Neutron irradiation positioning parameter determination method, electronic device and storage medium

Abstract

The present invention relates to the field of parameter positioning technology, and specifically provides a method for determining neutron irradiation positioning parameters, an electronic device, and a storage medium. The method comprises: determining an initial irradiation angle and an initial source-skin distance based on the positional relationship between organ tissue and tumor target area in a CT image and the interference relationship between the outer contour of the skin and the treatment head; then constructing a dose-depth curve library based on the reaction characteristics of neutrons and matter; and determining a simulated dose of the target area based on the CT image and the dose-depth curve library. The optimal neutron irradiation positioning parameters are determined by comparing the simulated irradiation time and the ideal dose of the tumor target area under multiple angles. The present invention takes into account the urgent need to reduce the irradiation dose of organs at risk as much as possible and to increase the irradiation dose of tumor tissue as much as possible. The optimal irradiation positioning scheme is obtained through iterative calculation and evaluation under different irradiation angles, saving the time for the initial formulation of the neutron irradiation plan.

Description

Technical Field

[0001] The present invention relates to the technical field of parameter positioning, and specifically provides a neutron irradiation positioning parameter determination method, electronic equipment and storage medium. Background Art

[0002] Neutron capture therapy is a superior cancer treatment option compared to traditional radiation. Boron Neutron Capture Therapy (BNCT), for example, is an advanced radiotherapy method that uses high-energy particles produced by the reaction of boron-10 isotopes with neutrons to precisely kill tumor cells. Neutron therapy planning is a complex and sophisticated process. Within the treatment planning system, physicists often plan the neutron beam's path and range based on the tumor's location, size, shape, and the location of surrounding vital organs. Because each patient's tumor and physical condition are unique, treatment plans must be tailored to their specific circumstances.

[0003] Neutron therapy is different from photon radiotherapy. Neutron therapy is generally a fixed-beam therapy. Since the irradiation angle of the treatment head itself is limited, it requires high flexibility in patient positioning. In addition, the physical process of particle transport in neutron therapy is more complex and the dose composition is more diverse than that of photon radiotherapy, making the full-space dose calculation based on CT images very time-consuming. A single calculation often takes several hours. Therefore, before dose calculation, it is necessary to reasonably plan the neutron irradiation path and provide relatively reasonable incident angles and distances to avoid uncertainties caused by manual settings as much as possible.

[0004] Traditional methods mainly rely on manual experience to set neutron irradiation positioning parameters (incident angle and source-skin distance), and mainly set positioning parameters based on the relative position of the tumor and the organ at risk. However, due to the complex structure of each patient's tissues, the elemental composition of each tissue, the complex biological effects of each tissue, and the relative biological effects of each element are all different, it is often difficult to obtain better positioning parameters through manual setting.

[0005] Therefore, it is necessary to propose a method for determining neutron irradiation positioning parameters that can overcome the lack of traditional manual experience. Summary of the Invention

[0006] In order to overcome the above-mentioned defects, the present invention proposes a method for determining neutron irradiation positioning parameters, which solves the technical problems of traditional reliance on manual experience for parameter setting and inability to achieve automatic parameter optimization.

[0007] In a first aspect, the present invention provides a method for determining neutron irradiation positioning parameters, the method comprising:

[0008] Step S1: Determine the initial irradiation angle and initial source-skin distance based on the positional relationship between the organ tissue and the tumor target area in the CT image and the interference relationship between the skin outer contour and the treatment head;

[0009] Step S2: determining an irradiation parameter set based on the initial irradiation angle, the initial source-skin distance, and the interference relationship, wherein the irradiation parameter set includes multiple sets of one-to-one corresponding irradiation angles and source-skin distances;

[0010] Step S3: Traversing all irradiation angles in the irradiation parameter set, obtaining the ideal dose of the tumor target area at each irradiation angle by performing a preset operation to form an ideal dose set for the tumor target area, and determining the irradiation angle and source-skin distance corresponding to the maximum dose value in the ideal dose set for the tumor target area as the final neutron irradiation positioning parameters;

[0011] The preset operation includes: selecting a set of one-to-one corresponding irradiation angles and source-skin distances from the irradiation parameter set as the current irradiation angle and the current source-skin distance, determining a simulated dose per unit time based on the CT image, the current source-skin distance and a pre-constructed library of dose depth curves for different tissues, determining a shortest simulated irradiation time based on the simulated dose per unit time and a preset prescription dose threshold, and calculating an ideal dose of the tumor target area at the current irradiation angle based on the shortest simulated irradiation time and the simulated dose per unit time.

