Dose evaluation method, irradiation condition selection method, and treatment plan generation device

Abstract

The invention relates to a dose evaluation method, an irradiation condition selection method and a treatment plan generation device. The dose evaluation method comprises the following steps: acquiring tissue material information; determining conjugate flux corresponding to the tissue material according to the tissue material information; and based on the irradiation condition, combining with the conjugate flux corresponding to the tissue material to obtain the radiation absorbed dose corresponding to the tissue material under the irradiation condition. By adopting the method, the radiation absorbed dose corresponding to the tissue material can be quickly calculated, the dose calculation efficiency under a plurality of irradiation conditions is improved, and the radiation absorbed dose corresponding to each tissue material under different irradiation conditions can be quickly evaluated, so that a proper irradiation condition can be quickly selected from the plurality of irradiation conditions conveniently; therefore, the making time of the treatment plan is greatly shortened.

Description

Technical Field

[0001] The present application relates to the field of radiotherapy technology, and in particular to a dose assessment method, an irradiation condition selection method, and a treatment plan generation device. Background Art

[0002] Radiotherapy is a medical method of treating cancer by using radiation to deposit energy around cancer cells to kill them. Depending on the type of radiation, radiotherapy can be divided into photon radiotherapy, electron radiotherapy, proton and heavy ion radiotherapy, and boron neutron capture therapy.

[0003] In order to allow the radiation particles to kill as many cancer cells as possible while reducing damage to normal cells, a computed tomography (CT) or positron emission computed tomography (PET) image scan is usually performed before treating the patient. The tissue material information of the body to be irradiated is obtained based on the scan results. A calculation model is established based on the tissue material information and the radiation source to simulate the transport process of the radiation particles in the body to be irradiated. Finally, the dose distribution of the radiation particles in the body to be irradiated is obtained, and then the treatment plan with the optimal dose distribution for the patient is selected as the patient's treatment plan.

[0004] In the process of generating the above treatment plan, calculating the dose distribution of the patient's irradiated part plays a decisive role in the effect of radiotherapy. Dose distribution calculation is usually carried out under given irradiation conditions, and the selection of irradiation conditions is often based on the physicist's own experience, which has great uncertainty. In traditional technology, dose distribution is mainly obtained by simulating the movement process of radiation particles using the Monte Carlo method. By simulating the transport process of radiation particles in the irradiated body under different irradiation conditions, the dose distribution of patients under different irradiation conditions is obtained. For traditional radiotherapy, it is necessary to simulate the movement process of photons and electrons, and for other radiation irradiation treatments, it is necessary to simulate the movement process of neutrons and photons.

[0005] However, the simulation and calculation process of the above method is time-consuming and memory-intensive. There are many pre-given irradiation conditions. It takes a long time to simulate and calculate each given irradiation condition one by one using the above method. Therefore, it is difficult to select appropriate irradiation conditions within a reasonable calculation time, which is not conducive to the optimization calculation of the treatment plan. Summary of the invention

[0006] Based on this, it is necessary to provide a dose assessment method, an irradiation condition selection method and a treatment plan generation device that can quickly assess the dose and quickly select appropriate irradiation conditions in response to the above technical problems.

[0007] In a first aspect, the present application provides a method for assessing radiation therapy dose, the method comprising:

[0008] Obtain information about organizational materials;

[0009] Determining the conjugate flux corresponding to the tissue material according to the tissue material information;

[0010] Based on the irradiation conditions and combined with the conjugate flux corresponding to the tissue material, the radiation absorbed dose corresponding to the tissue material under the irradiation conditions is obtained.

[0011] In one embodiment, determining the conjugate flux corresponding to the tissue material according to the tissue material information includes:

[0012] Determine the flux dose conversion factor corresponding to the tissue material according to the element information of the tissue material in the tissue material information;

[0013] The conjugate flux corresponding to the tissue material is determined according to the flux dose conversion factor corresponding to the tissue material.

[0014] In one embodiment, the element information includes element composition and element ratio, and the flux dose conversion factor corresponding to the tissue material is determined according to the element information of the tissue material in the tissue material information, including:

[0015] Obtain the density of each nuclide in the tissue material based on the element composition and element proportion;

[0016] Obtain the flux dose conversion factor corresponding to each nuclide;

[0017] The flux dose conversion factor corresponding to each nuclide and the density of each nuclide are combined to determine the flux dose conversion factor corresponding to the tissue material.

[0018] In one embodiment, the flux dose conversion factor corresponding to each nuclide and the density of each nuclide are combined to determine the flux dose conversion factor corresponding to the tissue material, using the following formula:

[0019] Kerma=∑ρ i ·erma i ;

[0020] Among them, ρ i represents the density of the ith nuclide, Kerma i Represents the flux dose conversion factor corresponding to the i-th nuclide.

[0021] In one embodiment, the conjugate flux corresponding to the tissue material is determined according to the flux dose conversion factor corresponding to the tissue material, using the following formula:

[0022]

[0023] in, represents the conjugate flux, P1 and P2 represent different particle state parameters, represents the conjugate flux of the particle in the P1 state, Kerma represents the flux dose conversion factor, K * represents the conjugate nucleus, K * (2→P1) represents the probability that a particle reaches the P2 state from the P1 state through collision reaction.

[0024] In one embodiment, based on the irradiation conditions and in combination with the conjugate flux corresponding to the tissue material, obtaining the radiation absorbed dose corresponding to the tissue material under the irradiation conditions includes:

[0025] Based on the irradiation condition, determining the source term distribution corresponding to the irradiation condition, wherein the source term distribution is used to characterize the distribution function of the particle source under the irradiation condition;

[0026] The radiation absorbed dose corresponding to the tissue material is obtained according to the source term distribution and the conjugate flux corresponding to the tissue material.

[0027] In a second aspect, the present application also provides a method for selecting irradiation conditions, the method comprising:

[0028] Combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the radiation absorbed dose corresponding to each tissue material is obtained;

[0029] At least one suitable irradiation condition is selected according to the radiation absorption dose corresponding to each tissue material.

[0030] In one embodiment, at least one suitable irradiation condition is selected according to the radiation absorption dose corresponding to each tissue material, including:

[0031] If the radiation absorption doses corresponding to the various tissue materials meet the preset conditions, the irradiation conditions are accepted.

[0032] In one embodiment, the tissue material includes at least tumor tissue material and important organ tissue material. If the radiation absorption dose corresponding to each tissue material meets the preset conditions, the irradiation condition is accepted, including:

[0033] If the radiation absorption dose corresponding to the tumor tissue material is greater than the first preset threshold, and the radiation absorption dose corresponding to the important organ tissue material is less than the second preset threshold, the irradiation condition is accepted.

[0034] In one embodiment, before obtaining the radiation absorption dose corresponding to each tissue material by combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the method includes:

[0035] Based on at least one preset region of interest, tissue material corresponding to the region of interest is determined.

