixth energy peak (that is, the actual energy corresponding to the peak Peak), which is also the multi-scattering energy peak corresponding to the second corrected energy.

[0167] In this embodiment, after determining the peak value of the multiple scattering energy corresponding to the second correction energy, a preset third fitting function can be fitted based on the second correction energy and the peak value of the multiple scattering energy to obtain the multiple scattering nonlinear correction coefficient.

[0168] The third fitting function can be as shown in equation (7):

[0169] y = A3*X + B3, (6)

[0170] Where y is the standard energy (e.g., the second correction energy of 1274 keV), X is the corresponding peak energy of multiple scattering, and A3 and B3 are the multiple scattering nonlinearity correction coefficients obtained after fitting. These multiple scattering nonlinearity correction coefficients can then be stored in the aforementioned correction table. These multiple scattering nonlinearity correction coefficients are used to finely adjust the energy nonlinearity response in multiple scattering events. A3 is a cubic term coefficient used to correct nonlinearity in the high-energy range, and B3 is a constant offset term used to compensate for system background or energy zero-point drift.

[0171] In step S1110, axial consistency correction is performed based on the scattering characteristics of the event and the preset second correction energy to obtain the corresponding second uniformity correction coefficient.

[0172] Specifically, scattering events between detectors can be determined based on the scattering characteristics of the events. For example, by analyzing the scattering characteristics of Na... 22 In the raw data collected from the source, all events are parsed out, and then scattering events that occur between detectors are selected, while other events are discarded.

[0173] Then, based on the above correction table, the energy of the scattering events between the selected detectors is corrected, and the peak energy corresponding to the target correction energy is determined according to the scattering events between each detector; wherein, the target correction energy can be a second correction energy, such as 1274 keV. For example, for the above corrected energy, a corresponding energy distribution spectrum can be generated, such as... Figure 10 As shown, the horizontal axis represents the corrected energy, and the vertical axis represents the count of the corresponding energy. By filtering this energy distribution spectrum, the horizontal axis corresponding to the peak value in the spectrum can be determined, i.e., the peak energy, and the peak energy corresponding to the target corrected energy can be found. Figure 10 It can be seen that there are multiple peaks, and the peak closest to the target correction energy can be determined as the corresponding peak energy.

[0174] Furthermore, based on the target correction energy, such as the second correction energy, and the corresponding peak energy, a fourth fitting function as shown in equation (5) can be used for fitting. Where y is the standard energy (e.g., the second correction energy 1274 keV), X is the corresponding energy peak, and K... XA and K XB This is the second uniformity correction coefficient obtained after fitting. The obtained second uniformity correction coefficient can then be stored in the correction table mentioned above. This second uniformity correction coefficient corrects for the response non-uniformity along the detector ring axis (depth direction) to compensate for the high-energy gain differences between different ring layers.

[0175] In step S1112, the corresponding second correction coefficient is determined based on the second nonlinear coefficient, the single scattering nonlinear correction coefficient, the multiple scattering nonlinear correction coefficient, and the second uniformity correction coefficient.

[0176] Specifically, based on the second nonlinear coefficient, the single scattering nonlinear correction coefficient, the multiple scattering nonlinear correction coefficient, and the second uniformity correction coefficient determined above, the corresponding second correction coefficient can be determined. That is, the second correction coefficient includes the aforementioned second nonlinear coefficient, single scattering nonlinear correction coefficient, multiple scattering nonlinear correction coefficient, and second uniformity correction coefficient.

[0177] As can be seen from the above embodiments, the second correction coefficient is determined by stepwise correction based on the first correction energy, the background energy, and the second correction energy. It compensates for systematic errors across the entire spectrum, from crystal response, photoelectric conversion, and electronic gain to the photon scattering physical process. Furthermore, since the second correction energy is high-energy, it can correct the high-energy portion, making the high-energy portion more accurate.

[0178] For example, Figure 15A To verify the final energy spectrum obtained from the Na source data using the correction table (including the aforementioned gain correction coefficients and the first correction coefficient) obtained without high-energy correction,Figure 15B To verify the final energy spectrum obtained from the Na source data, a correction table (including the aforementioned gain correction coefficients and second correction coefficients) was used after high-energy correction. As shown in the figure, Figure 15B The high-energy portion of the calibration table (which verifies the energy spectrum of the Na source data by performing high-energy calibration) is more accurate (it is closer to the high-energy standard value of 1274 keV).

