Methods, devices, electronic equipment and media for reconstructing dose distribution in particle irradiation target areas

Abstract

This disclosure provides a method, apparatus, electronic device, and medium for reconstructing the dose distribution of a particle irradiation target area. The method includes: monitoring the irradiation information of particles on a monitoring plane along the incident path, including beam spot position, beam spot size, and dose corresponding to each position, wherein the particles include particles of various energies; calculating the dose of particles of different energies at different depth planes in the target area based on the particle dose ratio of particles of different energies at different depth planes in the target area to the monitoring plane; calculating the particle dose of each energy particle at each position in the target area at different depth planes based on the particle distribution pattern of each energy particle on the monitoring plane; constructing a planar dose model of the target area at different depth planes based on the particle dose of each energy particle at each position in the target area at different depth planes, and reconstructing a three-dimensional dose model by superimposing the models; and fusing the three-dimensional dose model with a three-dimensional image of the target area to obtain a three-dimensional particle dose distribution model of the target area.

Description

Technical Field

[0001] This disclosure relates to the field of particle therapy, and in particular to a method, apparatus, electronic device, and medium for reconstructing the dose distribution of a particle irradiation target area. Background Technology

[0002] Radiation is a beam of particles or photons with specific energies emitted by various radioactive nuclides or particles such as atoms, electrons, and neutrons during energy exchange. Common types of radiation include X-rays, alpha, beta, gamma rays, and neutron rays. Currently, radiation is widely used in the field of radiotherapy.

[0003] Conventional photon radiotherapy can reconstruct the dose distribution within the target area by statistically analyzing the remaining photon flux after photons penetrate the target area. In radiotherapy, proton and heavy ion beams offer advantages over photon beams. While amorphous silicon electron field imaging (EPID) is well-suited for photon detection, it is virtually impossible for protons and heavy ions to penetrate the target area during proton and heavy ion radiotherapy, rendering EPID ineffective. Therefore, effectively reconstructing the target dose during proton and heavy ion therapy is crucial for practical applications. Summary of the Invention

[0004] In view of the above problems, this disclosure provides a method, apparatus, equipment and medium for reconstructing the dose distribution of a particle irradiation target area.

[0005] According to a first aspect of this disclosure, a method for reconstructing the dose distribution of a particle irradiation target area is provided, comprising: monitoring the irradiation information of particles on a monitoring plane along the incident path, the irradiation information including beam spot position, beam spot size, and initial particle dose corresponding to each position, the particles including particles of various energy levels; calculating the total particle dose of particles of different energy levels at different depth planes in the target area based on the particle dose ratio of particles of different energy levels at different depth planes in the target area to the monitoring plane; calculating the particle dose of each energy level particle at each position in the target area at different depth planes based on the particle distribution pattern of each energy level particle on the monitoring plane; constructing planar dose models of different depth planes in the target area based on the particle dose of each energy level particle at each position in the target area at different depth planes; reconstructing a three-dimensional dose model by superimposing the planar dose models of different depth planes in the target area; and fusing the three-dimensional dose model with a three-dimensional image of the target area to obtain a three-dimensional particle dose distribution model of the target area.

[0006] Optionally, before calculating the dose of different energy particles at different depths in the target area, the method further includes: calculating the product of the initial particle dose of each energy particle and a preset calibration factor to obtain the absolute particle dose of each energy particle, so as to calculate the dose of each energy particle at different depths in the target area based on the absolute particle dose.

[0007] Optionally, the step of calculating the total particle dose of different energy particles at different depths in the target area based on the particle dose ratio of different energy particles at different depths in the target area and on the monitoring plane includes: calculating the particle dose ratio of the energy particle reaching different depths in the target area and on the monitoring plane based on the percentage depth dose curve of the energy particle; and calculating the initial particle dose of the energy particle and the product of the particle dose ratio of the energy particle reaching different depths in the target area and on the monitoring plane to obtain the total particle dose of the energy particle reaching different depths in the target area.

[0008] Optionally, the step of calculating the particle dose of each energy particle at different positions in the target area at different depths based on the particle distribution pattern of each energy particle on the monitoring plane includes the following formula:

[0009]

[0010] Among them, E m Let d represent the m-th energy particle. n The depth within the target area is d. n The nth depth plane, Dose(x, y, d) n ) indicates a depth of d n The particle dose at position (x,y) on the depth plane, Dose(d n E m ) represents the m-th energy particle at a depth of d. n Total particle dose in the depth plane, (x i y i ) represents the position of the beam spot center of the particle on the monitoring plane, σ(d n E m ) represents energy E m A beam of energy particles at a depth of d n The standard deviation of the Gaussian distribution on the depth plane.

