A method for evaluating the biological effective dose of targeted α-radionuclide therapy based on microdosimetry

Abstract

This application proposes a method for assessing the bioeffective dose of targeted alpha radionuclide therapy based on microdosimetry. The method includes: integrating the time-activity curve of the alpha radionuclide in an organ to obtain the cumulative activity; calculating the physical absorbed dose and dose rate of the organ using Monte Carlo simulation; constructing a micro-dose spectrum of the alpha radionuclide based on micro-dose Monte Carlo simulation to obtain the saturated corrected dose-mean linear energy used to characterize radiation quality; using a micro-dose kinetic model, fitting the saturated corrected dose-mean linear energy with cell experimental data to obtain the biological effect parameters of the alpha radionuclide; and combining the physical absorbed dose, dose rate, and biological effect parameters to assess the bioeffective dose of the target organ. This application addresses the problem of the lack of a method for assessing the bioeffective dose in dose evaluation for targeted alpha radionuclide therapy.

Description

Technical Field

[0001] This application relates to the field of targeted alpha radionuclide therapy technology, and in particular to a method for evaluating the bioeffective dose of targeted alpha radionuclide therapy based on microdosimetry. Background Technology

[0002] Alpha-radioactive prostate-specific membrane antigen (PSMA) labeled with radionuclides has shown promising efficacy in targeted therapy for metastatic refractory prostate cancer (mCRPC). Compared to beta rays, alpha rays have a shorter range, and the alpha radionuclides accumulated within the tumor have less impact on surrounding normal tissues; alpha rays have a higher LET (Left-to-Tear) than beta rays, resulting in a stronger killing effect on tumor cells; furthermore, clinical findings have also shown... 225 Ac-PSMA-617 can overcome patients' [fear / proneness / fear]. 177 Resistance to Lu-PSMA-617 and its hematologic toxicity have made targeted alpha radiotherapy an important area of ​​research. The radiation dose to tumors or normal tissues directly affects treatment efficacy and side effects; therefore, dose assessment in targeted alpha radionuclide therapy is crucial.

[0003] In dose assessment of targeted alpha radionuclide therapy, the physical absorbed dose is insufficient to describe the biological effects of alpha particles because the energy deposition of high-LET alpha particles is more concentrated. Therefore, it is necessary to establish a method for assessing the bioeffective dose of targeted alpha radionuclide therapy.

[0004] However, existing dose calculation studies for targeted alpha radionuclide therapy use fixed values ​​for relative biological effects or rely on empirical formulas, failing to reflect the influence of factors such as cell type, radiation dose, and dose rate. Furthermore, existing dose assessment methods for targeted alpha radionuclide therapy fail to link the microscopic energy deposition characteristics of alpha particles with macroscopic biological effects, lacking methods for assessing bioeffective doses. Summary of the Invention

[0005] This application aims to at least partially address one of the technical problems in the related art.

[0006] Therefore, the first objective of this application is to propose a method for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry.

[0007] The second objective of this application is to provide a device for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry.

[0008] The third objective of this application is to propose an electronic device.

[0009] The fourth objective of this application is to provide a computer-readable storage medium.

[0010] The fifth objective of this application is to provide a computer program product.

[0011] To achieve the above objectives, the first aspect of this application proposes a method for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry, comprising:

[0012] The cumulative activity was obtained by integrating the time-activity curves of alpha radionuclides in organs, and the physical absorbed dose and dose rate of organs were calculated by Monte Carlo simulation.

[0013] Based on microdose Monte Carlo simulation, a microdose spectrum of alpha radionuclides was constructed, and the saturated corrected dose-averaged linear energy used to characterize radiation quality was obtained.

[0014] Using a micro-dose kinetic model, the biological effect parameters of the α-radioactive nuclide were obtained by fitting the saturated corrected dose mean line energy with cell experimental data.

[0015] The bioeffective dose to the target organ is evaluated by combining the physical absorbed dose, the dose rate, and the biological effect parameters.