[0036] In one embodiment, before obtaining the radiation absorption dose corresponding to each tissue material by combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the method includes:

[0037] Based on at least one preset region of interest and in combination with the concentration distribution of the targeting element in the region of interest, the tissue material corresponding to the region of interest is determined.

[0038] In one embodiment, according to the radiation absorption dose corresponding to each tissue material, appropriate irradiation conditions are selected, including:

[0039] Determine the radiation absorbed dose of the region of interest according to the radiation absorbed doses corresponding to all tissue materials in the region of interest;

[0040] Select appropriate irradiation conditions based on the radiation absorbed dose of the area of ​​interest.

[0041] In a third aspect, the present application also provides a method for generating a treatment plan, the method comprising:

[0042] Combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the radiation absorbed dose corresponding to each tissue material is obtained;

[0043] Selecting at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material;

[0044] Generate a treatment plan based on appropriate irradiation conditions.

[0045] In one embodiment, at least one suitable irradiation condition is selected according to the radiation absorption dose corresponding to each tissue material, including:

[0046] If the radiation absorption doses corresponding to the various tissue materials meet the preset conditions, the irradiation conditions are accepted.

[0047] In one embodiment, the tissue material includes at least tumor tissue material and important organ tissue material. If the radiation absorption dose corresponding to each tissue material meets the preset conditions, the irradiation condition is accepted, including:

[0048] If the radiation absorption dose corresponding to the tumor tissue material is greater than the first preset threshold, and the radiation absorption dose corresponding to the important organ tissue material is less than the second preset threshold, the irradiation condition is accepted.

[0049] In one embodiment, before obtaining the radiation absorption dose corresponding to each tissue material by combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the method includes:

[0050] Based on at least one preset region of interest, tissue material corresponding to the region of interest is determined.

[0051] In one embodiment, before obtaining the radiation absorption dose corresponding to each tissue material by combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the method includes:

[0052] Based on at least one preset region of interest and in combination with the concentration distribution of the targeting element in the region of interest, the tissue material corresponding to the region of interest is determined.

[0053] In one embodiment, according to the radiation absorption dose corresponding to each tissue material, appropriate irradiation conditions are selected, including:

[0054] Determine the radiation absorbed dose of the region of interest according to the radiation absorbed doses corresponding to all tissue materials in the region of interest;

[0055] Select appropriate irradiation conditions based on the radiation absorbed dose of the area of ​​interest.

[0056] In one embodiment, generating a treatment plan according to appropriate irradiation conditions includes:

[0057] The corresponding flux is determined according to appropriate irradiation conditions, and the dose distribution is calculated based on the flux using a Monte Carlo simulation program.

[0058] In a fourth aspect, the present application further provides a treatment plan generating device, the device comprising:

[0059] A radiation source module is used to establish source term information according to different irradiation conditions;

[0060] A medical imaging data module, used to obtain tissue material information based on medical imaging data and establish a three-dimensional voxel tissue model;

[0061] The dose assessment module is used to determine the conjugate flux corresponding to the tissue material according to the tissue material information, and to obtain the radiation absorption dose corresponding to each tissue material by combining the source term information and the conjugate flux corresponding to the tissue material;

[0062] An irradiation condition selection module is used to select at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material;

[0063] The treatment plan generation module is used to generate a treatment plan based on appropriate irradiation conditions.

[0064] In a fifth aspect, the present application also provides a radiotherapy system, the system comprising:

[0065] A beam generating device for generating a therapeutic beam;

[0066] A beam adjustment device, used for adjusting the therapeutic beam generated by the beam generating device;

[0067] A treatment plan generating device is used to establish source term information according to different irradiation conditions, obtain tissue material information based on medical image data, establish a three-dimensional voxel tissue model, determine the conjugate flux corresponding to the tissue material according to the tissue material information, combine the source term information and the conjugate flux corresponding to the tissue material to obtain the radiation absorption dose corresponding to each tissue material, select at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material, and generate a treatment plan according to the suitable irradiation condition;

[0068] The beam control device is used to retrieve the corresponding treatment plan from the treatment plan generating device and control the beam generating device to execute the treatment plan.

[0069] In a sixth aspect, the present application also provides a radiotherapy system, the system comprising a memory and a processor;

[0070] Memory for storing computer programs;

[0071] A processor is used to implement the radiotherapy dose assessment method provided in the first aspect of the present application, the irradiation condition selection method provided in the second aspect of the present application, or the treatment plan generation method provided in the third aspect of the present application when executing a computer program.

[0072] In the seventh aspect, the present application also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the radiotherapy dose assessment method provided in the first aspect of the present application, the irradiation condition selection method provided in the second aspect of the present application, or the treatment plan generation method provided in the third aspect of the present application.

[0073] The above-mentioned radiotherapy dose assessment method obtains tissue material information, determines the conjugate flux corresponding to the tissue material according to the tissue material information, and obtains the radiation absorption dose corresponding to the tissue material under the irradiation conditions based on the irradiation conditions and the conjugate flux corresponding to the tissue material. Since the assessment of the radiation absorption dose by combining the irradiation conditions and the conjugate flux is relatively simple, the above-mentioned method can quickly assess the radiation absorption dose corresponding to the tissue material.

[0074] Furthermore, since the conjugate flux is independent of the source term S, the number of calculations is only related to the counting target of the tissue material to be considered. No matter how the irradiation conditions change, the conjugate flux corresponding to the tissue material is determined, and the radiation absorption dose corresponding to the tissue material under multiple different irradiation conditions can be quickly obtained, and the radiation absorption dose of each region of interest under multiple different irradiation conditions can also be quickly obtained. Therefore, in the above-mentioned irradiation condition selection method, when it is necessary to select at least one suitable irradiation condition from multiple different irradiation conditions, it is only necessary to calculate the conjugate flux several times to evaluate the radiation absorption dose of each tissue material or each region of interest under multiple different irradiation conditions, and the appropriate irradiation condition can be quickly selected based on the radiation absorption dose under multiple different irradiation conditions.

