Radiotherapy system and therapy plan generation method therefor

Abstract

To provide a radiotherapy system and a therapy plan generation method therefor which can improve the accuracy of model establishment and dosage calculation, and facilitate rapid formulation of the therapy plan.SOLUTION: A radiotherapy system comprises a beam irradiation apparatus, a therapy plan module, and a control module. A tissue model template database of an irradiated body is stored in the therapy plan module; the therapy plan module performs dosage simulation calculation according to the tissue model template database, medical imaging data of the irradiated part, and a parameter of the beam for therapy generated by the beam irradiation apparatus, and generates a therapy plan. The control module retrieves, from the therapy plan module, the therapy plan corresponding to the irradiated body, and controls the beam irradiation apparatus to irradiate the irradiated body according to the therapy plan determined by the therapy plan generation method.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] One aspect of the present invention relates to a radiation therapy system, and another aspect of the present invention relates to a treatment plan generation method. In particular, the present invention relates to a treatment plan generation method for a radiation therapy system. [Background technology]

[0002] With the development of atomic science, radiation such as cobalt-60, linear accelerators, and electron beams Radiation therapy has already become one of the main methods of cancer treatment. However, conventional photon or electron The therapy is limited by the physical conditions of the radiation itself, killing tumor cells and The radiation damages many normal tissues. The degree of sensitivity of tumor cells to radiation also varies. Therefore, conventional radiation therapy is not effective against malignant tumors with high radiation resistance (e.g., glioblastoma multiforme). Glioblastoma multiforme, melanoma ) treatment is not very effective.

[0003] To reduce radiation damage to the normal tissue surrounding the tumor, chemotherapy is used. The concept of targeted therapy in the erapy is being used in radiation therapy. Currently, the relative biological effectiveness (RBI) of Radiation sources with high radioactivity effectiveness (RBE) are being actively developed. (For example, proton therapy, heavy particle therapy, neutron capture therapy, etc.). Of these, neutron capture therapy is a combination of the above two concepts. For example, boron neutron capture therapy (Bor In Neutron Capture Therapy (BNCT), boron-containing The drug specifically collects in tumor cells, and by combining this with precise beam control, it is possible to achieve a level of efficacy that is superior to conventional radiation therapy. It offers a better cancer treatment option compared to radiation.

[0004] 3D models are widely used in the fields of scientific experiment analysis and simulation. For example, in the field of nuclear radiation and protection, it is used to estimate the absorbed dose in the human body under certain radiation conditions. Computer technology is constantly being used to simulate the patient's condition and help doctors develop treatment plans. We use techniques to perform various processing on medical image data, which is required for Monte Carlo software. We established the necessary accurate lattice model and simulated it in combination with Monte Carlo software. In the field of neutron capture therapy, Monte Carlo simulations are performed based on medical imaging data. When establishing the necessary grid model for the Carlo software and performing dose calculation and evaluation, the model In the model, basic biological information reflected by each grid, such as tissue type and boron concentration information, is defined. The accuracy and precision of the information determines the reliability of the dose calculation results. In the process of drawing up a plan, the delineation of the regions of interest and the definition of the basic biometric information of each region are generally performed as follows: Both of these methods require a lot of time and are based on models directly converted from medical image data. The models are often not accurate enough, affecting the accuracy of the calculated dose distribution. can.

[0005] Therefore, there is a need to provide a radiation therapy system and method for generating a treatment plan therefor. Summary of the Invention

[0006] To overcome the deficiencies of the prior art, a radiation therapy system according to one aspect of the present invention includes a beam The beam delivery device includes a treatment beam delivery device, a treatment planning module, and a control module. The beam is generated and irradiated to the target body to form the target area. a tissue model template database of the irradiated object; and a treatment planning module. the tissue model template database, the medical image data of the irradiated area, and A dose simulation is performed based on the parameters of the treatment beam generated by the beam irradiation device. The control module performs a simulation calculation and generates a treatment plan. The treatment plan corresponding to the irradiated object is retrieved from a module, and the treatment plan is performed according to the treatment plan. The beam irradiation device is controlled so as to irradiate the irradiation target by the tissue model template. The database is set in advance, and the established data is used depending on the individual experience of the operator, such as a doctor. Prevents inaccuracies in the model and dose calculations and also prevents the biobasic nature of the lattice in the model. Avoid spending a lot of time and energy defining information.

[0007] Preferably, the tissue model template database includes ROI template data A base and a material template database, the ROI refers to a region of interest, The ROI template database must be defined for different irradiated regions. The ROI type is set, and the material template database is a tissue type template. the tissue type template database includes a tissue type template database for each of the ROIs; For each voxel, a corresponding tissue type is defined. The model has tissue type information. The established geometric model provides a more accurate elemental composition that is better reflected by medical imaging data. The ROI type can be preset and the operator (e.g. a doctor) can select the ROI type based on the actual situation. Due to differences in individual experience, the ROIs established may be inaccurate or incomplete. This prevents inaccurate models and dose calculations, and also reduces the time required to select the ROI type. This avoids the time and effort required to accommodate different ROIs and different tissue types within the ROIs. The element composition to be used is preset, and depending on the individual experience of the operator such as a doctor, it is either given manually or Because there are differences in elemental composition of the same ROI or tissue type obtained by automatic conversion , to prevent the established model and dose calculation from being inaccurate, and to prevent the elemental composition in the ROI from being inaccurate. This avoids spending a lot of time and energy on creating or converting

[0008] Further, the treatment planning module may include a database of ROI templates and a database of tissue Based on the type template database, a type template corresponding to the medical image data of the irradiated area is Establish a three-dimensional voxel prosthetic tissue model and determine the parameters of the treatment beam. Based on the data and the 3D voxel prosthesis tissue model, a Monte Carlo simulation was performed. The physical radiation when the treatment beam is irradiated to the irradiation site by the simulation program. The dose rate distribution is simulated.