[0016] Optionally, the step of integrating the time-activity curve of the alpha radionuclide in the target organ to obtain the cumulative activity, and calculating the physical absorbed dose and dose rate of the organ through Monte Carlo simulation, includes:

[0017] The cumulative activity is obtained by integrating the time-activity curves of alpha radionuclides in organs.

[0018] The cumulative activity was used as the source term in the Monte Carlo dose simulation to calculate the physical absorbed dose of the organ.

[0019] The dose rate is calculated using the following formula:

[0020]

[0021] in, A is the dose rate of target organ k at time t. i (t) represents the activity of the radionuclide in source organ i at time t, S i→k It is the conversion factor from the unit activity of source organ i to the absorbed dose of target organ k.

[0022] Optionally, the step of constructing the microdose spectrum of the alpha radionuclide based on microdose Monte Carlo simulation to obtain the saturated corrected dose-averaged linear energy used to characterize radiation quality includes:

[0023] The decay of alpha radionuclides was simulated using Monte Carlo simulation software, and the location and energy of all energy deposited for each incident particle were recorded.

[0024] One energy deposition is randomly selected and all energy depositions in the surrounding sensitive volume are counted. The linear energy y is calculated by dividing by the average chord length of the sensitive volume, and a micro-dose spectrum f(y) is generated based on the linear energy distribution.

[0025] Based on the microdose spectrum f(y), the saturated-corrected dose-averaged linear energy y is calculated. * The expression is:

[0026]

[0027] Where y0 is a saturation parameter, which is related to the sensitive volume geometry, cell nuclear radius, and biological effect parameter β.

[0028] Optionally, the step of combining the saturated corrected dose-average line with cell experimental data and using a microdose kinetic model to fit the biological effect parameters of the α-radioactive nuclide includes:

[0029] The relationship between cell viability fraction S and absorbed dose D is fitted using the following formula:

[0030]

[0031] Among them, α and β are biological effect parameters related to cell type and radiation type, respectively;

[0032] The expression for calculating the biological effect parameter α is as follows:

[0033]

[0034] Where α0 is the initial biological effect parameter, R n Let r be the radius of the cell nucleus, ρ be the density of the cell nucleus, and r be the density of the cell nucleus. d The average chord length of the sensitive volume.

[0035] Optional, also includes:

[0036] For the cell cluster model used to simulate micro-dose of alpha radionuclides, the simulated cell consists of three concentric spheres with different radii, which are respectively divided into the nucleus, cytoplasm and cell membrane;

[0037] The simulated cells in the cell cluster model are uniformly arranged in three-dimensional space.

[0038] Optionally, in the micro-dose Monte Carlo simulation, the decay location of the alpha radionuclide can be set in four ways: uniformly distributed within the cell, uniformly distributed in the cytoplasm, uniformly distributed in the intercellular space, and uniformly distributed throughout the entire cell cluster model.

[0039] Optionally, the assessment of the bioeffective dose to the target organ by combining the physically absorbed dose, the dose rate, and the biological effect parameters includes:

[0040] The effective biological dose is calculated using the following formula:

[0041]

[0042] Wherein, BED is the bioeffective dose, and G(T) is a factor describing the effect of dose rate on the biological effects of radiation, calculated as follows:

[0043]

[0044] Where μ is the repair coefficient.

[0045] To achieve the above objectives, a second aspect of this application provides a device for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry, comprising:

[0046] The physical dose simulation module is used to integrate the time-activity curve of alpha radionuclides in organs to obtain the cumulative activity, and to calculate the physical absorbed dose and dose rate of organs through Monte Carlo simulation.

[0047] The microdose spectrum generation module is used to construct the microdose spectrum of alpha radionuclides based on microdose Monte Carlo simulation, and obtain the saturated corrected dose average linear energy used to characterize radiation quality.

[0048] The biological effect parameter fitting module is used to obtain the biological effect parameters of the α-radioactive nuclide by fitting the saturated corrected dose mean line energy with cell experimental data using a micro-dose kinetic model.

[0049] A bioeffective dose calculation module is used to evaluate the bioeffective dose of a target organ by combining the physical absorbed dose, the dose rate, and the biological effect parameters.