[0012] In some embodiments, determining the initial irradiation angle and the initial source-skin distance in step S1 based on the positional relationship between the organ tissue and the tumor target area in the CT image and the interference relationship between the skin outer contour and the treatment head includes:

[0013] Step 11: extracting the coordinates of the contour points of the tumor and each organ at risk on each CT layer of the CT image;

[0014] Step 12: determining the center of gravity of the tumor based on the coordinates of the contour points, and traversing all points of the skin outer contour on each layer of CT layer layer by layer based on the center of gravity of the tumor to determine the nearest incident point;

[0015] Step 13: Determine the initial value of the irradiation angle based on the tumor center of gravity and the incident point, and calculate the distance from the beam port center to the skin based on the interference relationship between the skin outer contour and the treatment head and the safe distance between the treatment head and the patient, and record it as the initial value of the source-skin distance;

[0016] Step 14: Determine an initial illumination angle and an initial source-skin distance based on the initial value of the illumination angle, the initial value of the source-skin distance, and the interference relationship.

[0017] Furthermore, in step 14, determining the initial illumination angle and the initial source-skin distance based on the initial value of the illumination angle, the initial value of the source-skin distance, and the interference relationship includes:

[0018] Step a1: determining whether interference occurs when the illumination angle is taken as the initial value based on the interference relationship between the skin outer contour and the treatment head; if so, updating the illumination angle according to a preset angle step and executing step a2; otherwise, determining the initial illumination angle and the initial source-skin distance based on the initial value of the illumination angle and the initial value of the source-skin distance;

[0019] Step a2: determining whether interference occurs at the updated illumination angle, if so, executing step a3; otherwise, determining the initial illumination angle and the initial source-skin distance according to the updated illumination angle and the initial value of the source-skin distance;

[0020] Step a3: Determine whether the updated illumination angle reaches the limit, if yes, execute step a4, otherwise update the illumination angle according to the preset angle step and execute step a2;

[0021] Step a4: adjusting the illumination angle to the initial value of the illumination angle, and updating the source-skin distance according to a preset distance step size based on the initial value of the source-skin distance;

[0022] Step a5: judging whether interference occurs based on the updated source-skin distance, and if so, executing step a6; otherwise, determining the initial illumination angle and the initial source-skin distance based on the initial value of the illumination angle and the updated source-skin distance;

[0023] Step a6: Determine whether the updated source-skin distance reaches a preset source-skin distance threshold. If so, prompt positioning failure. Otherwise, update the source-skin distance according to the preset distance step and execute step a5.

[0024] In some embodiments, determining the irradiation parameter set based on the initial irradiation angle, the initial source-skin distance, and the interference relationship in step S2 includes:

[0025] Step 21: using the initial irradiation angle as the current irradiation angle and the initial source-skin distance as the current source-skin distance;

[0026] Step 22: Determine whether interference occurs at the current illumination angle based on the interference relationship. If interference occurs, execute step 23; otherwise, execute step 25.

[0027] Step 23: Update the current source-skin distance based on the preset length increment and determine whether interference occurs. If interference occurs, execute step 24; if not, execute step 25.

[0028] Step 24: Determine whether the updated source-skin distance reaches the source-skin distance threshold. If so, the current irradiation angle and the current source-skin distance are not included in the irradiation parameter set, and execute step 25; otherwise, continue to execute step 23;

[0029] Step 25: Counting the current irradiation angle and the current source-skin distance as a set of parameters in a one-to-one correspondence into the irradiation parameter set;

[0030] Step 26: Update the current illumination angle based on the preset angle increment, and return to step 22.

[0031] In some embodiments, the method further includes: constructing a library of dose depth curves for different tissues based on the reaction characteristics of neutrons and matter, wherein the library of dose depth curves for different tissues includes a U-segment hydrogen dose depth curve, a U-segment nitrogen dose depth curve, a U-segment gamma dose depth curve associated with the source-skin distance, and a U-segment boron dose depth curve associated with the source-skin distance and boron concentration, wherein U is a positive integer obtained by dividing according to the CT value.