[0075] Furthermore, in the above treatment plan generation method, since a suitable irradiation condition can be quickly selected from a plurality of different irradiation conditions, the time for formulating the treatment plan is greatly shortened. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 is an application environment diagram in one embodiment;

[0077] Figure 2 is a schematic flow chart of a method for assessing radiation therapy dose in one embodiment;

[0078] Figure 3 A schematic flow chart of a method for selecting irradiation conditions in one embodiment;

[0079] Figure 4 is a flow chart of a method for generating a treatment plan in one embodiment;

[0080] Figure 5 is a structural block diagram of a treatment plan generating device in one embodiment;

[0081] Figure 6 is a structural block diagram of a radiotherapy system in one embodiment;

[0082] Figure 7 FIG. 4 is a structural block diagram of a radiotherapy system in another embodiment. DETAILED DESCRIPTION

[0083] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0084] The radiation therapy dose assessment method, irradiation condition selection method, and treatment plan generation method provided in the embodiments of the present application can be applied to Figure 1In the application environment shown. Among them, the terminal 102 communicates with the server 104 through the network, and the data storage system can store the data that the server 104 needs to process. The data storage system can be integrated on the server 104, or it can be placed on the cloud or other network servers. Among them, the terminal 102 can be, but is not limited to, various personal computers, laptops, smart phones, tablet computers, Internet of Things devices and portable wearable devices. The Internet of Things devices can be smart speakers, smart TVs, smart air conditioners, smart car-mounted devices, etc. Portable wearable devices can be smart watches, smart bracelets, head-mounted devices, etc. The server 104 can be implemented with an independent server or a server cluster consisting of multiple servers.

[0085] It should be noted that the radiation therapy dose assessment method, irradiation condition selection method, and treatment plan generation method provided in the embodiment of the present application can generally be executed by the server 104. Accordingly, the treatment plan generation device provided in the embodiment of the present application can generally be set in the server 104. The radiation therapy dose assessment method, irradiation condition selection method, and treatment plan generation method provided in the embodiment of the present application can also be executed by a server or server cluster that is different from the server 104 and can communicate with the terminal 102 device or the server 104. Accordingly, the treatment plan generation device provided in the embodiment of the present application can also be set in a server or server cluster that is different from the server 104 and can communicate with the terminal 102 device or the server 104 for execution.

[0086] It should be understood that Figure 1 The number of terminal devices, networks and servers in the embodiment is only for illustration. Any number of terminal devices, networks and servers may be provided according to implementation requirements.

[0087] The basic physical principle of radiotherapy technology is to irradiate tumor tissue with radiation, and through the interaction between radiation and tumor tissue, the energy carried by the radiation is deposited into the cancer cells to kill them. Its fundamental goal is to kill as many cancer cells as possible (giving the tumor tissue the highest possible radiation absorption dose) while protecting healthy tissue (giving the healthy tissue the lowest possible radiation absorption dose).

[0088] The radiation therapy dose assessment method, irradiation condition selection method and treatment plan generation method provided in the embodiments of the present application can be used for radiation therapy that uses radiation for treatment, such as: traditional radiotherapy, proton radiotherapy, X-ray radiotherapy, electron beam radiotherapy, neutron capture therapy and boron neutron capture therapy.

[0089] In radiotherapy technology, the Monte Carlo method can accurately simulate the collision trajectory and energy distribution of nuclear particles in the three-dimensional space inside the irradiated body. During the simulation process, in order to determine the radiation absorption dose distribution of the irradiated body under certain irradiation conditions, the traditional method uses computer technology to process medical imaging data and establish an accurate grid model required by the Monte Carlo software, and then combines the Monte Carlo software to perform dose simulation calculations. In the Monte Carlo dose calculation program, the dose D is calculated using the following formula 1:

[0090]

[0091] Where D is the dose, is the flux, kerma is the flux dose conversion factor, and P is the parameter characterizing the particle state, where the parameters of the particle state include spatial position r, angle Ω, and energy E.

[0092] Flux Calculate using formula 2:

[0093]

[0094] Among them, P1 and P2 represent different particle state parameters, S represents the source term, S(P1) represents the number of particles in the P1 state under the initial source state, K is the transport nuclear parameter in the nuclear reaction database, and K(P2→P1) represents the collision probability of particles reaching the P1 state from the P2 state.

[0095] According to formula 2, the flux of particles in the P1 state is It consists of two parts. The first part is the number of particles in the P1 state under the initial source state, and the second part is the number of particles in other states (different from the P1 state) that reach the P1 state through collision reactions. Formula 2 integrates all P2s, that is, it summarizes the number of particles in all states different from the P1 state that are converted into P1.

[0096] In the above-mentioned dose simulation calculation using the Monte Carlo method, the flux The calculation of is a relatively complex and time-consuming process, resulting in low efficiency of dose calculation. In addition, in radiotherapy technology, it is often necessary to calculate a large number of dose distributions of tissue materials under different irradiation conditions, so as to select appropriate irradiation conditions based on the dose distributions of tissue materials under different irradiation conditions. Different irradiation conditions are essentially different source terms S. Combining the above formulas 1 and 2, it can be seen that the flux It is related to the source term S, that is, it is related to the irradiation conditions. When calculating the dose D of tissue materials under different irradiation conditions, for each irradiation condition, the flux corresponding to the irradiation condition must be calculated. The flux The calculation is complex and time-consuming, so the flux When calculating the dose, it often takes a lot of time to calculate the dose distribution of tissue materials under various irradiation conditions, making it difficult to select appropriate irradiation conditions in a short time.

[0097] Based on this, in order to be able to quickly evaluate the radiation absorption dose of tissue materials, and to quickly evaluate the radiation absorption dose of tissue materials under different irradiation conditions, so as to facilitate and quickly find suitable irradiation conditions, an embodiment of the present application provides a method for evaluating radiation therapy dose. In one embodiment, Figure 2 As shown, the following steps are included:

[0098] Get information about tissue materials:

[0099] Among them, tissue material information includes element information of tissue materials, such as the element composition and element proportion of tissue materials. Human tissue contains more than 60 elements, of which more than 20 are essential elements, which are of great significance to maintaining the normal physiological functions of the body. The elements with higher content include carbon, hydrogen, oxygen, nitrogen, sodium, phosphorus, sodium, magnesium, potassium, calcium and other elements. In addition, there is a small amount of iron in blood tissue and a small amount of iodine in thyroid tissue.

[0100] In addition, in some radiotherapy techniques, before the controlled therapeutic beam is used to irradiate the body to be irradiated, targeted molecular drugs are injected into the body to be irradiated, so as to utilize the selectivity of targeted molecular drugs to make the targeted elements specifically accumulate in certain tissues. For example, in boron neutron capture therapy, boron ( 10 B) Drugs selectively accumulate in tumor tissues, using boron ( 10 B) It has the characteristic of high capture cross section for thermal neutrons, so as to achieve the purpose of locally killing tumor cells. In this application scenario, the element composition of the tissue material may also include the targeted element, and the element proportion of the tissue material may also include the proportion of the targeted element.

[0101] In radiotherapy technology, medical images such as Magnetic Resonance Imaging (MRI) or Computed Tomography (CT) can provide more detailed tissue geometry information for the internal features of the body to be irradiated. Taking computed tomography as an example, tissue materials can be defined according to CT values, also known as HU values ​​(Hounsfield Unit). HU values ​​in a fixed range correspond to tissue materials with a fixed element composition ratio. For example, HU values ​​between -100 and 20 can correspond to fat tissue with a fixed element composition ratio, HU values ​​between 20 and 100 can correspond to muscle tissue with a fixed element composition ratio, and HU values ​​between -951 and 120 can correspond to lung tissue with a fixed element composition ratio.