[0050] To achieve the above objectives, a third aspect of this application provides an electronic device, including: a processor, and a memory communicatively connected to the processor;

[0051] The memory stores computer-executed instructions;

[0052] The processor executes computer execution instructions stored in the memory to implement the method as described in any one of the first aspects.

[0053] To achieve the above objectives, a fourth aspect of this application provides a computer-readable storage medium storing computer-executable instructions that, when executed by a processor, are used to implement the method as described in any one of the first aspects.

[0054] To achieve the above objectives, a fifth aspect of this application provides a computer program product that, when executed by a processor, implements the method described in any one of the first aspects.

[0055] The technical solutions provided by the embodiments of this application bring at least the following beneficial effects:

[0056] (1) This application overcomes the technical bottleneck of the lack of a bioeffective dose assessment method for targeted alpha radionuclide therapy in the prior art, and constructs a comprehensive assessment system that combines macroscopic and microscopic scales. By combining organ-level Monte Carlo simulation and cell-level micro-dose kinetic model, a precise assessment method is provided, which provides a scientific basis for the optimized design and application of alpha radionuclide therapy.

[0057] (2) This application utilizes micro-dose Monte Carlo simulation to establish the micro-dose spectrum of α particles in the cell nucleus and fits a micro-dose kinetic model to accurately calculate biological effect parameters (such as α and β parameters) for different cell types. This method effectively reflects the biological effects of α radionuclides at the cellular level, filling the technical gap that traditional physical dose assessment cannot characterize microscopic biological effects.

[0058] (3) The evaluation method of this application can comprehensively reflect the influence of factors such as cell type, radiation dose and dose rate on the effective biological dose, and provides a more detailed and scientific dosimetric analysis. This multi-factor comprehensive analysis method significantly improves the accuracy and personalization of alpha radionuclide therapy, laying the foundation for achieving more efficient and safer targeted radiotherapy.

[0059] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0060] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0061] Figure 1 A schematic flowchart illustrating a method for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry, provided in an embodiment of this application.

[0062] Figure 2A schematic flowchart illustrating a method for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry, provided in an embodiment of this application.

[0063] Figure 3 This is a schematic diagram of a cell cluster model for micro-dose simulation provided in an embodiment of this application;

[0064] Figure 4 This is a schematic diagram of a device for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry, provided in an embodiment of this application. Detailed Implementation

[0065] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0066] Existing studies on dose calculation for targeted alpha radionuclide therapy use fixed values ​​for relative biological effects or rely on empirical formulas, failing to reflect the influence of factors such as cell type, radiation dose, and dose rate. Furthermore, existing dose assessment methods for targeted alpha radionuclide therapy fail to link the microscopic energy deposition characteristics of alpha particles with macroscopic biological effects, lacking methods for assessing bioeffective doses.

[0067] To address this issue, this application provides a method for assessing the bioeffective dose of targeted alpha radionuclide therapy based on microdoscopy. Monte Carlo simulations are performed at the organ level to obtain the organ's absorbed dose and absorption rate. Simultaneously, microdoscopy simulations of the alpha radionuclide are performed at the cellular level to obtain the microdosage spectrum in the cell nucleus. For different cell types, microdoscopy kinetic models are fitted to obtain the biological effect parameters of different cells, thereby assessing the organ's bioeffective dose (BED). This solves the problem of the lack of a bioeffective dose assessment method in the dose evaluation of targeted alpha radionuclide therapy.

[0068] Figure 1 and Figure 2 This is a schematic flowchart illustrating a method for evaluating the effective biological dose of targeted alpha radionuclide therapy based on microdosimetry, provided in an embodiment of this application. Figure 1 As shown, the method includes the following steps:

[0069] Step 101: Integrate the time-activity curve of the alpha radionuclide in the organ to obtain the cumulative activity, and calculate the physical absorbed dose and dose rate of the organ through Monte Carlo simulation.

[0070] In this embodiment, the time-activity curve of the α-radionite in the organ is first integrated to obtain the cumulative activity. Then, the cumulative activity is used as the source term in the Monte Carlo dose simulation to calculate the physical absorbed dose of the organ. Furthermore, the dose rate simulation of the target organ k is calculated using the following formula:

[0071]

[0072] in, A is the dose rate of target organ k at time t. i (t) represents the activity of the radionuclide in source organ i at time t, S i→k It is the conversion factor from the unit activity of source organ i to the absorbed dose of target organ k.

