Radiotherapy dose optimization method and device

Abstract

The present application discloses a method and device for optimizing radiotherapy dose. The method includes: obtaining a first reference dose of a target voxel set and an irradiation dose of the target voxel set; optimizing the irradiation dose of the target voxel set according to the first reference dose and a preset objective function; the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose; and determining that the irradiation dose of the target voxel set reaches the optimized target dose when the objective function meets the set conditions. The present application solves the technical problem of low efficiency of radiation dose optimization caused by excessive reliance on manual debugging.

Description

Technical Field

[0001] The present application relates to the field of radiotherapy dose optimization, and specifically, to a method and device for optimizing radiotherapy dose. Background Art

[0002] The formulation of tumor radiotherapy plan is a relatively complex iterative process. The plan design mainly goes through the processes of target area and organ at risk delineation, irradiation field arrangement (fixed irradiation field or arc), plan optimization, plan evaluation and final dose calculation. The plan optimization process relies heavily on the experience and skills of the physicist. The physicist needs to constantly try to adjust the optimization constraints and parameters according to the doctor's prescription to improve the plan until a relatively satisfactory dose index is achieved. In clinical applications, there is often a practical need for a new plan after making some changes to the existing plan or dose, such as continuing the previous treatment after changing the treatment machine, or requiring a corresponding plan for the dose predicted by the deep learning model. If these are still done in the complete planning mode, the planning efficiency is low or even cannot be completed. At present, there is no better technology for generating plans through dose distribution. Most of the methods used are still similar to the traditional method of adding constraints. This method fails to make full use of the data and information of dose distribution. It only uses some information of dose distribution and converts it into information such as dose volume histogram parameters for adding optimization constraints.

[0003] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0004] The embodiments of the present application provide a method and device for optimizing radiotherapy dose, so as to at least solve the technical problem of low efficiency of radiation dose optimization caused by excessive reliance on manual debugging.

[0005] According to one aspect of an embodiment of the present application, a method for determining a radiotherapy target dose is provided, comprising: obtaining a first reference dose of a target voxel set and an irradiation dose of the target voxel set; optimizing the irradiation dose of the target voxel set according to the first reference dose and a pre-set objective function; wherein the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose; and determining that the irradiation dose of the target voxel set reaches the optimized target dose when the objective function meets a set condition.

[0006] Optionally, the objective function includes at least the following parameters: an importance factor, a local correction factor, and a second reference dose of the target area voxel set at the kth adjustment; wherein the target voxel set includes: a target area voxel set and a target organ voxel set; the importance factor is used to adjust the weight of the second reference dose in the objective function and is positively correlated with the second reference dose; k is a positive integer.

[0007] Optionally, the local correction factor is determined in the following manner, including: determining the local correction factor according to the position vector of the target voxel set and a set acceptance condition of the target voxel set.

[0008] Optionally, the irradiation dose is determined in the following manner, including: determining the irradiation dose according to the irradiation dose corresponding to the flux and the number of fluxes corresponding to the sub-field irradiation area.

[0009] Optionally, the second reference dose is determined in the following manner, including: obtaining the current irradiation dose of the target area voxel set when performing the kth adjustment; determining the dose-volume histogram of the current irradiation dose of the target area voxel set; determining the intersection of a set segment of the dose-volume histogram of the current irradiation dose and the dose-volume histogram of the first reference dose, wherein the dose-volume histogram is used to represent the irradiation dose corresponding to the voxel set; and determining the second reference dose based on the dose value corresponding to the intersection.

[0010] Optionally, the second reference dose is also determined in the following manner: when the intersection does not exist, the dose value corresponding to the set point of the dose volume histogram of the current irradiation dose of the target area voxel set is determined as the second reference dose.

[0011] Optionally, before obtaining the first reference dose of the target voxel set and the irradiation dose of the target voxel set, the method also includes: sampling the target area and the target organ to determine the target voxel set; projecting the target voxel set to determine a dose deposition matrix, and determining the irradiation dose corresponding to the flux through the dose deposition matrix.