[0102] When the embodiments of the present application realize the conversion between medical imaging data and tissue materials and tissue material information, there may be some tissue materials covering a wide range of HU values, resulting in lower accuracy of dose calculation. In this case, the tissue materials covering a wide range of HU values ​​can be further divided, for example, lung tissue can be divided into low-density lung tissue and high-density lung tissue.

[0103] For radiotherapy techniques including targeted elements, the embodiments of the present application may assume that the concentration distribution of the targeted elements in part or all of the tissue materials is non-uniform, and obtain non-uniform targeted element distribution information through medical images such as positron emission computed tomography (PET), thereby further dividing part or all of the tissue materials according to the targeted element distribution information, for example, further dividing the tumor tissue material into multiple tissue materials based on the boron concentration, so as to more accurately evaluate the radiation absorption dose of tumor tissue materials with different boron concentrations.

[0104] In the embodiments of the present application, different tissue materials need to be considered or calculated for dose for tumors in different locations. For head and neck cancer, the tissue materials that need to be considered usually include skin, brain, brainstem, eye, mucosa, mandible, spinal cord, and tumor, etc. In the embodiments of the present application, the geometric space of the tissue materials that need to be considered can be delineated based on the medical images of the body to be irradiated.

[0105] It should be noted that acquiring tissue material information in the embodiment of the present application specifically refers to acquiring information of target tissue materials for subsequent dose assessment.

[0106] It should be noted that the embodiment of the present application does not specifically limit the definition of tissue materials, that is, the conversion relationship between medical imaging data and tissue materials. The tissue materials that require dose assessment can be defined based on the accuracy requirements of the actual dose assessment and the tumor location.

[0107] It should be noted that the embodiments of the present application do not specifically limit the method for obtaining tissue material information. For example, in proton radiotherapy, the HU value can be converted into the corresponding tissue material according to a specific relationship through the TOPAS software, and the tissue material element information defined by default in the TOPAS software can be obtained; for example, in boron neutron capture therapy, the material template library of the MCNP software and PET medical imaging data or blood boron concentration can be combined to obtain tissue material information.

[0108] According to the tissue material information, determine the conjugate flux corresponding to the tissue material:

[0109] The conjugate flux corresponding to the tissue material includes distribution information of the conjugate flux in the geometric space of the tissue material.

[0110] Exemplarily, after obtaining the tissue material information, the conjugate flux corresponding to the tissue material is determined according to the element information in the tissue material information, wherein the conjugate flux has no relationship with the variable source term S, i.e., the parameter of the radiation. Therefore, when the radiation therapy dose assessment method provided in the embodiment of the present application is used to calculate the dose distribution under multiple irradiation conditions, the conjugate flux corresponding to one tissue material only needs to be calculated once, i.e., the number of calculations of the conjugate flux is only related to the number of tissue material types that need to be considered, and has nothing to do with the number of irradiation conditions.

[0111] Based on the irradiation conditions and the conjugate flux corresponding to the tissue material, the radiation absorbed dose corresponding to the tissue material under the irradiation conditions is obtained:

[0112] Among them, the irradiation conditions include the irradiation direction, irradiation position and beam parameters of the radioactive particles to form a beam. Different irradiation conditions are essentially different source terms S. Under different irradiation conditions, different radioactive particles have different distribution states. The source term S can be expressed by the distribution function of the particles.

[0113] Exemplarily, after determining the conjugate flux corresponding to the tissue material, based on the irradiation conditions and in combination with the conjugate flux corresponding to the tissue material, the radiation absorption dose corresponding to the tissue material under the irradiation conditions can be determined. For example, based on the conjugate flux corresponding to the tumor tissue and the given irradiation conditions, the radiation absorption dose corresponding to the tumor tissue under the irradiation conditions can be obtained.

[0114] In radiotherapy technology, it is often necessary to calculate the dose distribution of tissue materials under different irradiation conditions. For example, in order to select the appropriate irradiation condition from 100 irradiation conditions, it is necessary to calculate the dose D of the radioactive particles corresponding to the 100 irradiation conditions. When calculating the dose D, the flux Formula 2 is used for calculation. According to formula 2, the flux can be known Related to the source term S, it is equivalent to calculating the flux for each irradiation condition Then you need to calculate the flux 100 times Only then can the dose D corresponding to 100 irradiation conditions be obtained; and when the conjugate flux provided in the embodiment of the present application is used to calculate the dose D, since the conjugate flux is not associated with the source term S, the number of calculations is only related to the counting target of the type of tissue material to be considered. Therefore, for different irradiation conditions, the conjugate flux corresponding to the tissue material is the same, and the conjugate flux provided in the embodiment of the present application is used to calculate the dose D. It is only necessary to calculate the conjugate flux several times, and then combine the 100 irradiation conditions to calculate the dose D corresponding to the tissue material under each irradiation condition, where the specific number depends on the number of tissue material types to be considered, generally the number of tumor tissues and normal tissues, and the number of tissue materials is obviously much smaller than the number of irradiation conditions to be considered. And the calculated flux is a very complicated process, and the calculation of conjugate flux is much more complicated than the calculation of flux. The calculation of the dose D under multiple irradiation conditions is relatively simple, and the calculation of the dose D under the combination of irradiation conditions and conjugate flux is also relatively simple. Therefore, the calculation of the dose D under multiple irradiation conditions using conjugate flux is more convenient than using flux. Calculation of the dose D for multiple irradiation conditions is significantly faster.

[0115] In the above-mentioned radiotherapy dose assessment method, tissue material information is first obtained, and the conjugate flux corresponding to the tissue material is determined according to the tissue material information. Based on the irradiation conditions, the conjugate flux corresponding to the tissue material is combined to obtain the radiation absorption dose corresponding to the tissue material under the irradiation conditions. Since the calculation of the conjugate flux is relatively simple, the calculation of the radiation absorption dose in combination with the irradiation conditions and the conjugate flux is also relatively simple. Therefore, the above-mentioned method can quickly assess the radiation absorption dose corresponding to the tissue material. Moreover, when the above-mentioned method is used to assess the dose distribution under multiple irradiation conditions, since the conjugate flux is independent of the source term S, the number of calculations is only related to the counting target of the tissue material to be considered. Therefore, no matter how the irradiation conditions change, the conjugate flux corresponding to the tissue material is determined. Then, the above-mentioned radiotherapy dose assessment method only needs to calculate the conjugate flux several times to assess the dose distribution under multiple irradiation conditions, thereby improving the efficiency of dose assessment under multiple irradiation conditions.