[0179] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps. It is understood that the steps in different embodiments can be freely combined as needed, and all non-contradictory solutions formed by such combinations are within the scope of protection of this application.

[0180] Based on the same inventive concept, this application also provides an energy correction device for implementing the energy correction method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more energy correction device embodiments provided below can be found in the limitations of the energy correction method described above, and will not be repeated here.

[0181] In one exemplary embodiment, such as Figure 16 As shown, an energy correction device is provided, including: an event acquisition module 1602, a gain determination module 1604, a first fitting module 1606, a second fitting module 1608, and a correction module 1610, wherein:

[0182] Event acquisition module 1602 is configured to acquire events obtained from scanning the target radiation source;

[0183] The gain determination module 1604 is configured to perform correction based on the scattering characteristics of the event and a preset first correction energy to obtain the corresponding gain correction coefficient.

[0184] The first fitting module 1606 is configured to perform fitting based on the first corrected energy, the preset background energy, and the corresponding energy measurement value to obtain the corresponding first correction coefficient.

[0185] The second fitting module 1608 is configured to perform fitting based on the first correction energy, the background energy, a preset second correction energy, and the corresponding energy measurement value to obtain a corresponding second correction coefficient; the second correction energy is greater than the first correction energy.

[0186] The correction module 1610 is configured to perform energy correction on the event to be processed according to a correction instruction, using the gain correction coefficient and the first correction coefficient, or using the gain correction coefficient and the second correction coefficient; the correction instruction includes an indication of whether to perform high-energy correction.

[0187] In an exemplary embodiment, the gain correction coefficient includes a first gain coefficient; then the gain determination module is further configured to perform: determining a no-scattering event based on the scattering characteristics of the event; determining a first energy distribution spectrum for each channel in each detector according to a first energy range of the no-scattering event; determining a first energy peak value corresponding to each channel according to the first energy distribution spectrum of each channel; correcting the first energy peak value corresponding to each channel based on a preset first correction energy, and determining a first gain coefficient corresponding to each channel.

[0188] In an exemplary embodiment, the gain correction coefficient further includes a second gain coefficient; then the gain determination module is further configured to perform: determining a primary scattering event based on the scattering characteristics of the event; performing energy correction on the primary scattering event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the primary scattering event; determining a second energy distribution spectrum for each channel in each detector based on the corrected energy of the primary scattering event and a preset second energy range; determining a second energy peak value corresponding to each channel according to the second energy distribution spectrum of each channel; and correcting the second energy peak value corresponding to each channel based on the preset first correction energy to determine a second gain coefficient corresponding to each channel.

[0189] In an exemplary embodiment, the gain determination module is further configured to perform: determining a first channel corresponding to a first energy and a second channel corresponding to a second energy in the primary scattering event; obtaining a first product of a first gain coefficient corresponding to the first channel and the first energy; obtaining a second product of a first gain coefficient corresponding to the second channel and the second energy; obtaining the sum of the first product and the second product, and determining the sum as the energy after correction for the primary scattering event.

[0190] In an exemplary embodiment, the gain correction coefficient further includes a third gain coefficient; then the gain determination module is further configured to perform: determining a multiple scattering event based on the scattering characteristics of the event; performing energy correction on the multiple scattering event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the multiple scattering event; determining a third energy distribution spectrum for each detector based on the corrected energy of the multiple scattering event and a preset third energy range; determining the third energy peak value corresponding to each detector according to the third energy distribution spectrum of each detector; and correcting the third energy peak value corresponding to each detector based on the preset first correction energy to determine the third gain coefficient corresponding to each detector.

[0191] In an exemplary embodiment, the gain determination module is further configured to perform: determining a first channel corresponding to a first energy, a second channel corresponding to a second energy, and a third channel corresponding to a third energy in the multiple scattering event; obtaining a first product of a first gain coefficient corresponding to the first channel and the first energy; obtaining a second product of a first gain coefficient corresponding to the second channel and the second energy; obtaining a third product of a first gain coefficient corresponding to the third channel and the third energy; obtaining the sum of the first product, the second product, and the third product, and determining the sum as the energy corrected for the multiple scattering event.