[0012] According to another aspect of an embodiment of the present application, a device for optimizing a radiotherapy target dose is also provided, including: an acquisition module, used to acquire a first reference dose of a target voxel set and an irradiation dose of the target voxel set; an optimization module, used to optimize the irradiation dose of the target voxel set according to the first reference dose and a pre-set objective function; wherein the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose; and a determination module, used to determine that the irradiation dose of the target voxel set reaches the optimized target dose when the objective function meets a set condition.

[0013] According to another aspect of the embodiment of the present application, a non-volatile storage medium is also provided, wherein the non-volatile storage medium includes a stored program, wherein when the program is running, the device where the non-volatile storage medium is located is controlled to execute the above-mentioned radiotherapy dose optimization method.

[0014] According to another aspect of the embodiments of the present application, there is also provided an electronic device, including a memory and a processor; the processor is used to run a program, wherein the program executes the above-mentioned radiotherapy dose optimization method when running.

[0015] In an embodiment of the present application, a first reference dose of a target voxel set and an irradiation dose of the target voxel set are obtained; the irradiation dose of the target voxel set is optimized according to the first reference dose and a preset objective function; wherein the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose; when the objective function reaches a set condition, a manner in which the irradiation dose of the target voxel set reaches an optimized target dose is determined, and the irradiation dose of the target voxel set is optimized by using the first reference dose and the preset objective function until the optimized target dose is reached, thereby achieving the purpose of automatically optimizing the radiotherapy dose, thereby realizing the technical effect of improving the efficiency of radiation dose optimization, and further solving the technical problem of low efficiency of radiation dose optimization caused by excessive reliance on manual debugging. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 A hardware structure block diagram of a computer terminal (or mobile device) for implementing a method for optimizing radiotherapy dose is shown;

[0018] Figure 2 is a schematic diagram of an optional radiotherapy dose optimization method according to an embodiment of the present application;

[0019] Figure 3 is a schematic diagram of an optional dose deposition matrix according to an embodiment of the present application;

[0020] Figure 4 This is a schematic diagram of an optional radiotherapy dose optimization device according to an embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0022] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0023] For the convenience of description, some nouns or terms involved in the embodiments of the present application are explained below:

[0024] DVH: dose volume histogram; BEV: beam direction view; bixel: pixel point of beam direction view projection; voxel: voxel.

[0025] According to an embodiment of the present application, a method embodiment of a method for optimizing a radiotherapy dose is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0026] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Figure 1 FIG. 1 shows a hardware structure block diagram of a computer terminal (or mobile device) for implementing a method for optimizing radiotherapy dose. Figure 1As shown, the computer terminal 10 (or mobile device 10) may include one or more (102a, 102b, ..., 102n are used to illustrate) processors 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA), a memory 104 for storing data, and a transmission module 106 for communication functions. In addition, it may also include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of the I / O interface), a network interface, a power supply and / or a camera. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the above electronic device. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown.

[0027] It should be noted that the one or more processors 102 and / or other data processing circuits described above may generally be referred to herein as "data processing circuits". The data processing circuits may be embodied in whole or in part as software, hardware, firmware, or any other combination thereof. In addition, the data processing circuit may be a single independent processing module, or may be incorporated in whole or in part into any of the other components in the computer terminal 10 (or mobile device). As described in the embodiments of the present application, the data processing circuit acts as a processor control (e.g., selection of a variable resistor terminal path connected to an interface).

[0028] The memory 104 can be used to store software programs and modules of application software, such as program instructions / data storage devices corresponding to the method for optimizing the radiotherapy dose in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the software programs and modules stored in the memory 104, that is, to implement the above-mentioned method for optimizing the radiotherapy dose. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories may be connected to the computer terminal 10 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0029] The transmission module 106 is used to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of the computer terminal 10. In one example, the transmission module 106 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission module 106 can be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0030] The display may be, for example, a touch screen liquid crystal display (LCD) that enables a user to interact with a user interface of the computer terminal 10 (or mobile device).

[0031] Figure 2 According to the method for optimizing the radiotherapy dose of the embodiment of the present application, Figure 2 As shown, the method comprises the following steps:

[0032] Step S202, obtaining a first reference dose of a target voxel set and an irradiation dose of the target voxel set;

[0033] Step S204, optimizing the irradiation dose of the target voxel set according to the first reference dose and a preset objective function; wherein the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose;

[0034] Step S206 , when the objective function meets the set condition, determining that the irradiation dose of the target voxel set reaches the optimized target dose.