[0073] Step 102: Based on micro-dose Monte Carlo simulation, construct the micro-dose spectrum of α-radioactive nuclide to obtain the saturated corrected dose-averaged linear energy used to characterize radiation quality.

[0074] In this embodiment, Monte Carlo simulation software is used to simulate the decay of alpha radionuclides and record the location and energy of all energy deposited for each incident particle.

[0075] In one possible embodiment, micro-dose simulation of alpha rays can be performed using the calculation program of NASIC, a nano-dose Monte Carlo simulation software developed by our laboratory, and the location and energy of all energy deposition for each incident particle can be recorded by adding micro-dose spectrum statistics to the physics module of NASIC.

[0076] Then, one energy deposition is randomly selected and all energy depositions in the surrounding sensitive volume are counted. The linear energy y is calculated by dividing by the average chord length of the sensitive volume, and a micro-dose spectrum f(y) is generated based on the linear energy distribution.

[0077] Furthermore, based on the microdose spectrum f(y), the dose-averaged linear energy y is used to calculate the saturation-corrected value. * The expression is:

[0078]

[0079] Where y0 is the saturation parameter, which is related to the sensitive volume geometry, cell nuclear radius, and biological effect parameter β, and its expression is:

[0080]

[0081] Among them, R n Let r be the radius of the cell nucleus, ρ be the density of the cell nucleus, and r be the density of the cell nucleus. d The average chord length of the sensitive volume.

[0082] It should be noted that the dose-average line can...* This demonstrates the impact of heavy ion radiation quality on cell survival.

[0083] In this embodiment, a cell cluster model is constructed in NASIC, and micro-dose simulation of alpha radionuclides is performed. (Refer to...) Figure 3 The model cell consists of three concentric spheres with radii of 5.5 μm, 9.9 μm, and 10.0 μm, respectively, which delineate the nucleus, cytoplasm, and cell membrane. Furthermore, the simulated cells in the cell cluster model are uniformly arranged in the x, y, and z directions of three-dimensional space.

[0084] Furthermore, to investigate the influence of the nucleus's distribution location on the microdose distribution within the cell nucleus, four decay locations for the alpha radionuclide were configured in the microdose Monte Carlo simulation: uniform distribution within the cell, uniform distribution in the cytoplasm, uniform distribution in the intercellular spaces, and uniform distribution throughout the entire cell cluster model. The linear energy of the radiation generated by each decay of the parent or daughter nucleus in the decay chain was individually calculated, thus obtaining the microdose spectrum of the entire decay chain. This spectrum was then input into the microdose kinetic model, and the parameters of the microdose kinetic model were iteratively optimized using the least squares method based on cell experimental data, thereby obtaining the biological effect parameters α and β of the alpha radionuclide.

[0085] Step 103: Using a micro-dose kinetic model, the biological effect parameters of the α-radioactive nuclide are obtained by fitting the saturated corrected dose-average linear energy with cell experimental data.

[0086] In this embodiment, the microdose kinetic model (MKM) used is a radiation biological effect model based on the theory of dual radiation effects established by the Japanese National Institutes of Health (NIRS), which is widely used in the evaluation of the biological effects of proton and heavy ion radiotherapy.

[0087] In this micro-dose kinetic model, the relationship between cell viability fraction S and absorbed dose D is fitted using the following formula:

[0088]

[0089] Here, α and β are biological effect parameters related to cell type and radiation type, respectively.

[0090] The expression for calculating the biological effect parameter α is as follows:

[0091]

[0092] Where α0 is the initial biological effect parameter, R n Let r be the radius of the cell nucleus, ρ be the density of the cell nucleus, and r be the density of the cell nucleus. d The average chord length of the sensitive volume.

[0093] In this embodiment, the micro-dose kinetic model was refitted using existing multi-set monoenergetic alpha-ray cell experimental data. The cell data were obtained from the PIDE database, including 27 sets of alpha-ray irradiated isolated V79 cells (Chinese hamster cells) and 6 sets of alpha-ray irradiated isolated Renca cells (mouse kidney cancer cells).