[0011] Optionally, the three-dimensional dose model is:

[0012]

[0013] Among them, E m Let d represent the m-th energy particle. n Indicates a depth of dn The nth depth plane, Dose(x, y, d) n ) indicates a depth of d n The particle dose at position (x,y) on the depth plane, Dose(d n E m ) represents the m-th energy particle at a depth of d. n Total particle dose in the depth plane, (x i ,y i ) represents the position of the beam spot center of the particle on the monitoring plane, σ(d n E m ) represents energy E m A beam of energy particles at a depth of d n The standard deviation of the Gaussian distribution on the depth plane, N spot Indicates a depth of d n The total number of points N on the depth plane pdd This indicates the number of types of energy particles.

[0014] Optionally, in the three-dimensional dose model, the positions of the energy particles passing through each of the depth planes are mapped to the positions of the energy particles passing through the monitoring plane, and the formula for the mapping relationship includes:

[0015]

[0016] Where, x j The position of the energy particle passing through the depth plane is represented by x0, the position of the energy particle passing through the monitoring plane is represented by h0, the distance from the source of the energy particle to the monitoring plane is represented by d, the distance between the depth plane and the isocenter of the target area is represented by r, and the virtual original axis distance of the energy particle is represented by r.

[0017] The second aspect of this disclosure provides a particle irradiation target area dose distribution reconstruction device, comprising: a dose and position monitoring module for monitoring the irradiation information of particles on a monitoring plane along the incident path, the irradiation information including beam spot position, beam spot size, and initial particle dose corresponding to each position, the particles including particles of various energy levels; a particle dose calculation module for calculating the total particle dose of particles of different energy levels at different depth planes in the target area based on the particle dose ratio of particles of different energy levels at different depth planes in the target area to the monitoring plane; a particle dose distribution calculation module for calculating the particle dose of each energy particle at each position in the target area at different depth planes based on the particle distribution pattern of each energy particle on the monitoring plane; a particle dose model construction module for constructing planar dose models of different depth planes in the target area based on the particle dose of each energy particle at each position in the target area at different depth planes, and reconstructing a three-dimensional dose model by superimposing the planar dose models of different depth planes in the target area; and a particle three-dimensional distribution model construction module for fusing the three-dimensional dose model with a three-dimensional image of the target area to obtain a three-dimensional particle dose distribution model of the target area.

[0018] A third aspect of this disclosure provides an electronic device comprising: one or more processors; and a storage device for storing one or more programs, wherein, when the one or more programs are executed by the one or more processors, the one or more processors perform the method according to any one aspect.

[0019] A fourth aspect of this disclosure provides a computer-readable storage medium having executable instructions stored thereon, which, when executed by a processor, cause the processor to perform the method according to any one of the second aspects.

[0020] Based on the particle irradiation target area dose distribution reconstruction method, apparatus, electronic equipment, and computer-readable storage medium provided in this disclosure, a three-dimensional dose model is constructed by monitoring the dose at the incident end and performing layered dose back-calculation along the ray path. This three-dimensional dose model is then fused with a three-dimensional image of the target area to obtain a three-dimensional particle dose distribution model of the target area. The three-dimensional particle dose distribution model constructed by this method can retain target area particle dose data, serving as a means of ray particle dose tracing. It can independently measure the gamma transmission rate of protons and heavy ions, reducing the use of third-party equipment and improving verification efficiency. This method can be extended to applications in medical and other fields. Attached Figure Description

[0021] The foregoing contents, as well as other objects, features, and advantages of this disclosure, will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0022] Figure 1 A flowchart illustrating a method for reconstructing the dose distribution of a particle irradiation target area according to an embodiment of the present disclosure is shown schematically.

[0023] Figure 2A An active grid scanning beam delivery system is schematically illustrated.

[0024] Figure 2B A schematic diagram of a particle beam modulation and monitoring device according to an embodiment of the present disclosure is shown.

[0025] Figure 3 A schematic diagram illustrating coordinate calculation according to an embodiment of the present disclosure is shown.