[0035] Through the above steps, the irradiation dose of the target voxel set can be optimized through the first reference dose and the pre-set objective function until the optimized target dose is reached, thereby achieving the purpose of automatically optimizing the radiotherapy dose, thereby achieving the technical effect of improving the efficiency of radiation dose optimization, and further solving the technical problem of low efficiency of radiation dose optimization caused by excessive reliance on manual debugging.

[0036] It should be noted that the first reference dose can be obtained through a pre-trained dose prediction model, and the training data set of the prediction model can be composed of dose distribution data of historical cases; in actual operation, for the same case, treatment is performed again. If the current treatment plan has not changed, the irradiation dose corresponding to the previous treatment plan can be used as the first reference dose for the current treatment, or a dose distribution corresponding to the above-mentioned target voxel set after resampling can be obtained. Dose in this application specifically refers to: ionizing radiation dose, that is, the amount of ionizing radiation generated in a medium when the medium is irradiated by rays or particle beams that can generate ionizing radiation.

[0037] It should be further explained that the above-mentioned setting conditions include: the objective function converges to a set error range or the number of optimization iterations reaches a set maximum number of iterations.

[0038] In specific application scenarios, the irradiation dose can be adjusted by adjusting the leaf position of the multi-page grating and the beam irradiation to formulate the execution sequence of the target dose and achieve the target dose distribution. The specific sequence includes but is not limited to: adjusting the gantry angle, the collimator angle, the position of each leaf in the multi-page grating, and the weight of each control point or sub-field.

[0039] In some embodiments of the present application, the objective function includes at least the following parameters: an importance factor, a local correction factor, and a second reference dose of the target area voxel set at the kth adjustment; wherein the target voxel set includes: a target area voxel set and a target organ voxel set; the importance factor is used to adjust the weight of the second reference dose in the objective function and is positively correlated with the second reference dose; k is a positive integer.

[0040] Specifically, the expression of the objective function is as follows:

[0041]

[0042] Where K(k) = ceil(N·k / n) / N, k = 1, 2, ..., n; k is the current adjustment number; n is the total adjustment number; N is the adjustment order parameter of the objective function weight change during the adjustment process; sgn is the sign function, ceil is the upward rounding function, min and max are the minimum and maximum functions respectively; λ is the target area importance factor and (0 < λ < 1); α is the penalty index (can be a quadratic penalty); d i is the irradiation dose of voxel i; D i is the first reference dose for voxel i; is the second reference dose of the target voxel set during the kth optimization; Γ(i) is the local correction factor at voxel i; V T is the target voxel set, V O is the target organ voxel set.

[0043] It should be noted that the target organ can be an organ at risk, and the target importance factor λ is used to adjust the relative weight between the target and the organ at risk. For scenarios that place more emphasis on the target dose characteristics, the target importance factor can be set larger. In the case where more emphasis is placed on the protection of organs at risk, the target importance factor can be set smaller. Specifically, it is determined according to the tumor type. For a certain type of tumor, some cases can be selected first, and the target importance factor λ can be debugged until it meets the physicist's planning habits, that is, this type of disease is determined to be fixed and use this value.

[0044] The penalty index α measures the difference by using the different speed changes of different power functions in mathematics. The farther away from the target value, the greater the penalty.

[0045] In some optional ways, in certain areas of the target voxel set, when the difference between the current irradiation dose and the reference dose is large, the penalty for the area can be strengthened by adjusting the value of the local correction factor, so as to increase the irradiation intensity of the area and make the distribution of the current irradiation dose and the reference dose more consistent. Specifically, the local correction factor only works in a small range in the neighborhood of voxel i, so it can only be adjusted locally. Moreover, the value of the local correction factor is related to the dose and position error at that point. The smaller the dose and position error, the smaller the value of the local correction factor, and the weaker the penalty. In the optimization, the algorithm will adjust the flux distribution or the movement of the multi-leaf grating to make the dose and position error at that point as small as possible, thereby achieving the purpose of local adjustment.

[0046] In some embodiments of the present application, the local correction factor is determined in the following manner: the local correction factor is determined according to the position vector of the target voxel set and the set acceptance condition of the target voxel set.