[0192] In an exemplary embodiment, the first fitting module is further configured to perform: determining a first energy measurement value corresponding to the first corrected energy, and determining a second energy measurement value corresponding to the background energy; fitting a preset first fitting function based on the first corrected energy, the first energy measurement value, the background energy, and the second energy measurement value to obtain a first nonlinear coefficient; performing axial consistency correction based on the scattering characteristics of the event and the preset first corrected energy to obtain a corresponding first uniformity correction coefficient; and determining a corresponding first correction coefficient based on the first nonlinear coefficient and the first uniformity correction coefficient.

[0193] In an exemplary embodiment, the second fitting module is further configured to perform: determining a first energy measurement value corresponding to the first corrected energy, determining a second energy measurement value corresponding to the background energy, and determining a peak value of no-scattering energy corresponding to the second corrected energy; fitting a preset first fitting function based on the first corrected energy, the first energy measurement value, the background energy, the second energy measurement value, the second corrected energy, and the peak value of no-scattering energy to obtain a corresponding second nonlinear coefficient; determining a peak value of primary scattering energy corresponding to the second corrected energy, fitting a preset second fitting function based on the second corrected energy and the peak value of primary scattering energy to obtain a primary scattering nonlinear correction coefficient; determining a peak value of multiple scattering energy corresponding to the second corrected energy, fitting a preset third fitting function based on the second corrected energy and the peak value of multiple scattering energy to obtain a multiple scattering nonlinear correction coefficient; performing axial consistency correction based on the scattering characteristics of the event and the preset second corrected energy to obtain a corresponding second uniformity correction coefficient; and determining a corresponding second correction coefficient based on the second nonlinear coefficient, the primary scattering nonlinear correction coefficient, the multiple scattering nonlinear correction coefficient, and the second uniformity correction coefficient.

[0194] In an exemplary embodiment, the second fitting module is further configured to perform: determining a no-scattering event based on the scattering characteristics of the event; performing energy correction on the no-scattering event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the no-scattering event; determining a fourth energy distribution spectrum for each channel in each detector based on the corrected energy of the no-scattering event and a preset fourth energy range; the second corrected energy being located within the fourth energy range; determining the fourth energy peak corresponding to each channel according to the fourth energy distribution spectrum of each channel; and determining the fourth energy peak corresponding to each channel as the no-scattering energy peak corresponding to the second corrected energy.

[0195] In an exemplary embodiment, the second fitting module is further configured to perform: determining a primary scattering event based on the scattering characteristics of the event; performing energy correction on the primary scattering event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the primary scattering event; determining the fifth energy distribution spectrum for each channel in each detector based on the corrected energy of the primary scattering event and a preset fifth energy range; the second corrected energy being located within the fifth energy range; determining the fifth energy peak value corresponding to each channel according to the fifth energy distribution spectrum of each channel; and determining the fifth energy peak value corresponding to each channel as the primary scattering energy peak value corresponding to the second corrected energy.

[0196] In an exemplary embodiment, the second fitting module is further configured to perform: determining multiple scattering events based on the scattering characteristics of the events; performing energy correction on the multiple scattering events according to the first gain coefficients corresponding to each channel to obtain the corrected energy of the multiple scattering events; determining a sixth energy distribution spectrum for each detector based on the corrected energy of the multiple scattering events and a preset sixth energy range; determining the sixth energy peak value corresponding to each detector according to the sixth energy distribution spectrum of each detector; and determining the sixth energy peak value corresponding to each detector as the multiple scattering energy peak value corresponding to the second corrected energy.

[0197] In an exemplary embodiment, determining the first energy measurement value corresponding to the first corrected energy includes: determining a no-scattering event based on the scattering characteristics of the event; performing energy correction on the no-scattering event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the no-scattering event; determining the seventh energy distribution spectrum for each channel in each detector based on the corrected energy of the no-scattering event and a preset seventh energy range; the first corrected energy being located within the seventh energy range; determining the seventh energy peak value corresponding to each channel according to the seventh energy distribution spectrum of each channel; and determining the seventh energy peak value corresponding to each channel as the first energy measurement value corresponding to the first corrected energy.

[0198] In an exemplary embodiment, determining the second energy measurement value corresponding to the background energy includes: acquiring an air sampling event obtained from air sampling; determining a non-scattering air sampling event based on the scattering characteristics of the air sampling event; performing energy correction on the non-scattering air sampling event according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the non-scattering air sampling event; determining the eighth energy distribution spectrum for each channel in each detector based on the corrected energy of the non-scattering air sampling event and a preset eighth energy range; determining the eighth energy peak value in each channel according to the eighth energy distribution spectrum of each channel and the background energy; and using the eighth energy peak value of each channel as the corresponding second energy measurement value.