[0026] Figure 4A A schematic diagram illustrating dose reconstruction in a plane perpendicular to the beam direction according to an embodiment of the present disclosure is shown.

[0027] Figure 4B A schematic diagram of the beam direction alignment surface dose according to an embodiment of the present disclosure is shown.

[0028] Figure 5 A schematic diagram illustrating the structural block diagram of a particle irradiation target dose distribution reconstruction apparatus according to an embodiment of the present disclosure; and

[0029] Figure 6 A block diagram schematically illustrates an electronic device suitable for implementing a method for reconstructing the dose distribution of a particle irradiation target region according to an embodiment of the present disclosure. Detailed Implementation

[0030] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0032] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0033] It should be noted that the particle irradiation target area dose distribution reconstruction method provided in this disclosure involves technical fields such as particle therapy, particle application, mathematical modeling and image processing, but is not limited thereto.

[0034] Figure 1 A flowchart illustrating a method for reconstructing the dose distribution of a particle irradiation target area according to an embodiment of the present disclosure is shown.

[0035] like Figure 1 As shown, the particle irradiation target area dose distribution reconstruction method provided in this embodiment includes operations S110 to S150.

[0036] S110 monitors the irradiation information of the particles on the incident path monitoring plane. The irradiation information includes the beam spot position, beam spot size, and the dose corresponding to each position. The particles include particles of various energies.

[0037] S120 calculates the total particle dose of particles of different energies at different depths in the target area based on the particle dose ratio of particles of different energies at different depths in the target area and at the monitoring plane.

[0038] S130, based on the particle distribution pattern of each energy particle on the monitoring plane, calculates the particle dose of each energy particle at various positions in the plane at different depths of the target area.

[0039] S140: Based on the particle dose of each energy particle at different positions in the target area at different depth planes, planar dose models of the target area at different depth planes are constructed respectively. After superimposing the planar dose models of the target area at different depth planes, a three-dimensional dose model in the actual process is reconstructed.

[0040] S150, the three-dimensional dose model is fused with the three-dimensional image of the target area to obtain the three-dimensional particle dose distribution model of the target area, which is the dose distribution model of the actual target area irradiation.

[0041] The particle irradiation target area dose distribution reconstruction method provided in this embodiment abandons the method of collecting dose flux after the radiation penetrates the target area in EPD technology. Instead, it uses a new approach to reconstruct the dose distribution of protons and heavy ions in a uniform target area. Specifically, by monitoring the position, dose, and beam spot size data of the incident particles, and using the percentage depth dose curve, the executed dose is reconstructed in three dimensions throughout the process, so as to monitor the dose distribution in the actual process.

[0042] The particle irradiation target dose distribution reconstruction method of this disclosure will be described in detail below.

[0043] Figure 2A An active grid scanning beam delivery system is illustrated schematically.

[0044] like Figure 2AAs shown, this active grid scanning beam delivery system is an active grid scanning beam delivery system implemented by GSI. Unlike passive beam delivery systems, active beam delivery systems generally do not heavily modulate the pencil beam provided by the accelerator (carbon ion beams require mini-RF modulation to slightly broaden the monoenergetic Bragg peak into a mini-SOBP). This technique divides the irradiated target area into several isoenergetic sections along the beam injection direction. Each isoenergetic section is further divided into several scanning points, where an isoenergetic section means that all scanning points on that section have the same energy. By adjusting the ion beam energy and scanning magnet parameters to control the pencil beam irradiation position, layered point-by-point irradiation of the target area is achieved. The scanning points are accumulated in both the lateral and longitudinal directions to achieve a planned uniform dose distribution, greatly improving the conformity of the target area. Therefore, beam modulation equipment such as multi-leaf gratings, collimators, and compensators are no longer needed, thereby reducing the generation of secondary particles.

[0045] Figure 2B A schematic diagram of a particle beam modulation and monitoring device according to an embodiment of the present disclosure is shown.

[0046] like Figure 2B As shown, in this embodiment, the particle beam modulation and monitoring equipment includes an X-scanning iron, a Y-scanning iron, a MI&IC (Multi-Input Multi ...

[0047] In this embodiment, the dose and position monitoring device can be an ionization chamber. The effective detection area of ​​the ionization chamber is larger than the maximum radiation field. When the ionization chamber is working, it records the initial particle dose MU0 and beam spot size σ at each position in real time. E0 It is stored in layers according to different levels (energy).