[0009] Preferably, the material template database comprises biological effect template data. the biological effect template database includes a voxel base within each of the ROIs; For each of the treatment units, corresponding biological effect data is defined, and the treatment planning module The simulated physical dose rate distribution and the 3D voxel prosthesis tissue model When the therapeutic beam is irradiated to the irradiated area based on the biological effect data of the Calculate the equivalent dose rate distribution for each ROI and for different tissue types in the ROI. Biological effect data is preset, and the difference in the individual experience of the operator, such as a physician, may be caused by the given There are differences in biological effect data for the same ROI or tissue type, so the established models Prevents inaccurate model and dose calculations and also provides biological effect data within the ROI. Avoid expending large amounts of time and energy on giving.

[0010] More preferably, the radiation therapy system is a boron neutron capture therapy system; The treatment planning module calculates, for each voxel within each ROI, a corresponding boron concentration The degree of the 3D voxel process is defined by a Monte Carlo simulation program. Boron dose per unit time (D B ), fast neutron dose (D f ), Thermal neutron dose (D th ) and photon dose (D γ The model simulates the organization It also has boron concentration information, and the concentration of boron-containing drugs in each tissue can be clearly understood. This allows for more realistic simulation of the actual situation when performing irradiation simulation for boron neutron capture therapy. can be reflected in.

[0011] Further, the material template database includes a boron concentration ratio template database. and the boron concentration ratio template database further comprises: For each unit, the ratio of the corresponding tissue boron concentration to the blood boron concentration is defined.

[0012] Additionally, the material template database may include a biological effect template database. wherein the biological effect template database comprises a voxel-by-voxel representation within each of the ROIs. For each, the corresponding CBE and RBE f , R.B.E. th , and RBE γ Define and use Eq. Calculate the equivalent dose rate D of the three-dimensional voxel prosthetic tissue model by D(Gy)=CBE(1 / ppm)×B con (ppm) x D B (Gy)+RBE f ×D f (Gy)+RBE th ×D th (Gy)+RBE γ ×D γ (Gy) (Equation 1) where CBE is the compound biological effect of a unit concentration of a boron-containing drug, and B con is the tissue boron concentration and RBE f is the relative biological effectiveness of fast neutrons, and RB E th is the relative biological effectiveness of thermal neutrons, RBE γ is the relative biological effectiveness of photons The result is.

[0013] Furthermore, the treatment planning module samples and simulates different irradiation angles. and at least one irradiation angle is suitably selected based on the equivalent dose rate distribution calculated by the method. Select .

[0014] Preferably, the beam irradiation device further includes a collimator. A collimator template database is stored in the The database stores at least some of the parameters of the treatment beam corresponding to different collimators. Define it piecemeal.

[0015] A method for generating a treatment plan for a radiation therapy system according to another aspect of the present invention includes: Based on the rate database, 3D voxel images corresponding to the medical image data of the irradiated area are Establishing a prosthetic tissue model and running a Monte Carlo simulation program By defining the beam parameters in the ram and sampling different irradiation angles, A step of performing a dose simulation calculation and suitably selecting an irradiation angle based on the calculation result. and generating a treatment plan. The 3D voxel process is preset and established according to the individual experience of the doctor or other operator. Prevents inaccuracies in the stasis tissue model and dose calculations and To avoid spending a lot of time and energy on defining the biometric basic information of the lattice.

[0016] Preferably, the radiation therapy system further comprises a collimator. In the simulation program, different collimator templates are generated based on the collimator template database. The beam parameters corresponding to the collimator are defined as follows:

[0017] More preferably, the tissue model template database is a ROI template database. a tissue type template database, and the ROI is a region of interest. and generating medical image data of the irradiated area based on the tissue model template database. The step of establishing a three-dimensional voxel prosthetic tissue model corresponding to the data includes: A step of reading medical image data of the irradiation site and establishing a three-dimensional medical image voxel model. and calling up a ROI template database for the irradiated area. Define the boundaries of the ROI set in the ROI template database of the injection site, or and calling up a tissue type template database for the irradiated area. providing a tissue type for each voxel in each of the ROIs; providing a cell-by-cell tissue boron concentration; and determining whether said three-dimensional voxel prosthetic tissue is and establishing a model. Due to differences in personal experience, the ROIs defined may be inaccurate or incomplete, and the established 3 2D prosthesis tissue model and dose calculations are prevented from being inaccurate, and ROI It avoids spending a lot of time and energy on selecting the type and allows you to select the type of each ROI and the different The elemental composition corresponding to the various tissue types is preset, and the system is resistant to differences in the personal experience of doctors and other operators. Therefore, the same ROI or source of the same tissue type obtained by manual or automatic conversion can be used. Due to differences in elemental composition, established 3D prosthetic tissue models and dose calculations are not valid. It is also useful for providing or converting the elemental composition within the ROI. This avoids spending a lot of time and energy.