[0199] In an exemplary embodiment, the axial consistency correction includes: determining scattering events between detectors based on the scattering characteristics of the events; determining a peak energy corresponding to a target correction energy based on the scattering events between detectors; the target correction energy includes a first correction energy or a second correction energy; and fitting a preset fourth fitting function based on the target correction energy and the corresponding peak energy.

[0200] In an exemplary embodiment, the correction module is further configured to perform: energy correction of the event to be processed using the gain correction coefficient and the first correction coefficient if it is determined that the correction instruction does not include an instruction to perform high-energy correction; and energy correction of the event to be processed using the gain correction coefficient and the second correction coefficient if it is determined that the correction instruction includes an instruction to perform high-energy correction.

[0201] In one exemplary embodiment, the target radioactive source is a radioactive isotope containing Na. 22 The radioactive source.

[0202] Each module in the aforementioned energy correction device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0203] In one exemplary embodiment, an electronic device is provided, the internal structure of which can be shown as follows: Figure 17 As shown, this electronic device includes a processor, memory, input / output interface, communication interface, display unit, and input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interface. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The input / output interface is used for exchanging information between the processor and external devices. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, Near Field Communication (NFC), or other technologies. When the computer program is executed by the processor, it implements an energy correction method. The display unit is used to form a visually visible image and can be a display screen, projection device, or virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the electronic device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads set on the casing of the electronic device, or external keyboards, touchpads, or mice, etc.

[0204] Those skilled in the art will understand that Figure 17The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the electronic device to which the present application is applied. The specific electronic device may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0205] In one exemplary embodiment, an electronic device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0206] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps in the above method embodiments.

[0207] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0208] 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, data stored, data displayed, 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 the relevant data must comply with relevant regulations.

[0209] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory 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 many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0210] The technical features of the above embodiments can be combined in any way. For the sake of brevity, 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 application.

[0211] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. An energy correction method, characterized in that, The method includes: Acquire events obtained from scanning a target radiation source; Based on the scattering characteristics of the event and the preset first correction energy, the corresponding gain correction coefficient is obtained; The first correction coefficient is obtained by fitting the first correction energy, the preset background energy, and the corresponding energy measurement value. A second correction coefficient is obtained by fitting the first correction energy, the background energy, the preset second correction energy, and the corresponding energy measurement value; the second correction energy is greater than the first correction energy. According to the calibration instruction, the gain calibration coefficient and the first calibration coefficient, or the gain calibration coefficient and the second calibration coefficient, are used to perform energy calibration on the event to be processed; the calibration instruction includes an indication of whether to perform high-energy calibration.

2. The method according to claim 1, characterized in that, The gain correction coefficient includes a first gain coefficient; The correction based on the scattering characteristics of the event and a preset first correction energy to obtain the corresponding gain correction coefficient includes: The non-scattering event is determined based on the scattering characteristics of the event; Based on the first energy range of the non-scattering event, determine the first energy distribution spectrum for each channel in each detector; Based on the first energy distribution spectrum of each channel, determine the first energy peak value corresponding to each channel; The first energy peak value corresponding to each channel is corrected based on the preset first correction energy to determine the first gain coefficient corresponding to each channel.

3. The method according to claim 2, characterized in that, The gain correction coefficient also includes a second gain coefficient; The correction based on the scattering characteristics of the event and a preset first correction energy to obtain the corresponding gain correction coefficient includes: A primary scattering event is determined based on the scattering characteristics of the event; The energy of the primary scattering event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the primary scattering event. Based on the energy after correction of the first scattering event and the preset second energy range, a second energy distribution spectrum for each channel in each detector is determined. Based on the second energy distribution spectrum of each channel, determine the second energy peak value corresponding to each channel; Based on the preset first correction energy, the second energy peak corresponding to each channel is corrected to determine the second gain coefficient corresponding to each channel.

4. The method according to claim 3, characterized in that, The step of performing energy correction on the primary scattering event based on the first gain coefficient corresponding to each channel to obtain the corrected energy of the primary scattering event includes: Determine the first channel corresponding to the first energy and the second channel corresponding to the second energy in the first scattering event; Obtain the first product of the first gain coefficient corresponding to the first channel and the first energy; Obtain the second product of the first gain coefficient corresponding to the second channel and the second energy; Obtain the sum of the first product and the second product, and determine the sum as the energy after correction for the first scattering event.