[0048] In operation S110, via, as Figure 2B The particle beam modulation and monitoring equipment shown monitors the initial particle dose of the particle beam on the monitoring plane (i.e., the detection surface of the ionization chamber) along the incident path. The particle beam includes a variety of energy particles.

[0049] In this embodiment, after monitoring the initial particle dose of the particle beam, before calculating the dose at different depth planes of the target area, the method further includes S111.

[0050] In operation S111, the product of the initial particle dose for each energy level and a preset calibration factor is calculated to obtain the absolute particle dose for each energy level. Based on this absolute particle dose, the total particle dose for each energy level at different depths within the target area is calculated. The formula is expressed as:

[0051] Dosed0 = MU0 × Calibration Factor

[0052] The calibration factor in the formula is obtained by calibrating the position dose monitoring device. The calibration factor is equal to the dose ratio MU0 measured by the absolute dose ionization chamber. It is a variable value that is measured by the equipment quality control personnel.

[0053] In operation S120, the total particle dose of different energy particles at different depths in the target area is calculated based on the particle dose ratio of different energy particles at different depths in the target area and the monitoring plane. Specifically, this includes operations S121 to S122.

[0054] In operation S121, based on the percentage depth dose curve of the energy particle, the distribution dose of the energy particle at different depth planes in the target area and the monitoring plane is provided, and the particle dose ratio of the energy particle reaching different depth planes in the target area and the monitoring plane is calculated.

[0055] It should be noted that each energy particle has a unique percentage depth dose (PDD) curve. The percentage depth dose curve refers to the ratio of the absorbed dose Dd at a certain depth d along the central axis of the radiation phantom to the absorbed dose D0 at a reference depth d0. It is a physical quantity describing the relative dose distribution at different depths along the central axis of the radiation phantom. Furthermore, the PDD curve for the same energy in the same medium is uniquely invariant; that is, by measuring the dose at any depth along this curve, the dose for the entire curve can be calculated.

[0056]

[0057] D d D0 is the absorbed dose at a point at depth d on the central axis of the ray, and D0 is the absorbed dose at a certain depth 0 on the central axis of the ray.

[0058] In operation S122, the initial particle dose of the energy particles and the product of the ratio of the particle dose at different depths of the target area to the particle dose on the monitoring plane are calculated respectively to obtain the total particle dose of the energy particles at different depths of the target area.

[0059] S130, based on the particle distribution pattern of each energy particle on the monitoring plane, calculates the particle dose of each energy particle at various positions on the plane at different depths in the target area.

[0060] In this embodiment, the formula for calculating the particle dose at various positions of the energy particles at different depths in the target area includes:

[0061]

[0062] Among them, E m Let d represent the m-th energy particle. n The depth within the target area is d. n The nth depth plane, Dose(x, y, d)n ) indicates a depth of d n The particle dose at position (x,y) on the depth plane, Dose(d n E m ) represents the m-th energy particle at a depth of d. n Total particle dose in the depth plane, (x i ,y i ) represents the position of the beam spot center of the particle beam on the monitoring plane, σ(d n E m ) represents energy E m A beam of energy particles at a depth of d n The standard deviation of the Gaussian distribution on the depth plane.

[0063] In operation S140, based on the particle dose of each energy particle at various positions in different depth planes of the target area, planar dose models of different depth planes of the target area are constructed respectively. After superimposing the planar dose models of different depth planes of the target area, a three-dimensional dose model in the actual process is reconstructed.

[0064] The three-dimensional dose calculation model includes:

[0065]

[0066] Among them, E m Let d represent the m-th energy particle. n Indicates a depth of d n The nth depth plane, Dose(x, y, d) n ) indicates a depth of d n The particle dose at position (x,y) on the depth plane, Dose(d n E m ) represents the m-th energy particle at a depth of d. n Total particle dose in the depth plane, (x i ,y i ) represents the position of the beam spot center of the particle beam on the monitoring plane, σ(d n E m ) represents energy E m A beam of energy particles at a depth of d n The standard deviation of the Gaussian distribution on the depth plane, N spot Indicates a depth of d n The total number of points N on the depth plane pdd This indicates the number of types of energy particles.

[0067] Figure 3 A schematic diagram illustrating coordinate calculation according to an embodiment of the present disclosure is shown.