[0018] Furthermore, the tissue model template database includes boron concentration ratio template data a base, and based on the boron concentration ratio template database of the irradiated portion, By providing the ratio of the tissue boron concentration to the blood boron concentration for each voxel in the ROI, This gives the voxel-by-voxel tissue boron concentration within each ROI.

[0019] Furthermore, the beam parameters are defined in the Monte Carlo simulation program. The dose simulation calculation is performed by sampling different irradiation angles. The 3D voxel prosthetic tissue model is then The boron dose (D B ), fast neutron dose (D f ), thermal neutron dose (D th ) and photon dose (D γ ) and simulating the therapeutic dose using Equation 1. Equivalent dose per unit time for each voxel of the tissue model at a defined beam exposure and calculating the dose rate D, D(Gy)=CBE(1 / ppm)×B con (ppm) x D B (Gy)+RBE f ×D f (Gy)+RBE th ×D th (Gy)+RBE γ ×D γ (Gy) (Equation 1) where CBE is the compound biological effect of a unit concentration of a boron-containing drug, and B con is the tissue boron concentration and RBE f is the relative biological effectiveness of fast neutrons, and RB E th is the relative biological effectiveness of thermal neutrons, RBE γ is the relative biological effectiveness of photons and the tissue model template database is a biological effect template database. and based on the biological effect template database of the irradiated area, Voxel-wise CBE and RBE in each ROI f , R.B.E. th , and RBE γ Give The biological effect data corresponding to each ROI and the different tissue types in the ROI are predefined. Due to differences in the personal experience of the operator, such as a physician, the same ROI or tissue type may be used. Due to differences in the biological efficacy data of different types of prosthesis, This prevents inaccurate dose and trace calculations and provides biological effect data within the ROI. This avoids spending a lot of time and energy on

[0020] Furthermore, the treatment plan generation method includes sampling different irradiation angles to perform a simulation. Preferably selected based on the distribution of the calculated equivalent dose rate D and at least one irradiation angle The method further includes the step of selecting a degree.

[0021] The radiation therapy system and the treatment plan generation method thereof of the present invention are This can improve accuracy and aid in the rapid development of treatment plans. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic diagram of a boron neutron capture reaction. [Diagram 2] This is the nuclear reaction equation for neutron capture in 10B(n,α)7Li. [Diagram 3] 1 is a block diagram of a neutron capture therapy system according to an embodiment of the present invention. [Figure 4] 4 is a flow diagram of a method by which a treatment planning module generates a treatment plan, according to an embodiment of the present invention. [Diagram 5] FIG. 2 is a block diagram of a treatment planning module according to one embodiment of the present invention. [Figure 6] 1 is a flow diagram of a method for establishing a three-dimensional voxel prosthetic tissue model according to an embodiment of the present invention. [Figure 7] 4 is a flow diagram of a method for dose simulation calculations, according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The present invention will now be described in more detail with reference to the accompanying drawings, so that those skilled in the art can easily understand the present invention. If so, the disclosure may be implemented by reference to the text of the specification.

[0024] Preferably, a neutron capture therapy system and a treatment plan generation method thereof are embodiments of the present invention. Neutron capture therapy, and in particular boron neutron capture therapy, will be briefly explained below.

[0025] Neutron capture therapy has been increasingly used in recent years as an effective means of cancer treatment. Of these, boron neutron capture therapy has become the most common. The neutrons used can be provided by a nuclear reactor or an accelerator. Take the example of boron neutron capture therapy. The basic module of accelerator boron neutron capture therapy is generally Accelerators, targets, and heat removal devices used to accelerate particles (protons, deuterium nuclei, etc.) The beam shaping assembly includes a beam removal system and a beam shaping assembly. Neutrons are generated by the use of the neutron generator, and the required neutron yield and energy, the available accelerated charged particle The energy and current of the target, as well as the physical and chemical properties of the metal target, determine the appropriate A nuclear reaction is selected. The most commonly studied nuclear reactions are 7 Li(p,n) 7 Be and 9 Be(p,n) 9 B, and both of these reactions are endothermic. The reactions have energy thresholds of 1.881 MeV and 2.055 MeV, respectively. The ideal neutron source for neutron capture therapy is epithermal neutrons at the keV energy level. In the study, the impact of protons with energies slightly above the threshold on a lithium target produced a relatively large amount of Low energy neutrons are produced, making them suitable for clinical use without the need for extensive moderation. However, the two targets, lithium (Li) and beryllium (Be), are below the threshold. Since the cross section interacting with the energetic protons is not large, in order to ensure a sufficient neutron flux, Generally, nuclear reactions are caused by protons with relatively high energy.