[0116] In one embodiment, determining the conjugate flux corresponding to the tissue material according to the tissue material information comprises the following steps:

[0117] According to the element information of the tissue material in the tissue material information, the flux dose conversion factor corresponding to the tissue material is determined:

[0118] Among them, the flux dose conversion factor (Kerma) of a certain tissue material is determined by the elemental composition and element proportion of the tissue material. According to the particle energy, the flux dose conversion factor of each nuclide at the corresponding energy can be found in the cross-section database.

[0119] In one implementation, first, the density of each nuclide in the tissue material is obtained based on the elemental composition and element proportion in the tissue material, and the flux dose conversion factor corresponding to each nuclide is obtained. The flux dose conversion factor corresponding to each nuclide and the density of each nuclide are combined to determine the flux dose conversion factor corresponding to the tissue material.

[0120] In one implementation, the flux dose conversion factor corresponding to each nuclide and the density of each nuclide are combined to determine the flux dose conversion factor corresponding to the tissue material, using the following formula:

[0121] Kerma=∑ρ i ·erma i ; (Formula 3)

[0122] Among them, ρ i represents the density of the ith nuclide, Kerma i Represents the flux dose conversion factor corresponding to the i-th nuclide.

[0123] According to the flux dose conversion factor corresponding to the tissue material, the conjugate flux corresponding to the tissue material is determined:

[0124] In one implementation, according to the flux dose conversion factor Kerma corresponding to the tissue material, combined with the above formula 2, the flux dose conversion factor Kerma corresponding to the tissue material is used as the source term to construct a conjugate equation, and the conjugate flux corresponding to the tissue material is determined by using the conjugate equation. The conjugate equation is as follows:

[0125]

[0126] in, represents the conjugate flux, P1 and P2 represent different particle state parameters, represents the conjugate flux of the particle in the P1 state, Kerma represents the flux dose conversion factor, K * Represents the conjugate nuclear parameters from the Nuclear Reaction Database.

[0127] Among them, the transport core K and the conjugated core K* The following relations are satisfied:

[0128] K(P2→P1)= * (1→P2); (Formula 5)

[0129] It can be seen that K in the above formula 4 * (2→P1) is equal to K(P1→P2), which is the probability that a particle reaches the P2 state through collision reaction from the P1 state.

[0130] In this embodiment, the flux dose conversion factor corresponding to the tissue material is determined by the element information of the tissue material in the tissue material information, and the conjugate flux corresponding to the tissue material is determined according to the flux dose conversion factor corresponding to the tissue material. Referring to Formula 4, the conjugate flux is independent of the source term S, and is related to the flux dose conversion factor Kerma, and the flux dose conversion factor Kerma corresponds to the tissue material. The density of nuclides in different tissue materials is different, and different nuclides correspond to different Kerma values. By combining the density of each nuclide of the tissue material and the Kerma value corresponding to each nuclide, the Kerma value corresponding to the tissue material can be obtained, and then according to Formula 4, the conjugate flux corresponding to the tissue material is determined by the Kerma value corresponding to the tissue material.

[0131] In one embodiment, based on the irradiation conditions and in combination with the conjugate flux corresponding to the tissue material, the radiation absorption dose corresponding to the tissue material under the irradiation conditions is obtained, including:

[0132] Based on the irradiation conditions, the source term distribution corresponding to the irradiation conditions is determined:

[0133] Among them, the source term distribution is the source term S, which is used to characterize the distribution function of the particle source under irradiation conditions.

[0134] According to the source term distribution and the conjugate flux corresponding to the tissue material, the radiation absorbed dose corresponding to the tissue material is obtained:

[0135] Please combine Formula 2 and Formula 4 and add both sides of the equal sign of Formula 2 to To do the inner product, add both sides of the equation Doing the inner product gives:

[0136]

[0137]

[0138] According to Formula 5, the two double integrals on the right side of the equal sign in Formula 6 and Formula 7 are equal. Eliminating the equal parts yields:

[0139]

[0140] Combining Formula 1, Formula 2, Formula 4 and Formula 8, we can get:

[0141]

[0142] Formula 9 shows that the dose can be expressed by the flux The inner product with the flux-dose conversion factor Kerma can also be obtained by conjugating the flux The inner product with the source term S gives us .

[0143] In this embodiment, the source term distribution function corresponding to the irradiation condition is determined by the irradiation condition, and then the radiation absorption dose corresponding to the region of interest is obtained by taking the inner product of the source term distribution function and the conjugate flux corresponding to the tissue material. is a complex and time-consuming process, and conjugate flux The calculation of the flux The calculation of is relatively simple, and the calculation of the inner product is also relatively simple. Therefore, the above method can quickly evaluate the radiation absorption dose corresponding to the tissue material, and when evaluating the dose distribution under multiple irradiation conditions, for example, in order to select a suitable irradiation condition from 100 irradiation conditions, the conjugate flux provided in the embodiment of the present application is used. To calculate the dose D, we only need to calculate the conjugate flux several times The specific number depends on the counting target of the tissue material to be considered, and then the conjugate flux The dose D corresponding to different source terms can be obtained by performing 100 inner products with the source term distribution function, which can greatly save the dose assessment time and improve the efficiency of dose assessment.

[0144] Based on the same inventive concept, the embodiment of the present application also provides an irradiation condition selection method. The implementation solution provided by the irradiation condition selection method is similar to the implementation solution recorded in the above-mentioned radiotherapy dose assessment method, so the specific limitations in one or more irradiation condition selection method embodiments provided below can refer to the limitations of the radiotherapy dose assessment method embodiments above, and will not be repeated here.

[0145] In one embodiment, Figure 3 As shown, a method for selecting irradiation conditions is provided, comprising the following steps:

[0146] Combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the radiation absorbed dose corresponding to each tissue material is obtained:

[0147] Among them, when selecting appropriate irradiation conditions, it is required that high doses of radiation be delivered to the tumor target area as much as possible to minimize damage to surrounding organs (healthy tissues). In order to better control the dose distribution in each organ or target area, appropriate irradiation conditions are selected so that the radiation can kill tumor cells while minimizing damage to surrounding normal tissues. The tissue material of the embodiment of the present application may include tumor tissue and at least one important organ tissue in the surrounding area.

[0148] In one implementation, multiple irradiation conditions can be predetermined based on the tumor type, location, and size, based on the experience of the physicist. Sampling from multiple irradiation conditions, i.e., selecting a certain irradiation condition, can be selected randomly or in a pre-set order, and combining the irradiation condition and the conjugate flux corresponding to each tissue material to obtain the radiation absorption dose corresponding to each tissue material under the irradiation condition.