[0047] Specifically, the first method is to directly take a random constant, for example: the local correction factor Γ(i) = c at voxel i, where c is a constant. However, this method is essentially equivalent to not considering the local correction of the objective function. The second method is to use the gamma value to calculate the value of D i is the first reference dose, and the gamma value under the acceptance condition of (L mm, D%) is calculated as follows:

[0048]

[0049] In the formula, is the position vector of voxel j when the acceptance condition is met, is the position vector of the point in the L mm neighborhood of voxel i, d j is the irradiation dose of voxel j, S iis the set of all voxels that meet the acceptance condition when the voxel i is under the acceptance condition (L mm, D%).

[0050] It should be noted that the L in the acceptance condition refers to the point within L mm from the target voxel point, D refers to the maximum acceptable error percentage, and the acceptance condition (L mm, D%) means that only the points in the neighborhood of a sphere with a radius of L mm centered on the point are considered, and the local correction factor value at the point is calculated using D% as the error acceptance degree, and the error acceptance degree is pre-set.

[0051] In some embodiments of the present application, the irradiation dose is determined in the following manner: the irradiation dose is determined according to the irradiation dose corresponding to the flux and the number of fluxes corresponding to the sub-field irradiation area.

[0052] Specifically, the first method is: flux optimization, that is, the irradiation dose d of voxel i is i It is expressed as a function of flux X, with flux X as the irradiation dose d of voxel i i The optimal decision variable is the irradiation dose d of voxel i. i The calculation formula is as follows:

[0053]

[0054] Where P is the projection of BEV (beam eye view), x j is the flux passing through the jth bixel (projected pixel point), D j,i The dose engine calculates the irradiation dose of voxel i by the flux of the jth bixel in advance.

[0055] It should be noted that the flux of the j-th bixel refers to the intensity of the beam emitted from the radiation source and passing through the j-th bixel.

[0056] After the target flux that meets the requirements is obtained through optimization, the positions of the multi-page grating leaves and the intensity of the sub-fields are generated through the leaf sequence algorithm.

[0057] It should be noted that the dose engine is a pre-set algorithm for calculating the irradiation dose, and the multi-page grating blades are used to adjust the irradiation field, where the irradiation field is a set formed by a series of multi-page grating movements and beam irradiation in one direction. In the case of volumetric intensity-modulated radiotherapy, the irradiation field refers to the set of gantry movement within the set arc range, multi-page grating movement and beam irradiation; the sub-field is a component of the above-mentioned irradiation field, specifically refers to the irradiation of a set amount when the gantry angle and the grating position are set, which is called a sub-field.

[0058] The irradiation dose can also be confirmed by a second method: direct subfield optimization. Specifically, the irradiation dose of voxel i is calculated as follows:

[0059]

[0060] In the formula, K is the sub-field set, x w (k) is the weight of subfield k, P is the BEV projection, D j,i is the irradiation dose of voxel i by the flux of the jth bixel calculated in advance by the dose engine, x p (k) is the leaf position of the multi-page grating corresponding to sub-field k, Φ j (x p (k)) represents the proportion of the j-th bixel in subfield k.

[0061] It should be noted that the above ratio specifically refers to the ratio of the sub-field shape formed by the positions of multiple grating blades. If all are within the sub-field, its value is 1, and if all are outside, its value is 0. The bixel in the boundary area is within the sub-field, and the value is between 0 and 1 based on the ratio of the position of the bixel in the sub-field.

[0062] In some embodiments of the present application, the second reference dose is determined in the following manner: obtaining the current irradiation dose of the target area voxel set when performing the kth adjustment; determining the dose-volume histogram of the current irradiation dose of the target area voxel set; determining the intersection of a set segment of the dose-volume histogram of the current irradiation dose and the dose-volume histogram of the first reference dose, wherein the dose-volume histogram is used to represent the irradiation dose corresponding to the voxel set; and determining the second reference dose based on the dose value corresponding to the intersection.

[0063] Specifically, when the objective function is used for the kth adjustment, the intersection value of the D90-D100 segment of the dose volume histogram DVH of the current irradiation dose of the target area voxel set and the DVH corresponding to the first reference dose is set as the second reference dose.