[0026] Boron Neutron Capture Therapy y, BNCT) is boron ( 10 B) The drug has a large capture cross section for thermal neutrons. Using sex, 10 B(n,α) 7 Li neutron capture and fission reactions 4 He and 7 Li Figure 1 and Figure 2 show schematic diagrams of the boron neutron capture reaction, respectively. and 10 B(n,α) 7 The nuclear reaction formula for Li neutron capture is shown below. The two heavy charged particles have an average energy of The energy is about 2.33 MeV, and the linear energy transfer is high. y Transfer (LET) and short range. The deposition and range are 150keV / μm and 8μm, respectively. 7 In the case of Li charged particles, The combined range of the two particles is close to the size of a cell. This allows radiation damage to be limited to the cellular level. Boron-containing drugs can be selectively administered to tumor cells. By concentrating the neutrons in a small area and combining them with an appropriate neutron source, it is possible to target tumor cells without causing significant damage to normal tissue. This achieves the goal of partially killing the

[0027] The Monte Carlo method calculates the collision trajectories and energy distribution of nuclear particles in a three-dimensional space inside the radiation target. It can accurately simulate the fabric and is suitable for specific radiation conditions in neutron capture therapy. Simulates the absorbed dose in the human body under certain conditions to help doctors develop treatment plans In order to do so, we always use computer technology to process medical image data in various ways, Establish accurate lattice models required for Monte Carlo software and It is necessary to perform simulation calculations in combination with the medical image data. Imaging (Magnetic Resonance Imaging, MRI), Computed Tomography (CT), Positron Emission Positron Emission Tomography PET, PET-CT, or X-Ray imaging. In this embodiment, the present invention will be described based on data from computed tomography (CT). The file format of CT is generally DICOM. Alternatively, other medical image data may be used, and the medical image data may be used to generate a three-dimensional voxel prosthesis. If the radiotherapy system and the treatment thereof disclosed in the present invention can be converted into a cytoplasmic tissue model, It can be applied to the plan generation method.

[0028] Referring to FIG. 3, the radiation therapy system of the present embodiment is preferably a neutron capture therapy system. The system includes a neutron beam irradiation device, a treatment planning module, and a control module. The neutron beam irradiation device 10 includes a neutron generator 11 and a treatment table 12. The neutron generator 11 generates a therapeutic neutron beam N and strikes a patient on a treatment table 12. The treatment planning module 20 uses the neutron generator 11 to irradiate the target area. Based on the parameters of the generated neutron beam N and the medical image data of the irradiated area of ​​the patient, In one embodiment, the treatment plan is generated using a tissue model of the patient in the treatment plan module 20. The tissue model template database 21 is stored, and the treatment planning module 20 Based on the rate database 21, a three-dimensional volume corresponding to the medical image data of the irradiated area is A cell prosthesis tissue model was established and the neutrons generated by the neutron generator 11 were analyzed. Based on the parameters of the child beam N and the 3D voxel prosthesis tissue model, The radiation dose distribution when a patient receives radiation therapy is simulated using a radioisotope simulation program. Simulation calculation and treatment plan generation. Tissue model template database The established model and dosimeter are set in advance, and the differences in the individual experience of the operator such as a doctor are In order to prevent the calculation from being inaccurate, and to define the basic bioinformation of the lattice in the model, The control module 30 controls the treatment planning module 20 to avoid wasting time and energy. Retrieve a treatment plan corresponding to the current patient from the The irradiation of the irradiation device 10 is controlled.

[0029] Referring now to FIG. 4, the method by which the treatment planning module 20 generates a treatment plan according to this embodiment is Specifically, the process includes the following steps S410 to S430.

[0030] In S410, the medical information of the irradiated area is calculated based on the tissue model template database 21. Establish a 3D voxel prosthesis tissue model corresponding to the imaging data.

[0031] In S420, Monte Carlo simulation programs (e.g., MCNP, Mon In the Carlo N Particle Transport Code Dose simulation is performed by defining the beam parameters and sampling different irradiation angles. Perform the calculation.

[0032] In S430, the irradiation angle is suitably selected based on the calculation result to generate a treatment plan. .

[0033] Referring to FIG. 5, in one embodiment, the organizational model template database 21 includes a RO The I template database 211 and the material template database 212 are included. As can be seen, the organizational model template database may also have other settings. The present invention is not particularly limited in this respect. The tissue model template database 21 is used to identify the medical Establishing a 3D voxel prosthetic tissue model corresponding to the image data (Step S) 410 may further include the following steps S610 to S650.

[0034] In S610, medical image data of the irradiated area is read.

[0035] In S620, a 3D medical image voxel model is established. In S630, the ROI template database 211 of the irradiated area is called up, and the irradiated area is Define the boundaries of the ROI set in the site ROI template database 211, or Or read.

[0036] In S640, the material template database 212 for the irradiated portion is called up, and in S63 Gives the voxel-wise material within each ROI defined by 0.

[0037] In S650, a 3D voxel prosthetic tissue model is established.