[0149] According to the radiation absorption dose corresponding to each tissue material, select at least one appropriate irradiation condition:

[0150] In one implementation, if the radiation absorption dose corresponding to each tissue material meets the preset conditions, the irradiation conditions are accepted; if the radiation absorption dose corresponding to each tissue material does not meet the preset conditions, the irradiation conditions are resampled and the radiation absorption dose corresponding to each tissue material under the resampled irradiation conditions is evaluated.

[0151] Exemplarily, the tissue material includes tumor tissue material and vital organ tissue material. If the radiation absorption dose corresponding to the tumor tissue material is greater than a first preset threshold, and the radiation absorption dose corresponding to the vital organ tissue material is less than a second preset threshold, the irradiation condition is accepted as a suitable irradiation condition.

[0152] In one implementation, multiple irradiation conditions are optimized according to the radiation absorption dose corresponding to each tissue material, so as to select at least one suitable irradiation condition.

[0153] Exemplarily, for the radiation absorption dose corresponding to each tissue material under each irradiation condition, the irradiation conditions that meet the preset conditions are first screened out, and then the multiple irradiation conditions that meet the preset conditions are sorted and optimized, wherein the optimization can be determined by comparing the radiation absorption dose corresponding to the tumor tissue under each irradiation condition, and comparing the radiation absorption dose corresponding to other important organ tissue materials under each irradiation condition. Different weights can also be assigned to different tissue materials according to actual conditions for optimization. The embodiment of the present application is not specifically limited here.

[0154] It should be noted that it is preferred to select an optimal irradiation condition or multiple optimal irradiation conditions, and use the optimal or multiple optimal irradiation conditions as the appropriate irradiation condition. Alternatively, when multiple optimal irradiation conditions are selected, a Monte Carlo simulation program can be used to calculate more accurate dose distributions under multiple optimal irradiation conditions based on the fluxes corresponding to the multiple optimal irradiation conditions, and then compare them to determine the appropriate irradiation condition.

[0155] In this embodiment, the radiation absorption dose corresponding to each tissue material is obtained by combining the irradiation conditions and the conjugate flux corresponding to the tissue material, and at least one suitable irradiation condition is selected according to the radiation absorption dose corresponding to each tissue material. Since the conjugate flux is independent of the source term S, the number of calculations thereof is only related to the counting target of the tissue material to be considered. Therefore, no matter how the irradiation conditions change, the conjugate flux corresponding to the tissue material is determined. Then, the above irradiation condition selection method only needs to calculate the conjugate flux several times to evaluate the radiation absorption dose of each tissue material under multiple irradiation conditions, thereby improving the efficiency of dose calculation under multiple irradiation conditions, being able to quickly evaluate the radiation absorption dose corresponding to each tissue material under different irradiation conditions, and facilitating the rapid selection of suitable irradiation conditions from multiple irradiation conditions.

[0156] In one embodiment, before obtaining the radiation absorption dose corresponding to each tissue material by combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the method includes: determining the tissue material corresponding to the region of interest based on at least one preset region of interest.

[0157] Among them, the region of interest (ROI) can be the target area for particle deposition, such as the tumor area that needs to be treated. The region of interest can also be a protective area around the target area, such as the area where important organs and tissues are located, which can be key organs such as eyes, liver, etc., or important tissues such as bone tissue, brain tissue, etc.

[0158] The embodiment of the present application can pre-set at least one ROI area that needs to be defined for different tumor types. For example, the ROI types that need to be paid attention to during the treatment of brain tumors may include air, skin, carotid, mucosa, brain tissue, eyeball, lens, gland, skeleton, soft tissue or brain tumor, etc.

[0159] Based on medical imaging data, such as HU values, the corresponding ROI boundaries can be automatically defined, automatically read, or manually defined by the operator. Through the definition of the ROI boundaries, the three-dimensional medical imaging geometric model of the body to be irradiated is divided into corresponding ROI areas, that is, each voxel grid is divided into the corresponding ROI area.

[0160] After at least one ROI region is preset, the embodiment of the present application determines the tissue material corresponding to each ROI region. For example, the HU value range corresponding to each ROI region, one or more tissue material types corresponding to different ROI regions, HU values ​​corresponding to the tissue materials, and element information corresponding to the tissue materials are pre-set in the material template library.

[0161] For example, some ROI regions cover a narrower range of HU values, and one ROI region may correspond to one tissue material.

[0162] For example, some ROI regions cover a wider range of HU values, and the ROI region can be further divided into different tissue material types according to different HU value ranges to obtain multiple tissue materials corresponding to the ROI region.

[0163] It should be noted that in the radiotherapy application scenario including the targeted element, this embodiment assumes that the concentration distribution of the targeted element in the ROI region is a uniform concentration distribution.

[0164] In this embodiment, by selecting at least one preset region of interest, determining the type of tissue material corresponding to the region of interest based on the tissue density in the medical imaging data, and obtaining one or more tissue materials corresponding to the region of interest, the radiation absorption dose of the tissue material can be evaluated more accurately.

[0165] In another embodiment, before obtaining the radiation absorption dose corresponding to each tissue material in combination with the irradiation conditions and the conjugate flux corresponding to the tissue material, it includes: based on at least one preset region of interest, combined with the concentration distribution of the targeting element in the region of interest, determining the tissue material corresponding to the region of interest.

[0166] This embodiment is applied to a radiotherapy scenario including a targeted element. In this embodiment, the concentration distribution of the targeted element in the ROI region is assumed to be a partially non-uniform or completely non-uniform concentration distribution.

[0167] Exemplarily, after the ROI area is preset, the initial tissue material type of the ROI area can be first determined based on the HU value of the ROI area, and then based on the non-uniform concentration distribution information of the targeted element, some or all of the tissue materials in the initial tissue material type can be further divided. For example, in boron neutron capture therapy, a certain ROI area is delineated according to the HU value to correspond to a tissue material, and the tissue material is tumor tissue. Furthermore, the non-uniform boron nuclide concentration distribution information in the ROI area can be obtained through medical imaging such as PET, and based on the non-uniform boron nuclide concentration distribution information, the ROI area can be further divided into tumor 1 tissue material, tumor 2 tissue material, tumor 3 tissue material, etc.

[0168] In this embodiment, the tissue material corresponding to the region of interest is determined by combining the concentration distribution of the targeting element in the region of interest. Since the targeting element also has a corresponding flux dose conversion factor Kerma value in the calculation of the radiation absorbed dose of the tissue material, the non-uniform distribution of the targeting element may affect the flux dose conversion factor Kerma value corresponding to the tissue material, thereby causing a deviation in the radiation absorbed dose of the tissue material. Therefore, in this embodiment, the tissue material in the region of interest can be further divided according to the concentration distribution of the targeting element, so as to more accurately evaluate the radiation absorbed dose of the tissue material.