[0064] In some embodiments of the present application, when the intersection does not exist, the dose value corresponding to the set point of the dose volume histogram of the current irradiation dose of the target area voxel set is determined as the second reference dose.

[0065] For example, the D50 value of the dose volume histogram DVH of the current irradiation dose of the target area voxel set may be taken as the second reference dose, which may be specifically set according to actual needs.

[0066] In some embodiments of the present application, before obtaining the first reference dose of the target voxel set and the irradiation dose of the target voxel set, the method also includes: sampling the target area and the target organ to determine the target voxel set; projecting the target voxel set to determine a dose deposition matrix for determining the irradiation dose corresponding to the unit flux.

[0067] Specifically, for example, after the irradiation field is arranged, the target area and each critical organ are sampled (without limiting the sampling method), the number of samples is determined according to the volume and the number that the computing memory can bear, and then the resolution is calculated according to the number of samples to obtain an optimized voxel set, and the BEV is projected to obtain a bixel (pixel point) set, and finally the dose engine is called to calculate the dose deposition matrix, such as Figure 3 As shown, each bixel in the matrix corresponds to an irradiation dose.

[0068] It should be noted that organ-threatening

[0069] The present application also provides a device for optimizing radiotherapy dose, such as Figure 4 As shown, the device comprises:

[0070] An acquisition module 40 is used to acquire a first reference dose of a target voxel set and an irradiation dose of the target voxel set; an optimization module 42 is used to optimize the irradiation dose of the target voxel set according to the first reference dose and a preset objective function; wherein the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose; a determination module 44 is used to determine that the irradiation dose of the target voxel set reaches the optimized target dose when the objective function meets the set conditions.

[0071] The optimization module 42 includes: an objective function determination module; the objective function determination module is used to determine the second reference dose of the target area voxel set at the kth adjustment based on the importance factor, the local correction factor, and the second reference dose of the target area voxel set; wherein the target voxel set includes: a target area voxel set and a target organ voxel set; the importance factor is used to adjust the weight of the second reference dose in the objective function and is positively correlated with the second reference dose; k is a positive integer.

[0072] The objective function determination module includes: a local correction factor determination submodule, an irradiation dose determination submodule, and a second reference dose determination submodule; the local correction factor determination submodule is used to determine the local correction factor according to the position vector of the target voxel set and the set irradiation conditions of the target voxel set; the irradiation dose determination submodule is used to determine the irradiation dose according to the irradiation dose corresponding to the flux and the number of fluxes corresponding to the sub-field irradiation area; the second reference dose determination submodule is used to obtain the current irradiation dose of the target area voxel set when performing the kth adjustment; determine the dose-volume histogram of the current irradiation dose of the target area voxel set; determine the intersection of the set segment of the dose-volume histogram of the current irradiation dose and the dose-volume histogram of the first reference dose, wherein the dose-volume histogram is used to represent the irradiation dose corresponding to the voxel set; and determine the second reference dose according to the dose value corresponding to the intersection.

[0073] The second reference dose determination submodule comprises a secondary determination unit, which is used to determine the dose value corresponding to the set point of the dose volume histogram of the current irradiation dose of the target area voxel set as the second reference dose when the intersection does not exist.

[0074] The device also includes a dose determination module, which is used to sample the target area and the target organ to determine the target voxel set; project the target voxel set to determine a dose deposition matrix for determining an irradiation dose corresponding to the flux.

[0075] An embodiment of the present application also provides a non-volatile storage medium, which includes a stored program, wherein when the program is running, the device where the non-volatile storage medium is located is controlled to execute the above-mentioned radiotherapy target dose determination method, including: obtaining a first reference dose of a target voxel set and an irradiation dose of the target voxel set; optimizing the irradiation dose of the target voxel set according to the first reference dose and a preset objective function; wherein the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose; and when the objective function meets the set conditions, determining that the irradiation dose of the target voxel set reaches the optimized target dose.

[0076] An embodiment of the present application also provides an electronic device, including a memory and a processor; the processor is used to run a program, wherein the program executes the above-mentioned radiotherapy dose optimization method when running.

[0077] This application performs automatic optimization based on the reference dose, thereby realizing the function of automatic planning. There is no need for physicists to manually add optimization constraints and adjust parameters, which can simplify the planning process of physicists and improve the efficiency of planning. At the same time, on the one hand, the reference dose is penalized, and on the other hand, the nominal reference dose is penalized, which can make the optimization results approach the reference dose continuously and optimize in a direction better than the reference dose.