[0038] ROI refers to the region of interest, which may be important organs such as eyes, liver, bone tissue, brain tissue, etc. The ROI template data may be an important tissue such as a tissue, or may be a tumor cell. The database contains ROs that need to be defined for different irradiated sites (different tumor types). The type of I is set, for example, as shown in Table 1. In one embodiment, BNCT is used for brain tumor treatment. The ROIs that need attention in the process are based on the ROI template database of brain tumors. Create all the ROI types you need to define in advance in the source. For example, Air, Skin, carotid, mucosa, brain tissue in), eyeball, crystalline lens, gland, bone ( Skeleton, Soft tissue, Brain tumor In step S630, the ROI template data of the irradiated region is retrieved. Based on the ROI type set in the database, the treatment planning module 20 will Based on the result, the corresponding ROI boundary is automatically defined or automatically read or manipulated. The authors manually defined all ROI boundaries to obtain a 3D medical image of the irradiated area. Divide the image voxel model into different ROI regions, i.e., divide each voxel unit into the corresponding ROI. The ROI region is divided into two regions. The range of CT values ​​covered by a certain ROI region is wide, and in one embodiment, The planning module 20 then maps the ROI region defined in step S630 to a range of different CT values. For example, brain tissue (Br ain, soft tissue, brain tumor, etc. The ROI type is preset and can be determined according to the individual experience of the operator, such as a doctor. The established 3D prosthetic tissue model is not reliable because the ROIs are inaccurate or incomplete. and prevent inaccurate dose calculations, and save a lot of time and effort in selecting the ROI type. Avoid expending force. Table 1. ROI template database and material template database for brain tumors TIFF2025013976000002.tif199155 TIFF2025013976000003.tif168153

[0039] As shown in FIG. 5, in one embodiment, the material template database 212 includes a tissue type. 21, including the organization type template database 21 21, for each voxel in each ROI, the tissue type (element composition) corresponding to the ROI region is calculated. Step S640 defines the organization type template database 2121. Based on this, the tissue type for each voxel within each ROI defined in step S630 is given. The steps are shown in Table 1. One or more tissue types (elemental composition) corresponding to I are further shown. The data includes information on tissue types, provides more accurate elemental composition, and is based on established geometric models. is matched according to the actual situation reflected by the medical image data. The elemental composition corresponding to different tissue types in OI is preset, and the individual characteristics of the operator, such as the doctor, can be Due to differences in human experience, the same ROI or the same ROI obtained by manually giving or automatically converting Due to differences in elemental composition of tissue types, established 3D prosthetic tissue models and It also provides or modifies the elemental composition within the ROI. This avoids spending a lot of time and energy on converting

[0040] If the radiation therapy system is a boron neutron capture therapy system, the tissue model template Based on the medical image database 21, a 3D voxel corresponding to the medical image data of the irradiated area is Step S410 of establishing a prosthetic tissue model may be performed after step S640. Step S6 providing the voxel-by-voxel tissue boron concentration within each ROI defined in S630 As can be appreciated, S660 may be performed before S640. Using PET etc., the uneven distribution of boron concentration in each tissue and organ can be measured in real time. The boron concentration value for each voxel may be obtained by performing the above-mentioned calculation. The ratio of boron concentration in tumor and tissue to that in blood was calculated. The boron concentration value per voxel may be given to establish uniform boron concentration distribution information. As shown in FIG. 1, in one embodiment, the material template database 212 includes a boron concentration ratio table. The boron concentration ratio template database 2122 is further included. 122 calculates the corresponding tissue boron concentration and blood boron concentration for each voxel in each ROI. Table 1 defines the intensity and ratio of different ROIs in the brain tumor ROI template database. The boron concentration ratios corresponding to the ROI and different tissue types in the same ROI are shown. The concentration of boron-containing drugs in each tissue was estimated by a geometric model labeled with iodine concentration information. This can be clearly understood, and when neutron irradiation simulation is performed, A more realistic reflection of the situation.

[0041] Establish a 3D voxel prosthetic tissue model with tissue type and tissue boron concentration After that, a Monte Carlo simulation program was used to confirm that the patient in BNCT was exposed to neutrons. Simulate the collision trajectory and energy distribution of nuclear particles in 3D space when irradiated with a beam It is possible to simulate the physical dose rate distribution. Calculate the equivalent dose rate distribution based on the physical dose rate distribution, and then calculate the treatment dose based on the dose index. 7, step S420 includes the following steps: Includes tips S710 to S720.

[0042] In S710, the beam parameters ( Define the beam energy, intensity, radius, etc. and sample different irradiation angles. By imaging the 3D voxel prosthesis tissue model, the physical properties of the tissue under different irradiation angles can be analyzed. The dose rate distribution was simulated in three dimensions at each sampling irradiation angle. Each voxel of the voxel prosthesis tissue model is irradiated with a defined beam at a unit time. Simulate the physical dose received per unit.

[0043] When sampling, it is determined to calculate the starting position of the beam and the beam angle. The determination of the starting position and angle in the calculation is done by the forward or backward algorithm. In the forward algorithm, a starting position is determined as an extracorporeal position; It can be calculated by sampling in sequence at fixed angles or distance intervals, and can also be calculated by random sampling. The beam angle can be calculated by the method of sampling. The specific tumor can be set as a vector direction to the tumor center or the deepest point of the tumor. The tumor endpoint position can be adjusted according to the user's needs, and the reverse algorithm In this method, a starting position is determined within the tumor area, and the starting position is determined based on the tumor center, the deepest point, and the tumor mass. or random points within the tumor area, and the beam angle is determined by random sampling. Either sampling or interval sampling may be used.