[0094] Step 104: Combine physical absorbed dose, dose rate, and biological effect parameters to assess the bioeffective dose to the target organ.

[0095] In this embodiment of the application, the bioeffective dose (BED) is calculated based on the results of macroscopic physical dose simulation and microscopic microdose simulation, according to the following formula:

[0096]

[0097] Where BED is the bioeffective dose, α and β are biological effect parameters obtained from microdose simulation, and G(T) is a factor describing the effect of dose rate on radiation biological effects, calculated as follows:

[0098]

[0099] Where μ is the repair coefficient.

[0100] To achieve the above embodiments, this application also proposes a device for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry. Figure 4 This is a schematic diagram of a device 10 for evaluating the effective dose of targeted alpha radionuclide therapy based on microdosimetry, provided as an embodiment of this application. Figure 4 As shown, the device includes:

[0101] The physical dose simulation module 100 is used to integrate the time-activity curve of alpha radionuclides in organs to obtain the cumulative activity, and to calculate the physical absorbed dose and dose rate of organs through Monte Carlo simulation.

[0102] The microdose spectrum generation module 200 is used to construct the microdose spectrum of α-radionuclides based on microdose Monte Carlo simulation, and obtain the saturated corrected dose average linear energy used to characterize radiation quality.

[0103] The biological effect parameter fitting module 300 is used to obtain the biological effect parameters of α-radioactive nuclides by fitting the saturated corrected dose mean line energy with cell experimental data using a micro-dose kinetic model.

[0104] The bioeffective dose calculation module 400 is used to assess the bioeffective dose of a target organ by combining physical absorbed dose, dose rate and biological effect parameters.

[0105] To implement the above embodiments, this application also proposes an electronic device, including: a processor and a memory communicatively connected to the processor; the memory stores computer execution instructions; the processor executes the computer execution instructions stored in the memory to implement the method provided in the foregoing embodiments.

[0106] To implement the above embodiments, this application also proposes a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the methods provided in the foregoing embodiments.

[0107] To implement the above embodiments, this application also proposes a computer program product, including a computer program that, when executed by a processor, implements the methods provided in the foregoing embodiments.

[0108] The collection, storage, use, processing, transmission, provision, and disclosure of user personal information involved in this application comply with relevant laws and regulations and do not violate public order and good morals.

[0109] It should be noted that personal information collected from users should be used for legitimate and reasonable purposes and should not be shared or sold outside of these legitimate uses. Furthermore, such collection / sharing should only be conducted after receiving the user's informed consent, including but not limited to notifying the user to read the user agreement / user notice and sign an agreement / authorization that includes authorization of relevant user information before the user uses the function. In addition, any necessary steps must be taken to protect and safeguard access to such personal information data and ensure that others with access to personal information data comply with their privacy policies and procedures.

[0110] This application is intended to provide an implementation scheme for users to selectively prevent the use or access to their personal information data. Specifically, this disclosure is intended to provide hardware and / or software to prevent or block access to such personal information data. Once personal information data is no longer needed, risks can be minimized by restricting data collection and deleting data. Furthermore, where applicable, such personal information is de-identified to protect user privacy.

[0111] In the foregoing descriptions of the embodiments, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0112] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0113] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0114] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0115] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0116] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0117] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0118] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

[0119] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this application can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this application can be achieved, and this is not limited herein.

[0120] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for evaluating the effective biological dose of targeted alpha radionuclide therapy based on microdosimetry, characterized in that, Includes the following steps: The cumulative activity was obtained by integrating the time-activity curves of alpha radionuclides in organs, and the physical absorbed dose and dose rate of organs were calculated by Monte Carlo simulation. Based on microdose Monte Carlo simulation, a microdose spectrum of alpha radionuclides was constructed, and the saturated corrected dose-averaged linear energy used to characterize radiation quality was obtained. Using a micro-dose kinetic model, the biological effect parameters of the α-radioactive nuclide were obtained by fitting the saturated corrected dose mean line energy with cell experimental data. The bioeffective dose to the target organ is evaluated by combining the physical absorbed dose, the dose rate, and the biological effect parameters. The evaluation of the bioeffective dose to the target organ by combining the physically absorbed dose, the dose rate, and the biological effect parameters includes: The effective biological dose is calculated using the following formula: in, This is the biologically effective dose. For absorbed dose, and These are biological effect parameters related to cell type and type of radiation. This is a factor describing the effect of dose rate on the biological effects of radiation, and its calculation formula is: in, The repair coefficient is... It is the conversion factor from the unit activity of source organ i to the absorbed dose of target organ k. It is the activity of radionuclides in source organ i at time t.