5. The method according to claim 2, characterized in that, The gain correction coefficient also includes a third gain coefficient; The correction based on the scattering characteristics of the event and a preset first correction energy to obtain the corresponding gain correction coefficient includes: Multiple scattering events are determined based on the scattering characteristics of the events; The energy of the multiple scattering event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the multiple scattering event. Based on the corrected energy of the multiple scattering events and the preset third energy range, a third energy distribution spectrum is determined for each detector. Based on the third energy distribution spectrum of each detector, determine the third energy peak value corresponding to each detector; The third energy peak corresponding to each detector is corrected based on the preset first correction energy to determine the third gain coefficient corresponding to each detector.

6. The method according to claim 5, characterized in that, The step of performing energy correction on the multiple scattering event based on the first gain coefficient corresponding to each channel to obtain the corrected energy of the multiple scattering event includes: Determine the first channel corresponding to the first energy, the second channel corresponding to the second energy, and the third channel corresponding to the third energy in the multiple scattering event; Obtain the first product of the first gain coefficient corresponding to the first channel and the first energy; Obtain the second product of the first gain coefficient corresponding to the second channel and the second energy; Obtain the third product of the first gain coefficient corresponding to the third channel and the third energy; Obtain the sum of the first product, the second product, and the third product, and determine the sum as the energy after correction for the multiple scattering event.

7. The method according to claim 2, characterized in that, The step of fitting the first corrected energy, the preset background energy, and the corresponding energy measurement value to obtain the corresponding first correction coefficient includes: Determine the first energy measurement value corresponding to the first correction energy, and determine the second energy measurement value corresponding to the background energy; Based on the first corrected energy, the first energy measurement value, the background energy, and the second energy measurement value, a preset first fitting function is fitted to obtain the first nonlinear coefficient; Based on the scattering characteristics of the event and the preset first correction energy, axial consistency correction is performed to obtain the corresponding first uniformity correction coefficient. Based on the first nonlinear coefficient and the first uniformity correction coefficient, the corresponding first correction coefficient is determined.

8. The method according to claim 2, characterized in that, The step of fitting the first corrected energy, the background energy, and the preset second corrected energy and the corresponding energy measurement value to obtain the corresponding second corrected coefficient includes: Determine the first energy measurement value corresponding to the first corrected energy, determine the second energy measurement value corresponding to the background energy, and determine the scatterless energy peak value corresponding to the second corrected energy; Based on the first corrected energy, the first energy measurement value, the background energy, the second energy measurement value, the second corrected energy, and the peak value of the non-scattered energy, a preset first fitting function is fitted to obtain the corresponding second nonlinear coefficient; Determine the peak value of the first scattering energy corresponding to the second correction energy, and fit a preset second fitting function based on the second correction energy and the peak value of the first scattering energy to obtain the nonlinear correction coefficient of the first scattering. Determine the peak value of the multiple scattering energy corresponding to the second correction energy, and fit a preset third fitting function based on the second correction energy and the peak value of the multiple scattering energy to obtain the multiple scattering nonlinearity correction coefficient; Based on the scattering characteristics of the event and the preset second correction energy, axial consistency correction is performed to obtain the corresponding second uniformity correction coefficient. The corresponding second correction coefficient is determined based on the second nonlinear coefficient, the single scattering nonlinear correction coefficient, the multiple scattering nonlinear correction coefficient, and the second uniformity correction coefficient.

9. The method according to claim 8, characterized in that, Determining the peak value of the non-scattering energy corresponding to the second corrected energy includes: The non-scattering event is determined based on the scattering characteristics of the event; The energy of the non-scattering event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the non-scattering event. Based on the energy corrected for the no-scattering event and the preset fourth energy range, the fourth energy distribution spectrum for each channel in each detector is determined; the second corrected energy is located within the fourth energy range. Based on the fourth energy distribution spectrum of each channel, determine the fourth energy peak value corresponding to each channel; The fourth energy peak corresponding to each channel is determined as the non-scattering energy peak corresponding to the second correction energy.