[0068] like Figure 3 As shown, in the three-dimensional dose calculation model, the positions of the particle beam passing through each depth plane of the target area have a mapping relationship with the positions of the particle beam passing through the monitoring plane. The formula for this mapping relationship includes:

[0069]

[0070] Where, x j The position of the particle beam passing through a given depth plane in the target area is represented by x0, the position of the energy particle passing through the monitoring plane is represented by h0, the distance from the energy particle source to the monitoring plane is represented by d, the distance between the depth plane and the isocenter (OIS) of the target area is represented by r, and the virtual original axis distance of the particle beam is represented by r.

[0071] S150, the three-dimensional dose model is fused with the three-dimensional image of the target area to obtain the three-dimensional particle dose distribution model of the target area, which is the dose distribution model of the actual target area irradiation.

[0072] Figure 4A A schematic diagram illustrating dose reconstruction in a plane perpendicular to the beam direction according to an embodiment of the present disclosure is shown. Figure 4B A schematic diagram of the beam direction alignment surface dose according to an embodiment of the present disclosure is shown.

[0073] Essentially, the entire dose reconstruction process is similar to the TPS calculation plan. However, TPC calculates the theoretically required energy layer, particle position distribution on each layer, and number of particles at each position based on the required dose distribution. In contrast, the embodiments disclosed in this disclosure deduce the actual execution data of the isocenter target area position by recording the number of particles and beam spot size at each layer and position on the dose and position monitoring device during the actual process, thereby calculating the dose distribution of the target area during the actual process.

[0074] The three-dimensional particle dose distribution model constructed by the particle irradiation target area dose distribution reconstruction method provided in this disclosure can retain target area particle dose data. As a means of tracing radiation particle dose, it can independently measure the gamma transmission rate of protons and heavy ions, reducing the use of third-party equipment and improving verification efficiency. This method can be extended to medical and other application fields.

[0075] Furthermore, the present disclosure embodiments are feasible for reconstructing the dose during a single detection process. Similarly, the reconstruction and superposition methods provided in the present disclosure embodiments can be extended to multi-angle and multi-field situations.

[0076] Figure 5 A schematic block diagram of a particle irradiation target area dose distribution reconstruction apparatus according to an embodiment of the present disclosure is shown.

[0077] like Figure 5As shown, the particle irradiation target area dose distribution reconstruction device of this disclosure includes: a dose and position monitoring module 510, a particle dose calculation module 520, a particle dose distribution calculation module 530, a particle dose model construction module 540, and a particle three-dimensional distribution model construction module 550.

[0078] The dose and position monitoring module 510 is used to monitor the irradiation information of particles on the monitoring plane along the incident path. The irradiation information includes the beam spot position, beam spot size, and the initial particle dose corresponding to each position. The particles include various energy particles. In one embodiment, the dose and position monitoring module 510 can be used to perform the operation S110 described above, which will not be repeated here.

[0079] The particle dose calculation module 520 is used to calculate the total particle dose of different energy particles at different depths in the target area based on the particle dose ratio of different energy particles at different depths in the target area to the monitoring plane. In one embodiment, the particle dose calculation module 520 can be used to perform the operation S120 described above, which will not be repeated here.

[0080] The particle dose distribution calculation module 530 is used to calculate the particle dose of each energy particle at different positions in the target area at different depths, based on the particle distribution pattern of each energy particle in the monitoring plane. In one embodiment, the particle dose distribution calculation module 530 can be used to perform the operation S130 described above, which will not be repeated here.

[0081] The particle dose model construction module 540 is used to construct planar dose models for different depths of the target area based on the particle dose of each energy particle at various positions in the plane at different depths of the target area. The planar dose models are then superimposed to reconstruct the three-dimensional dose model in the actual process. In one embodiment, the particle dose distribution model reconstruction module 540 can be used to perform the operation S140 described above, which will not be repeated here.

[0082] The particle three-dimensional distribution model construction module 550 is used to fuse the three-dimensional dose model with the three-dimensional image of the target area to obtain a three-dimensional particle dose distribution model of the target area. In one embodiment, the particle three-dimensional distribution model construction module 550 can be used to perform the operation S150 described above, which will not be repeated here.