[0169] In one embodiment, according to the radiation absorption dose corresponding to each tissue material, appropriate irradiation conditions are selected, including:

[0170] Determine the radiation absorbed dose of the region of interest based on the radiation absorbed dose corresponding to all tissue materials in the region of interest:

[0171] Before obtaining the radiation absorbed dose corresponding to each tissue material, when a region of interest is selected, appropriate irradiation conditions can be selected according to the total radiation absorbed dose in the region of interest.

[0172] Exemplarily, when there is only one type of tissue material in the region of interest, the total radiation absorbed dose in the region of interest is the absorbed dose of the tissue material corresponding to the region of interest.

[0173] For example, when the region of interest includes multiple tissue materials, the total deposition energy of all tissue materials can be divided by the region mass of the region of interest to obtain the radiation absorbed dose of the region of interest, that is, the total average dose of the region of interest is used as the radiation absorbed dose of the region of interest. The radiation absorbed dose of the region of interest can be expressed as follows:

[0174]

[0175] Among them, E i_depositerepresents the total deposited energy corresponding to the i-th tissue material, M i represents the mass of the i-th tissue material, D i Represents the radiation absorbed dose corresponding to the i-th tissue material.

[0176] Select appropriate irradiation conditions based on the radiation absorbed dose of the area of ​​interest.

[0177] In this embodiment, after selecting a region of interest and dividing the tissue material within the region of interest, the radiation absorption dose corresponding to the tissue material is determined by the conjugate flux and the irradiation conditions. The radiation absorption dose of the region of interest is determined by the radiation absorption dose corresponding to all tissue materials within the region of interest and the mass of all tissue materials. The appropriate irradiation conditions are selected by judging whether the radiation absorption dose of the region of interest meets the preset conditions.

[0178] Based on the same inventive concept, an embodiment of the present application also provides a treatment plan generation method, which adopts the above-mentioned irradiation condition selection method to realize the generation of a treatment plan, combines the irradiation conditions and the conjugate flux corresponding to the tissue material, obtains the radiation absorption dose corresponding to each tissue material, selects at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material, and generates a treatment plan according to the suitable irradiation condition.

[0179] Among them, the radiation absorption dose corresponding to each tissue material is obtained by combining the irradiation conditions and the conjugate flux corresponding to the tissue material. The step of selecting at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material is the same as the implementation scheme recorded in the above-mentioned irradiation condition selection method. Therefore, the specific limitations in one or more treatment plan generation method embodiments provided below can refer to the limitations on the irradiation condition selection method above, and will not be repeated here.

[0180] In one embodiment, Figure 4 As shown, the treatment plan generation method includes: combining the irradiation conditions and the conjugate flux corresponding to the tissue material to obtain the radiation absorption dose corresponding to each tissue material; selecting at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material; and generating a treatment plan according to the suitable irradiation condition.

[0181] In one embodiment, at least one suitable irradiation condition is selected according to the radiation absorption dose corresponding to each tissue material, including: if the radiation absorption dose corresponding to each tissue material satisfies a preset condition, the irradiation condition is accepted.

[0182] In one embodiment, the tissue material includes tumor tissue material and important organ tissue material. If the radiation absorption dose corresponding to each tissue material meets the preset conditions, the irradiation condition is accepted, including: if the radiation absorption dose corresponding to the tumor tissue material is greater than a first preset threshold, and the radiation absorption dose corresponding to the important organ tissue material is less than a second preset threshold, the irradiation condition is accepted.

[0183] In one embodiment, before obtaining the radiation absorption dose corresponding to each tissue material by combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the method includes: determining the tissue material corresponding to the region of interest based on at least one preset region of interest.

[0184] In one embodiment, before obtaining the radiation absorption dose corresponding to each tissue material by combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the method includes: determining the tissue material corresponding to the region of interest based on at least one preset region of interest and the concentration distribution of the targeting element in the region of interest.

[0185] In one embodiment, appropriate irradiation conditions are selected according to the radiation absorption dose corresponding to each tissue material, including: determining the radiation absorption dose of the region of interest according to the radiation absorption dose corresponding to all tissue materials in the region of interest; and selecting appropriate irradiation conditions according to the radiation absorption dose of the region of interest.

[0186] In one embodiment, generating a treatment plan according to appropriate irradiation conditions includes: determining a corresponding flux according to the appropriate irradiation conditions, and performing dose distribution calculation based on the flux using a Monte Carlo simulation program.

[0187] It should be understood that, although the steps in the flowcharts involved in the above embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0188] Based on the same inventive concept, the embodiment of the present application also provides a treatment plan generation device for implementing the treatment plan generation method involved above. The implementation scheme for solving the problem provided by the treatment plan generation device is similar to the implementation scheme recorded in the treatment plan generation method above, so the specific limitations in one or more treatment plan generation device embodiments provided below can refer to the limitations on the treatment plan generation method above, and will not be repeated here.

[0189] In one embodiment, Figure 5 As shown, a treatment plan generating device is provided, which includes a radiation source module 502, a medical impact data module 504, a dose evaluation module 506, an irradiation condition selection module 508 and a treatment plan generating module 510, wherein:

[0190] The radiation source module 502 is used to establish source term information according to different irradiation conditions.

[0191] The medical image data module 504 is used to obtain tissue material information based on medical image data and establish a three-dimensional voxel tissue model.

[0192] The dose assessment module 506 is used to determine the conjugate flux corresponding to the tissue material according to the tissue material information, and to obtain the radiation absorption dose corresponding to each tissue material by combining the source term information and the conjugate flux corresponding to the tissue material.

[0193] The irradiation condition selection module 508 is used to select at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material.

[0194] The treatment plan generating module 510 is used to generate a treatment plan according to appropriate irradiation conditions.

[0195] Each module in the above-mentioned treatment plan generation device can be implemented in whole or in part by software, hardware or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute the operations corresponding to each module.

[0196] Based on the same inventive concept, an embodiment of the present application further provides a radiotherapy system. The implementation solution for solving the problem provided by the radiotherapy system is similar to the implementation solution recorded in the above-mentioned treatment plan generating method or treatment plan generating device. Therefore, the specific limitations in one or more radiotherapy system embodiments provided below can refer to the limitations on the treatment plan generating method or treatment plan generating device above, and will not be repeated here.

[0197] In one embodiment, Figure 6As shown, a radiotherapy system is provided, which includes a beam generating device 602, a beam adjusting device 604, a treatment plan generating device 606 and a beam controlling device 608, wherein:

[0198] The beam generating device 602 is used to generate a therapeutic beam.

[0199] The beam adjusting device 604 is used to adjust the treatment beam generated by the beam generating device 602 .

[0200] The treatment plan generating device 606 is used to establish source term information according to different irradiation conditions, obtain tissue material information based on medical image data, establish a three-dimensional voxel tissue model, determine the conjugate flux corresponding to the tissue material according to the tissue material information, combine the source term information and the conjugate flux corresponding to the tissue material to obtain the radiation absorption dose corresponding to each tissue material, select at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material, and generate a treatment plan according to the suitable irradiation condition.