[0044] When sampling, the beam angle is selected, for example, the beam angle is evaluated, and the evaluation result is Based on this, the beam angle used in subsequent calculations may be selected, or the sampling After the calculation, the beam angle is selected, e.g., the result of the radiation dose distribution or the beam angle The beam angle evaluation method will be described in detail in this specification. No details were provided, it was disclosed on June 16, 2017, and the publication number is CN106853272A The patent application entitled "Method for Evaluating Beam Irradiation Angle" can be referred to. The entire contents of which are incorporated herein.

[0045] As shown in FIG. 3, in one embodiment, the neutron beam irradiation device 10 has a collimator 13. This allows different collimators to be selected for different patients to match the area to be irradiated. Therefore, the beam parameters and irradiation angle irradiated from the collimator exit to the patient are different. When performing Monte Carlo simulations on the S710, the collimator selected In one embodiment, the treatment planning module can be used to simultaneously establish a model of the treatment plan, as shown in FIG. The module 20 may further store a collimator template database 22. The collimator template database 22 stores beam parameters corresponding to different collimators. At least partially defining the data, and performing a Monte Carlo simulation in step S710. When performing an application, the collimator type can be selected manually or read automatically. The collimator template database can be used to select the collimator type. Call the beam parameters.

[0046] In boron neutron capture therapy, the main factor that contributes to the dose has four parts: do.

[0047] 1) Boron dose D B Dose is the amount of boron-containing drug in the tissue or tumor that is irradiated with neutrons. 10 B(n, α) 7 High linear energy transfer α produced by generating a Li neutron capture reaction, 7 It comes from Li particles.

[0048] 2) Fast neutron dose D f : Mainly produced by elastic scattering of epithermal and fast neutrons with hydrogen This comes from the recoil protons produced.

[0049] 3) Thermal neutron dose D th : The dose is mainly 14 N(n,p) 14Generated by C action It comes from a proton and a recoil carbon ion.

[0050] 4) Photon dose D γ : Neutrons interact with the shielding structure to produce a capture reaction with human tissue. and photons induced by the neutrons, the latter being mainly thermal neutrons. 1 H(n,γ) 2 Generates H reaction The photon produced is 2.22 MeV.

[0051] In one embodiment, in step S710, the physical dose received per unit time is calculated using Monte Carlo method. per unit time obtained by simulating with the Carlo simulation program Boron dose (D B ), fast neutron dose (D f ), thermal neutron dose (D th ) and photon dose (D γ ).

[0052] In the S720, equivalent lines at different irradiation angles of a 3D voxel prosthetic tissue model Calculate the dose rate distribution.

[0053] In boron neutron capture therapy, the biological effects of photons and neutrons are different, so The relative biological effectiveness of different tissues for neutron, thermal neutron and photon doses ( Relative biological effectiveness (RBE) By calculating the equivalent dose, the boron dose is calculated as For α, 7 The range of Li particles is short, and damage is generally limited by the boron neutron capture effect. The ability of different cell types to absorb boron-containing drugs varies. Therefore, the distribution of boron concentration in the body becomes uneven, and this line is used to calculate the equivalent dose. The amount of compound biological effect in each tissue was activeness, CBE) and boron concentration in different tissues (step S660 (defined as 1), i.e., the voxel-based equivalent dose rate D is calculated using Eq. And calculate, D(Gy)=CBE(1 / ppm)×B con (ppm) x D B (Gy)+RBE f ×D f (Gy)+RBE th ×D th (Gy)+RBE γ ×D γ (Gy) (Equation 1) where CBE is the compound biological effect of a unit concentration of a boron-containing drug, and B con is the tissue boron concentration and RBE f is the relative biological effectiveness of fast neutrons, and RB E th is the relative biological effectiveness of thermal neutrons, RBE γ is the relative biological effectiveness of photons The result is.

[0054] As shown in FIG. 5, in one embodiment, the material template database 212 includes a biological The effect template database 2123 further includes a biological effect template database 2123 for determining whether the beam is effective for different tissues. Because biological effects vary, the biological effect template database is Define the biological effect of the treatment beam on the tissue corresponding to the ROI region for each unit. Step S640 calls the biological effect template database for the irradiated area. Based on the biological effect template database, each R defined in S630 The method further includes providing a biological effect value for each voxel in the OI. In an embodiment in which the system is a boron neutron capture therapy system, the biological effect template data The base 2123 calculates, for each voxel in each ROI, a CBE corresponding to the ROI region. , R.B.E. f , R.B.E. th , and RBE γ Table 1 defines the ROI template for brain tumors. Different ROIs in the data database and different tissue types in the same ROI CBE, RBE f , R.B.E. th , and RBE γ where the biological effect of photons is The standard is RBE γ is 1. The voxel-wise Providing a biological effect value is the voxel-wise CB within each ROI defined in S630. E., R.B.E. f , R.B.E. th , and RBE γ The process of giving CBE involves: 10 and manually selecting the type of B-containing drug, the different drug types being , which correspond to different CBEs. As an example, the CBEs in Table 1 are 10 Contains B As can be seen, in step S720 a biological effect value is provided. A biological sample corresponding to each ROI and the different tissue types in the ROI may be The clinical effect data is preset, and the results may vary depending on the individual experience of the operator, such as a doctor. Due to differences in biological effect data for the same ROI or tissue type, established 3D Prevents inaccurate prosthetic tissue model and dose calculations, and prevents inaccurate calculations within the ROI. It avoids the expenditure of a great deal of time and energy on providing biological effect data.