[0083] According to embodiments of this disclosure, any plurality of modules among the dose and position monitoring module 510, particle dose calculation module 520, particle dose distribution calculation module 530, particle dose model construction module 540, and particle three-dimensional distribution model construction module 550 can be combined into one module, or any one of these modules can be split into multiple modules. Alternatively, at least part of the functionality of one or more of these modules can be combined with at least part of the functionality of other modules and implemented in one module. According to embodiments of this disclosure, at least one of the dose and position monitoring module 510, particle dose calculation module 520, particle dose distribution calculation module 530, particle dose model construction module 540, and particle three-dimensional distribution model construction module 550 can be at least partially implemented as hardware circuitry, such as a field-programmable gate array (FPGA), a programmable logic array (PLA), a system-on-a-chip, a system-on-a-substrate, a system-on-package, an application-specific integrated circuit (ASIC), or any other reasonable means of integrating or packaging the circuitry, or implemented in any one of software, hardware, and firmware methods, or in a suitable combination of any of these methods. Alternatively, at least one of the dose and location monitoring module 510, particle dose calculation module 520, particle dose distribution calculation module 530, particle dose model construction module 540, and particle three-dimensional distribution model construction module 550 can be at least partially implemented as a computer program module, which can perform corresponding functions when the computer program module is run.

[0084] Figure 6 A block diagram schematically illustrates an electronic device suitable for implementing a method for reconstructing the dose distribution of a particle irradiation target region according to an embodiment of the present disclosure.

[0085] like Figure 6 As shown, an electronic device 600 according to an embodiment of this disclosure includes a processor 601, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 602 or a program loaded from a storage portion 608 into a random access memory (RAM) 603. The processor 601 may include, for example, a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or an associated chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 601 may also include onboard memory for caching purposes. The processor 601 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of this disclosure.

[0086] RAM 603 stores various programs and data required for the operation of electronic device 600. Processor 601, ROM 602, and RAM 603 are interconnected via bus 604. Processor 601 performs various operations of the method flow according to embodiments of the present disclosure by executing programs in ROM 602 and / or RAM 603. It should be noted that programs may also be stored in one or more memories other than ROM 602 and RAM 603. Processor 601 may also perform various operations of the method flow according to embodiments of the present disclosure by executing programs stored in said one or more memories.

[0087] According to embodiments of this disclosure, the electronic device 600 may further include an input / output (I / O) interface 605, which is also connected to a bus 604. The electronic device 600 may also include one or more of the following components connected to the I / O interface 605: an input section 606 including a keyboard, mouse, etc.; an output section 607 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN card, modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to the I / O interface 605 as needed. A removable medium 611, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on the drive 610 as needed so that computer programs read from it can be installed into the storage section 608 as needed.

[0088] This disclosure also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiments; or it may exist independently and not assembled into the device / apparatus / system. The computer-readable storage medium carries one or more programs that, when executed, implement the method according to the embodiments of this disclosure.

[0089] According to embodiments of this disclosure, the computer-readable storage medium may be a non-volatile computer-readable storage medium, such as including, but not limited to: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this disclosure, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. For example, according to embodiments of this disclosure, the computer-readable storage medium may include ROM 602 and / or RAM 603 and / or one or more memories other than ROM 602 and RAM 603 described above.

[0090] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0091] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0092] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A method for reconstructing the dose distribution of a particle-irradiated target area, characterized in that, include: The irradiation information of the monitoring plane on the incident path of the monitoring particles includes the beam spot position, beam spot size and the initial particle dose corresponding to each position, and the particles include multiple energy particles; Based on the particle dose ratio of different energy particles at different depths in the target area and on the monitoring plane, the total particle dose of different energy particles at different depths in the target area is calculated. Based on the particle distribution pattern of each energy particle on the monitoring plane, the particle dose of each energy particle at each position in the plane at different depths of the target area is calculated. Based on the particle dose of each energy particle at different positions in the target area at different depth planes, planar dose models of the target area at different depth planes are constructed respectively. After superimposing the planar dose models of the target area at different depth planes, a three-dimensional dose model is reconstructed. The three-dimensional dose model is fused with the three-dimensional image of the target area to obtain a three-dimensional particle dose distribution model of the target area; The calculation of particle dose at various positions in the target area at different depths is based on the particle distribution pattern of each energy particle on the monitoring plane. The calculation formula includes: Among them, E m Let d represent the m-th energy particle. n The depth within the target area is d. n The nth depth plane, Dose(x,y,d) n ) indicates a depth of d n The particle dose at position (x,y) on the depth plane, Dose(d n E m ) represents the m-th energy particle at a depth of d. n The total particle dose in the depth plane, (x i ,y i ) represents the position of the beam spot center of the particle on the monitoring plane, σ(d) n E m ) represents energy E m A beam of energy particles at a depth of d n The standard deviation of the Gaussian distribution on the depth plane.