[0201] The beam control device 608 is used to retrieve the corresponding treatment plan from the treatment plan generating device 606 and control the beam generating device 602 to execute the treatment plan.

[0202] Based on the same inventive concept, the embodiment of the present application also provides another radiotherapy system, which can be a server, and its internal structure diagram can be as follows: Figure 7 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store data such as tissue material information. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a radiotherapy dose assessment method, an irradiation condition selection method or a treatment plan generation method is implemented.

[0203] Those skilled in the art will understand that Figure 7The structure shown in the figure is merely a block diagram of a portion of the structure related to the scheme of the present application, and does not constitute a limitation on the radiotherapy system to which the scheme of the present application is applied. A specific radiotherapy system may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0204] In one embodiment, a radiotherapy system is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0205] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0206] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive 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 may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0207] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0208] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for assessing radiation therapy dose, It is characterized in that The method comprises: Obtain information about organizational materials; Determining the conjugate flux corresponding to the tissue material according to the tissue material information; Based on the irradiation conditions and in combination with the conjugate flux corresponding to the tissue material, the radiation absorbed dose corresponding to the tissue material under the irradiation conditions is obtained.

2. The method according to claim 1, It is characterized in that Determining the conjugate flux corresponding to the tissue material according to the tissue material information includes: Determining a flux dose conversion factor corresponding to the tissue material according to the element information of the tissue material in the tissue material information; The conjugate flux corresponding to the tissue material is determined according to the flux dose conversion factor corresponding to the tissue material.

3. The method according to claim 2, It is characterized in that The element information includes element composition and element proportion, and determining the flux dose conversion factor corresponding to the tissue material according to the element information of the tissue material in the tissue material information includes: According to the element composition and the element proportion, obtaining the density of each nuclide in the tissue material; Obtaining the flux dose conversion factor corresponding to each nuclide; The flux dose conversion factor corresponding to the tissue material is determined by combining the flux dose conversion factor corresponding to each nuclide and the density of each nuclide.

4. The method according to claim 3, It is characterized in that The flux dose conversion factor corresponding to each nuclide and the density of each nuclide are combined to determine the flux dose conversion factor corresponding to the tissue material, using the following formula: Kerma=∑ρ i ·erma i ; Among them, ρ i represents the density of the ith nuclide, Kerma i Represents the flux dose conversion factor corresponding to the i-th nuclide.

5. The method according to claim 2, It is characterized in that The conjugate flux corresponding to the tissue material is determined according to the flux dose conversion factor corresponding to the tissue material, using the following formula: in, represents the conjugate flux, P 1 and P 2 Represents different particle state parameters, Indicates that it is in P 1 The conjugate flux of particles in the state, Kerma represents the flux dose conversion factor, K * represents the conjugate nucleus, K * ( 2 →P 1 ) indicates that the particle is from P 1 In the state, it reaches P through collision reaction 2 The probability of the state.

6. The method according to claim 1, It is characterized in that The step of obtaining the radiation absorbed dose corresponding to the tissue material under the irradiation condition based on the irradiation condition and in combination with the conjugate flux corresponding to the tissue material comprises: Based on the irradiation condition, determining a source term distribution corresponding to the irradiation condition, wherein the source term distribution is used to characterize a distribution function of a particle source under the irradiation condition; The radiation absorption dose corresponding to the tissue material is obtained according to the source term distribution and the conjugate flux corresponding to the tissue material.

7. A method for selecting irradiation conditions, It is characterized in that The method comprises: Combining the irradiation conditions and the conjugate flux corresponding to the tissue material, the radiation absorbed dose corresponding to each tissue material is obtained; At least one suitable irradiation condition is selected according to the radiation absorption dose corresponding to each tissue material.

8. The method according to claim 7, It is characterized in that The step of selecting at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material comprises: If the radiation absorption doses corresponding to the various tissue materials meet the preset conditions, the irradiation conditions are accepted.

9. The method according to claim 8, It is characterized in that The tissue material at least includes tumor tissue material and important organ tissue material, and if the radiation absorption doses corresponding to the various tissue materials meet the preset conditions, then the irradiation conditions are accepted, including: If the radiation absorption dose corresponding to the tumor tissue material is greater than a first preset threshold, and the radiation absorption dose corresponding to the important organ tissue material is less than a second preset threshold, the irradiation condition is accepted.

10. The method according to claim 7, It is characterized in that Before combining the irradiation conditions and the conjugate flux corresponding to the tissue material to obtain the radiation absorption dose corresponding to each tissue material, the method includes: Based on at least one preset region of interest, a tissue material corresponding to the region of interest is determined.

11. The method according to claim 7, It is characterized in that Before combining the irradiation conditions and the conjugate flux corresponding to the tissue material to obtain the radiation absorption dose corresponding to each tissue material, the method includes: Based on at least one preset region of interest and in combination with the concentration distribution of the targeting element in the region of interest, the tissue material corresponding to the region of interest is determined.

12. The method according to claim 10 or 11, It is characterized in that The step of selecting appropriate irradiation conditions according to the radiation absorption doses corresponding to the various tissue materials comprises: Determining the radiation absorbed dose of the region of interest according to the radiation absorbed doses corresponding to all tissue materials in the region of interest; According to the radiation absorbed dose of the region of interest, appropriate irradiation conditions are selected.

13. A treatment plan generating device, It is characterized in that include: A radiation source module is used to establish source term information according to different irradiation conditions; A medical imaging data module, used to obtain tissue material information based on medical imaging data and establish a three-dimensional voxel tissue model; A dose assessment module, used to determine the conjugate flux corresponding to the tissue material according to the tissue material information, and to obtain the radiation absorption dose corresponding to each tissue material by combining the source term information and the conjugate flux corresponding to the tissue material; An irradiation condition selection module, used to select at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material; The treatment plan generating module is used to generate a treatment plan according to the appropriate irradiation conditions.

14. A radiotherapy system, It is characterized in that include: A beam generating device for generating a therapeutic beam; a beam adjustment device, used for adjusting the therapeutic beam generated by the beam generating device; A treatment plan generating device, used to establish source term information according to different irradiation conditions, obtain tissue material information based on medical image data, establish a three-dimensional voxel tissue model, determine the conjugate flux corresponding to the tissue material according to the tissue material information, combine the source term information and the conjugate flux corresponding to the tissue material to obtain the radiation absorption dose corresponding to each tissue material, select at least one suitable irradiation condition according to the radiation absorption dose corresponding to each tissue material, and generate a treatment plan according to the suitable irradiation condition; The beam control device is used to retrieve the corresponding treatment plan from the treatment plan generating device and control the beam generating device to execute the treatment plan.

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