2. The method according to claim 1, characterized in that, The process involves integrating the time-activity curves of alpha radionuclides in the organ to obtain the cumulative activity, and then calculating the physical absorbed dose and dose rate of the organ using Monte Carlo simulation, including: The cumulative activity is obtained by integrating the time-activity curves of alpha radionuclides in organs. The cumulative activity was used as the source term in the Monte Carlo dose simulation to calculate the physical absorbed dose of the organ. The dose rate is calculated using the following formula: in, It is the dose rate of target organ k at time t. It is the activity of radionuclides in source organ i at time t. It is the conversion factor from the unit activity of source organ i to the absorbed dose of target organ k.

3. The method according to claim 2, characterized in that, The method, based on micro-dose Monte Carlo simulation, constructs the micro-dose spectrum of the alpha radionuclide to obtain the saturated corrected dose-averaged linear energy used to characterize radiation quality, including: The decay of alpha radionuclides was simulated using Monte Carlo simulation software, and the location and energy of all energy deposited for each incident particle were recorded. Randomly select one energy deposition and count all energy depositions within the surrounding sensitive volume. Divide the result by the average chord length of the sensitive volume to calculate the linear energy. And generate micro-dose spectrum based on linear energy distribution. ; Based on the micro-dose spectrum Calculate the saturated corrected dose-averaged linear energy The expression is: in, The saturation parameter is related to the sensitive volume geometry, cell nuclear radius, and biological effect parameters. Related.

4. The method according to claim 3, characterized in that, The method employs a micro-dose kinetic model, fitting the saturated corrected dose-average energy with cell experimental data to obtain the biological effect parameters of the α-radioactive nuclide, including: The cell survival score was fitted using the following formula. With absorbed dose The relationship between them can be expressed as: in, and These are biological effect parameters related to cell type and type of radiation; Among them, biological effect parameters The calculation expression is: in, These are the initial biological effect parameters. The density of the cell nucleus, The average chord length of the sensitive volume.

5. The method according to claim 4, characterized in that, Also includes: For the cell cluster model used to simulate micro-dose of alpha radionuclides, the simulated cell consists of three concentric spheres with different radii, which are respectively divided into the nucleus, cytoplasm and cell membrane; The simulated cells in the cell cluster model are uniformly arranged in three-dimensional space.

6. The method according to claim 5, characterized in that, In the micro-dose Monte Carlo simulation, there are four possible decay locations for the alpha radionuclide: uniform distribution within the cell, uniform distribution in the cytoplasm, uniform distribution in the intercellular spaces, and uniform distribution throughout the entire cell cluster model.

7. An evaluation apparatus based on the method according to any one of claims 1-6, characterized in that, include: The physical dose simulation module is used to integrate the time-activity curve of alpha radionuclides in organs to obtain the cumulative activity, and to calculate the physical absorbed dose and dose rate of organs through Monte Carlo simulation. The microdose spectrum generation module is used to construct the microdose spectrum of alpha radionuclides based on microdose Monte Carlo simulation, and obtain the saturated corrected dose average linear energy used to characterize radiation quality. The biological effect parameter fitting module is used to obtain the biological effect parameters of the α-radioactive nuclide by fitting the saturated corrected dose mean line energy with cell experimental data using a micro-dose kinetic model. A bioeffective dose calculation module is used to evaluate the bioeffective dose of a target organ by combining the physical absorbed dose, the dose rate, and the biological effect parameters.

8. An electronic device, characterized in that, include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the method as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1-6.

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