10. The method according to claim 8, characterized in that, Determining the peak value of the first scattering energy corresponding to the second corrected energy includes: A primary scattering event is determined based on the scattering characteristics of the event; The energy of the primary scattering event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the primary scattering event. Based on the energy corrected for the first scattering event and the preset fifth energy range, the fifth energy distribution spectrum for each channel in each detector is determined; the second corrected energy is located within the fifth energy range. Based on the fifth energy distribution spectrum of each channel, determine the fifth energy peak value corresponding to each channel; The fifth energy peak corresponding to each channel is determined as the first scattering energy peak corresponding to the second correction energy.

11. The method according to claim 8, characterized in that, Determining the peak value of the multiple scattering energy corresponding to the second corrected energy includes: Multiple scattering events are determined based on the scattering characteristics of the events; The energy of the multiple scattering event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the multiple scattering event. Based on the corrected energy of the multiple scattering events and the preset sixth energy range, the sixth energy distribution spectrum for each detector is determined. Based on the sixth energy distribution spectrum of each detector, determine the sixth energy peak value corresponding to each detector; The sixth energy peak corresponding to each detector is determined as the multi-scattering energy peak corresponding to the second correction energy.

12. The method according to claim 7 or 8, characterized in that, Determining the first energy measurement value corresponding to the first correction energy includes: The non-scattering event is determined based on the scattering characteristics of the event; The energy of the non-scattering event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the non-scattering event. Based on the energy after correction for the no-scattering event and the preset seventh energy range, the seventh energy distribution spectrum for each channel in each detector is determined; the first corrected energy is located within the seventh energy range. Based on the seventh energy distribution spectrum of each channel, determine the seventh energy peak value corresponding to each channel; The seventh energy peak value corresponding to each channel is determined as the first energy measurement value corresponding to the first correction energy.

13. The method according to claim 7 or 8, characterized in that, Determining the second energy measurement value corresponding to the background energy includes: Obtain the empty sampling events obtained from the empty sampling, and determine the non-scattering empty sampling events based on the scattering characteristics of the empty sampling events; The energy of the non-scattering air sampling event is corrected according to the first gain coefficient corresponding to each channel to obtain the corrected energy of the non-scattering air sampling event. Based on the energy corrected for the non-scattering empty sampling event and the preset eighth energy range, the eighth energy distribution spectrum for each channel in each detector is determined. Based on the eighth energy distribution spectrum of each channel and the background energy, determine the eighth energy peak value in each channel; The eighth energy peak value of each channel is used as the corresponding second energy measurement value.

14. The method according to claim 7 or 8, characterized in that, The axial consistency correction includes: The scattering events between the detectors are determined based on the scattering characteristics of the events. The peak energy corresponding to the target correction energy is determined based on the scattering events between each detector; the target correction energy includes either the first correction energy or the second correction energy. Based on the target correction energy and the corresponding peak energy, a preset fourth fitting function is fitted.

15. The method according to claim 1, characterized in that, The step of performing energy correction on the event to be processed according to the correction instruction, using the gain correction coefficient and the first correction coefficient, or using the gain correction coefficient and the second correction coefficient, includes: If it is determined that the correction instruction does not include an instruction to perform high-energy correction, the energy correction of the event to be processed is performed using the gain correction coefficient and the first correction coefficient. If it is determined that the correction instruction includes an instruction to perform high-energy correction, the event to be processed is energy corrected using the gain correction coefficient and the second correction coefficient.

16. The method according to claim 1, characterized in that, The target radioactive source is containing the radioactive isotope Na. 22 The radioactive source.

17. An energy correction device, characterized in that, include: The event acquisition module is configured to acquire events obtained from scanning the target radiation source; The gain determination module is configured to perform correction based on the scattering characteristics of the event and a preset first correction energy to obtain the corresponding gain correction coefficient; The first fitting module is configured to perform fitting based on the first corrected energy, a preset background energy, and the corresponding energy measurement value to obtain the corresponding first correction coefficient; The second fitting module is configured to perform fitting based on the first correction energy, the background energy, a preset second correction energy, and the corresponding energy measurement value to obtain a corresponding second correction coefficient; the second correction energy is greater than the first correction energy. The calibration module is configured to perform energy calibration on the event to be processed according to a calibration instruction, using the gain calibration coefficient and the first calibration coefficient, or using the gain calibration coefficient and the second calibration coefficient; the calibration instruction includes an indication of whether to perform high-energy calibration.

18. An electronic device comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 16.

19. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 16.

20. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 16.

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