2. The method according to claim 1, characterized in that, Before calculating the dose of particles with different energies at different depths in the target region, the method further includes: The product of the initial particle dose of each type of energy particle and a preset calibration factor is calculated to obtain the absolute particle dose of each type of energy particle, and the dose of each type of energy particle at different depth planes in the target area is calculated based on the absolute particle dose.

3. The method according to claim 1, characterized in that, The calculation of the total particle dose of different energy particles at different depths within the target area, based on the particle dose ratio of different energy particles at different depths within the target area to the monitoring plane, includes: The particle dose ratio at different depths of the target area and the monitoring plane is calculated based on the percentage depth dose curve of the energy particle. The initial particle dose of the energy particle and the product of the ratio of the particle dose at different depths of the target area to the particle dose on the monitoring plane are calculated to obtain the total particle dose of the energy particle at different depths of the target area.

4. The method according to claim 1, characterized in that, The three-dimensional dose model is as follows: Among them, E m Let d represent the m-th energy particle. n Indicates a depth of d n The nth depth plane, Dose(x,y,d) n ) indicates a depth of d n The particle dose at position (x,y) on the depth plane, Dose(d n E m ) represents the m-th energy particle at a depth of d. n The total particle dose in the depth plane, (x i ,y i ) represents the position of the beam spot center of the particle on the monitoring plane, σ(d) n E m ) represents energy E m A beam of energy particles at a depth of d n The standard deviation N of the Gaussian distribution on the depth plane spot Indicates a depth of d n The total number of points N on the depth plane pdd This indicates the number of types of energy particles.

5. The method according to claim 4, characterized in that, In the three-dimensional dose model, the positions of the energy particles passing through each depth plane are mapped to the positions of the energy particles passing through the monitoring plane. The formula for this mapping relationship includes: Where, x j The position of the energy particle passing through the depth plane is represented by x0, the position of the energy particle passing through the monitoring plane is represented by h0, the distance from the source of the energy particle to the monitoring plane is represented by d, the distance between the depth plane and the isocenter of the target area is represented by r, and the virtual original axis distance of the energy particle is represented by r.

6. A device for reconstructing the dose distribution of a particle irradiation target area, characterized in that, include: The dose and position monitoring module is used to monitor the irradiation information of the particles on the monitoring plane along the incident path. The irradiation information includes the beam spot position, beam spot size, and the initial particle dose corresponding to each position. The particles include various energy particles. The particle dose calculation module is used to calculate the total particle dose of different energy particles at different depths in the target area based on the particle dose ratio of different energy particles at different depths in the target area and the monitoring plane. The particle dose distribution calculation module is used to calculate the particle dose of each energy particle at different positions in the plane at different depths of the target area based on the particle distribution pattern of each energy particle in the monitoring plane. The particle dose model construction module is used to construct planar dose models at different depths of the target area based on the particle dose of each energy particle at various positions in the plane at different depths of the target area. The planar dose models at different depths of the target area are superimposed to reconstruct a three-dimensional dose model. The particle three-dimensional distribution model construction module is used to fuse the three-dimensional dose model with the three-dimensional image of the target area to obtain the three-dimensional particle dose distribution model of the target area; The calculation of particle dose at various positions in the target area at different depths is based on the particle distribution pattern of each energy particle on the monitoring plane. The calculation formula includes: Among them, E m Let d represent the m-th energy particle. n The depth within the target area is d. n The nth depth plane, Dose(x,y,d) n ) indicates a depth of d n The particle dose at position (x,y) on the depth plane, Dose(d n E m ) represents the m-th energy particle at a depth of d. n The total particle dose in the depth plane, (x i ,y i ) represents the position of the beam spot center of the particle on the monitoring plane, σ(d) n E m ) represents energy E m A beam of energy particles at a depth of d n The standard deviation of the Gaussian distribution on the depth plane.

7. An electronic device, comprising: One or more processors; Storage device for storing one or more programs. Wherein, when the one or more programs are executed by the one or more processors, the one or more processors perform the method according to any one of claims 1 to 5.

8. A computer-readable storage medium having executable instructions stored thereon, which, when executed by a processor, cause the processor to perform the method according to any one of claims 1 to 5.

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