[0055] In step S430, a mathematical calculation is performed based on the equivalent dose rate distribution calculated in S720. Combined with a statistical algorithm, different treatment plan proposals (irradiation angles and corresponding irradiation times) are For example, one of the ROI regions may be selected as a target. The ROI region is selected, and the maximum dose, average dose, or prescription dose of the ROI region is set as a constraint, and the sampling is performed. The irradiation time corresponding to the sampled irradiation angle is calculated, and the sampled irradiation is Obtain equivalent dose distribution of 3D voxel prosthesis tissue model at different angles and then linearize Dose-volume histograms (DVH), isodose curves, dose tables, etc. are used to determine the dose distribution for different irradiation angles and The corresponding irradiation time was simulated using a 3D voxel prosthetic tissue model. The equivalent dose distribution obtained by the above is evaluated or suitably selected, and further, the above-mentioned irradiation angle evaluation is performed. By doing so, doctors and other operators can select treatment plan proposals that better meet their needs. As can be seen, at least two illumination angles can be obtained by an optimization algorithm or the like. You can choose the number of degrees to sequentially irradiate the patient, manually set the specific number of irradiation angles, or may be acquired automatically by algorithms or using intensity modulated rotational imaging. In addition, the sampling of illumination angles may be performed on the same or opposite sides of the patient.

[0056] As can be appreciated, the tissue model template database is based on the structure of the embodiments described herein. For example, the structure may include, but is not limited to, an ROI template database, a tissue type template database, etc. database, boron concentration ratio template database, and biological effect template database. In the process of developing a treatment plan, The ROI templates for different irradiation sites were set in the extracted tissue model template database. type, elemental composition in each voxel in each ROI, boron concentration ratio in each voxel in each ROI , and voxel-wise biological effect values ​​within each ROI can be manually corrected. As can be seen, the above formula 1 and the dose calculation, evaluation, and preferred Some simple transformations of such selection methods would still fall within the scope of the present invention.

[0057] As can be appreciated, the present invention further relates to the use of other known radiation therapies such as proton, heavy ion, x-ray or gamma radiation therapy. Other areas of radiation therapy that can be simulated with Monte Carlo software known to those in the art In this case, the neutron beam irradiation device can be applied to other radiation beam irradiation devices. The present invention is also applicable to other diseases that can be treated with radiation, such as Alzheimer's disease and rheumatoid arthritis. The present invention may also be applied to other diseases, in which case the tumor cells are other diseased tissues and the patient is a patient of other diseases. It may be an irradiating body.

[0058] The above describes exemplary specific embodiments of the present invention, and is intended to help those skilled in the art to understand the present invention. However, it is apparent that the present invention is not limited in scope to specific embodiments, and those skilled in the art will readily appreciate that the present invention is not limited in scope to specific embodiments. It is to be understood that various modifications are within the spirit and spirit of the invention as defined and determined by the appended claims. If within the scope of the present invention, these variations are obvious and therefore all fall within the scope of the present invention. is located.

Claims

1. a beam irradiation device that generates a therapeutic beam and irradiates the therapeutic beam onto an irradiated body to form an irradiated area; A tissue model template database of the irradiated object is stored, and the tissue model template A plate database, medical image data of the irradiated area, and the beam irradiation device Based on the parameters of the treatment beam generated by the above method, a dose simulation calculation is performed. a treatment planning module for generating a treatment plan; Retrieving the treatment plan corresponding to the irradiated object from the treatment planning module; A control module controls the beam irradiation device so as to irradiate the subject according to the treatment plan. and a radiation therapy module.

2. The tissue model template database includes a ROI template database and a material a template database, the ROI being a region of interest, The rate database includes the ROI types that need to be defined for the different irradiated regions. The material template database is set to a tissue type template database. the tissue type template database includes a voxel-by-voxel database within each of the ROIs; 2. The radiation therapy method according to claim 1, wherein a corresponding tissue type is defined for each of the following: system.

3. The treatment planning module includes the ROI template database and the tissue type. Based on a template database, a three-dimensional image corresponding to the medical image data of the irradiated area is Establish an original voxel prosthetic tissue model and determine the parameters of the treatment beam and Based on the three-dimensional voxel prosthesis tissue model, a Monte Carlo simulation was performed. A physical dose rate distribution when the treatment beam is irradiated to the irradiation site by the program. The radiation therapy system of claim 2 , further comprising a fabric simulation.

4. The material template database includes a biological effect template database. , the biological effect template database is, for each voxel in each ROI, and defining corresponding biological effect data, the treatment planning module performing the simulation. The physical dose rate distribution and the biological properties of the 3D voxel prosthetic tissue model are Based on the effect data, an equivalent dose rate when the treatment beam is irradiated to the irradiated area is calculated. The radiation therapy system according to claim 3, characterized in that the distribution is calculated.