[0078] The weight of the penalty item of the reference dose of the target area in the early stage is relatively large, and the weight of the penalty item of the reference dose in the later stage is relatively large. In this way, in the optimization process, the target dose is quickly approached in the early stage, a preliminary suboptimal solution is obtained as soon as possible, and then the reference dose is continuously approached. A local penalty factor is used to dynamically penalize the dose in a small range, so that the dose distribution is more consistent with the reference dose.

[0079] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0080] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0081] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0082] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0083] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0084] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.

[0085] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for optimizing radiotherapy dose, characterized in that: include: Acquiring a first reference dose of the target voxel set and an irradiation dose of the target voxel set; Optimizing the irradiation dose of the target voxel set according to the first reference dose and a preset objective function; wherein the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose; When the objective function meets the set condition, determining that the irradiation dose of the target voxel set reaches the optimized target dose; The objective function includes at least the following parameters: importance factor, local correction factor, and the second reference dose of the target voxel set at the kth adjustment; wherein the target voxel set includes: the target voxel set and the target organ voxel set; the importance factor is used to adjust the weight of the second reference dose in the objective function and is positively correlated with the second reference dose; k is a positive integer; The local correction factor is determined in the following manner, including: determining the local correction factor according to the position vector of the target voxel set and the set acceptance condition of the target voxel set.

2. The method according to claim 1, characterized in that The irradiation dose is determined by the following methods, including: The irradiation dose is determined according to the irradiation dose corresponding to the flux and the number of fluxes corresponding to the sub-field irradiation area.

3. The method according to claim 1, characterized in that The second reference dose is determined by the following method, including: Acquire the current irradiation dose of the target area voxel set when performing the kth adjustment; Determining a dose volume histogram of a current irradiation dose of the target area voxel set; Determining an intersection point of a set section of a dose-volume histogram of the current irradiation dose and a dose-volume histogram of the first reference dose, wherein the dose-volume histogram is used to represent an irradiation dose corresponding to a set of voxels; The second reference dose is determined according to the dose value corresponding to the intersection point.

4. The method according to claim 3, characterized in that The second reference dose is also determined by: In the case that the intersection point does not exist, the dose value corresponding to the set point of the dose volume histogram of the current irradiation dose of the target area voxel set is determined as the second reference dose.

5. The method according to claim 2, characterized in that: Before acquiring the first reference dose of the target voxel set and the irradiation dose of the target voxel set, the method further includes: Sampling the target area and the target organ to determine the target voxel set; The target voxel set is projected to determine a dose deposition matrix, and an irradiation dose corresponding to the flux is determined by the dose deposition matrix.

6. A device for optimizing radiotherapy target dose, characterized in that: include: An acquisition module, used for acquiring a first reference dose of a target voxel set and an irradiation dose of the target voxel set; an optimization module, configured to optimize the irradiation dose of the target voxel set according to the first reference dose and a preset objective function; wherein the value of the objective function is positively correlated with the difference between the irradiation dose of the target voxel set and the first reference dose; A determination module, configured to determine, when the objective function meets a set condition, that the irradiation dose of the target voxel set reaches an optimized target dose; The objective function includes at least the following parameters: importance factor, local correction factor, and the second reference dose of the target voxel set at the kth adjustment; wherein the target voxel set includes: the target voxel set and the target organ voxel set; the importance factor is used to adjust the weight of the second reference dose in the objective function and is positively correlated with the second reference dose; k is a positive integer; The local correction factor is determined in the following manner, including: determining the local correction factor according to the position vector of the target voxel set and the set acceptance condition of the target voxel set.

7. A non-volatile storage medium, characterized in that: The non-volatile storage medium includes a stored program, wherein when the program is executed, the device where the non-volatile storage medium is located is controlled to execute the method for optimizing the radiotherapy dose according to any one of claims 1 to 5.

8. An electronic device, characterized in that: It comprises a memory and a processor; the processor is used to run a program, wherein when the program is run, the method for optimizing the radiotherapy dose described in any one of claims 1 to 5 is executed.

Images