5. The radiation therapy system is a boron neutron capture therapy system, and the treatment planning module The module defines a corresponding boron concentration for each voxel in each ROI, The three-dimensional voxel prosthesis tissue model was generated using a 3D Carlo simulation program. Boron dose per unit time (D Ｂ ), fast neutron dose (D ｆ ), thermal neutron dose (D ｔｈ ) and photon dose (D γ 4. The method according to claim 3, further comprising the steps of: Radiation therapy system.

6. The material template database further includes a boron concentration ratio template database. The boron concentration ratio template database is stored in each of the ROIs for each voxel. The ratio of the corresponding tissue boron concentration to the blood boron concentration is defined as The radiation therapy system of claim 5.

7. The material template database includes a biological effect template database. , the biological effect template database is, for each voxel in each ROI, The corresponding CBE and RBE ｆ , R.B.E. ｔｈ , and RBE γ and using Equation 1, Calculate the equivalent dose rate D of the three-dimensional voxel prosthetic tissue model; D(Gy)=CBE(1 / ppm)×B ｃｏｎ (ppm)×D Ｂ (Gy)+RBE ｆ ×D ｆ (Gy) + RBE ｔｈ × D ｔｈ (Gy) + RBE γ × D γ (Gy) (Equation 1) where CBE is the compound biological effect of a unit concentration of a boron-containing drug, and B ｃｏｎ is the tissue boron concentration, RBE ｆ is the relative biological effectiveness of fast neutrons, RB E ｔｈ is the relative biological effectiveness of thermal neutrons, RBE γ is the relative biological effectiveness of photons The radiotherapy system according to claim 5 ,

8. The treatment planning module samples different irradiation angles and performs simulation calculations. and selecting at least one irradiation angle based on the equivalent dose rate distribution. The radiotherapy system according to claim 4 or 7,

9. The beam irradiation device further includes a collimator, and a collimator is provided in the treatment planning module. A collimator template database is stored, the collimator template database comprising: At least partially defining parameters of the treatment beam corresponding to different collimators. The radiation therapy system according to claim 1 .

10. Based on a tissue model template database, it corresponds to medical image data of the irradiated area establishing a three-dimensional voxel prosthetic tissue model; Define the beam parameters in the Monte Carlo simulation program and perform different A step of performing a dose simulation calculation by sampling the irradiation angle; and generating a treatment plan by suitably selecting an irradiation angle based on the calculation result.

16. A method for generating a treatment plan for a radiation therapy system, comprising:

11. The tissue model template database includes a ROI template database and a tissue model template database. The ROI refers to a region of interest, and the tissue model includes a tissue type template database. Based on the digital template database, the 3D image data corresponding to the irradiated area is Establishing an ex-voxel prosthetic tissue model includes: reading medical image data of the irradiated area; Establishing a three-dimensional medical image voxel model; A ROI template database of the irradiated area is called up, and the ROI of the irradiated area is Step 1: Define or read the boundaries of the ROI set in the template database. Top and A tissue type template database of the irradiated area is called up, and a tissue type template database of the irradiated area is called up. providing a voxel-wise tissue type; providing a voxel-by-voxel tissue boron concentration within each said ROI; and establishing the three-dimensional voxel prosthesis tissue model. The method for generating a treatment plan according to claim 10 .

12. The tissue model template database is a boron concentration ratio template database Based on a boron concentration ratio template database of the irradiated portion, each of the R By providing the ratio of tissue boron concentration to blood boron concentration for each voxel in the OI, The method according to claim 11, characterized in that it provides tissue boron concentration on a voxel-by-voxel basis within the ROI. The treatment plan generation method described herein.

13. Define beam parameters in the Monte Carlo simulation program, and The step of performing a dose simulation calculation by sampling irradiation angles 、 At the sampled irradiation angles, each voxel of the three-dimensional voxel prosthetic tissue model is The boron dose (D) received per unit time in a beam irradiation with a defined xel unit. Ｂ ), high Fast neutron dose (D ｆ ), thermal neutron dose (D ｔｈ ) and photon dose (D γ ), including physical lines simulating the amount of Definition of each voxel of the three-dimensional voxel prosthetic tissue model using Equation 1: and calculating an equivalent dose rate D per unit time at the determined beam irradiation, D(Gy)=CBE(1 / ppm)×B ｃｏｎ (ppm)×D Ｂ (Gy)+RBE ｆ ×D ｆ (Gy) + RBE ｔｈ × D ｔｈ (Gy) + RBE γ × D γ (Gy) (Equation 1) where CBE is the compound biological effect of a unit concentration of a boron-containing drug, and B ｃｏｎ is the tissue boron concentration, RBE ｆ is the relative biological effectiveness of fast neutrons, RB E ｔｈ is the relative biological effectiveness of thermal neutrons, RBE γ is the relative biological effectiveness of photons and the tissue model template database is a biological effect template database. and based on the biological effect template database of the irradiated area, Voxel-wise CBE and RBE in each ROI ｆ , R.B.E. ｔｈ , and RBE γ Give The method for generating a treatment plan according to claim 11 .

14. Distribution of the equivalent dose rate D calculated by simulating sampling different irradiation angles and selecting at least one illumination angle based on The method for generating a treatment plan according to claim 13 .

15. The radiation therapy system further includes a collimator. In the program, different collimators are selected based on the collimator template database. The treatment according to claim 10, characterized in that the beam parameters are defined as corresponding to Plan generation method.

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