[0032] In some embodiments, determining the simulated dose per unit time based on the CT image, the current source-skin distance, and a pre-built library of different tissue dose depth curves in step S3 includes:

[0033] Based on the CT image, all pixels along the central axis of the neutron beam from the skin entrance point to the skin exit point at the current irradiation angle are counted, and the CT value, ROI attribute, and different component equivalent factors corresponding to each pixel are obtained, where the different component equivalent factors include boron CBE, hydrogen RBE, nitrogen RBE, and gamma RBE;

[0034] Based on the current source-skin distance, a U-segment hydrogen dose depth curve, a U-segment nitrogen dose depth curve, and a U-segment gamma dose depth curve corresponding to the current source-skin distance are extracted from a pre-built library of different tissue dose depth curves, and a U-segment boron dose depth curve corresponding to the current source-skin distance and boron concentration is extracted;

[0035] Based on the CT value of each pixel and the extracted U-segment hydrogen dose depth curve, the U-segment nitrogen dose depth curve, the U-segment gamma dose depth curve, and the U-segment boron dose depth curve, calculating the boron dose, hydrogen dose, nitrogen dose, and gamma dose of each pixel;

[0036] The simulated dose per unit time is determined based on the ROI attribute of each pixel, the different component equivalent factors, and the corresponding boron dose, hydrogen dose, nitrogen dose, and gamma dose.

[0037] Furthermore, the determining of the simulated dose per unit time based on the ROI attribute of each pixel, the equivalent factors of different components, and the corresponding boron dose, hydrogen dose, nitrogen dose, and gamma dose includes:

[0038] Counting the number of ROIs on the central axis of the neutron beam based on the ROI attribute of each pixel, wherein the ROIs include ROIs for characterizing organs at risk and ROIs for characterizing tumor target areas;

[0039] The simulated dose per unit time of each ROI is calculated based on the different component equivalent factors and the boron dose, hydrogen dose, nitrogen dose and gamma dose.

[0040] In some embodiments, determining the shortest simulated irradiation time based on the simulated dose per unit time and a preset prescription dose threshold in step S3 includes:

[0041] Obtain the prescription dose threshold corresponding to each ROI;

[0042] A plurality of simulated irradiation times are calculated based on the prescribed dose threshold of each ROI and the simulated dose per unit time, and the minimum value is selected as the shortest simulated irradiation time.

[0043] In a second aspect, the present invention provides an electronic device comprising at least one processor and at least one memory, wherein the memory is suitable for storing a plurality of program codes, and the program codes are suitable for being loaded and run by the processor to execute the neutron irradiation positioning parameter determination method described in any one of the technical solutions of the above-mentioned neutron irradiation positioning parameter determination method.

[0044] In a third aspect, the present invention provides a computer-readable storage medium storing a plurality of program codes, wherein the program codes are suitable for being loaded and run by a processor to execute the neutron irradiation positioning parameter determination method described in any one of the technical solutions of the above-mentioned neutron irradiation positioning parameter determination method.

[0045] The above one or more technical solutions of the present invention have at least one or more of the following beneficial effects:

[0046] In the technical solution of the present invention, the initial irradiation angle and initial source-skin distance are first automatically optimized based on the patient's structural differences, anti-collision interference, and irradiation angle limitations. Then, the irradiation parameter set is determined based on the initial irradiation angle, initial source-skin distance, and interference relationship. All irradiation angles in the irradiation parameter set are traversed, and the ideal dose of the tumor target area at each irradiation angle is obtained by performing preset operations to form an ideal dose set of the tumor target area. The irradiation angle and source-skin distance corresponding to the maximum dose value in the ideal dose set of the tumor target area are determined as the final neutron irradiation positioning parameters. The preset operations include determining the simulated dose per unit time based on the CT image, the source-skin distance, and a pre-constructed library of different tissue dose depth curves, determining the shortest simulated irradiation time based on the simulated dose per unit time and a preset prescription dose threshold, and calculating the ideal dose of the tumor target area at each irradiation angle based on the shortest simulated irradiation time and the simulated dose per unit time. The present invention comprehensively considers factors such as patient structural differences, anti-collision interference, and irradiation angle limitations to automatically and rapidly iteratively optimize the initial irradiation angle and source-skin distance that can be implemented for neutron therapy. A dose-depth curve library is established based on the reaction characteristics of neutrons and matter, and a personalized composite dose-depth curve model is constructed based on the source-skin distance, boron concentration, and CT images. Simultaneously, the urgent needs of minimizing the irradiation dose to organs at risk and maximizing the irradiation dose to tumor tissue are considered. The optimal irradiation positioning scheme is obtained through iterative calculation and evaluation at different irradiation angles, which can save time in the initial formulation of the neutron irradiation plan. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The disclosure of the present invention will be more easily understood with reference to the accompanying drawings. Those skilled in the art will readily appreciate that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. Furthermore, similar numbers in the drawings represent similar components, wherein:

[0048] Figure 1 is a schematic flow chart of the main steps of a method for determining neutron irradiation positioning parameters according to one embodiment of the present invention;

[0049] Figure 2 This is a schematic flow chart of main implementation steps for determining an initial irradiation angle and an initial source-skin distance according to an embodiment of the present invention;

[0050] Figure 3 This is a schematic flow chart of the main implementation steps of determining an irradiation parameter set according to an embodiment of the present invention;

[0051] Figure 4 The figure is a flow chart of the main implementation steps for obtaining an ideal dose of a tumor target area under an irradiation angle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0052] Some embodiments of the present invention are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0053] In the description of the present invention, "module" and "processor" may include hardware, software, or a combination of both. A module may include hardware circuitry, various suitable sensors, communication ports, and memory. It may also include software components, such as program code, or a combination of software and hardware. A processor may be a central processing unit, a microprocessor, an image processor, a digital signal processor, or any other suitable processor. A processor has data and / or signal processing capabilities. A processor may be implemented in software, hardware, or a combination of both. Non-transitory computer-readable storage media include any suitable medium capable of storing program code, such as magnetic disks, hard disks, optical disks, flash memory, read-only memory, random access memory, and the like. The term "A and / or B" refers to all possible combinations of A and B, such as only A, only B, or both A and B. The terms "at least one of A or B" or "at least one of A and B" have similar meanings to "A and / or B" and may include only A, only B, or both A and B. The singular forms "one" and "the" may also include the plural forms.

[0054] Here we first explain some terms involved in the present invention.

[0055] CT (Computed Tomography) is a medical imaging technology that uses precise X-ray beams and highly sensitive detectors to scan the human body layer by layer. The data obtained from the scan is processed by a computer to generate high-resolution images of the body's internal cross-section, coronal or sagittal planes. CT images reflect the degree of X-ray absorption by organs and tissues in different grayscales, have high density resolution, and can clearly display soft tissue and bone structures. The CT value is an indicator of the density of a substance, and the CT values ​​of different tissues are different. The "layer" in CT refers to the ability of the CT data acquisition system to obtain images synchronously. Simply put, the "layer" is the number of images that can be obtained synchronously in a CT scan, reflecting the functional parameters of the CT scan.

[0056] Source Skin Distance (SSD): The distance from the center of the radiation source to the irradiation center of the skin.

[0057] CBE (Combined Biological Effectiveness): Combined biological effect.

[0058] RBE (Relative Biological Effectiveness): Relative biological effect.

[0059] ROI (region of interest): region of interest.

[0060] The current neutron therapy planning system software is mainly composed of functional modules such as data import, patient management, alignment and fusion, contouring, plan formulation, evaluation and comparison. Among them, plan formulation is the core of the neutron therapy planning system software. Radiation therapy physicists spend most of their time in the plan formulation process. Based on the neutron therapy planning system software, the present invention designs an automatic optimization method for neutron therapy plan schemes in the plan formulation module. Through source information, material information, location information, target area and endangered organ limit, the patient irradiation path is automatically optimized and generated with one click, and the irradiation time is automatically optimized and evaluated. This can improve the efficiency of users in formulating neutron therapy plans and lower the user threshold.

[0061] The neutron irradiation positioning parameter determination method proposed in the present invention is an automatic optimization method for neutron irradiation positioning parameters, which overcomes the shortcomings of traditional manual experience and can directly provide a better irradiation positioning scheme (irradiation angle and source-skin distance) based on the personalized differences of various parts of the patient, the collision interference between the patient and the treatment head, and the reaction characteristics of neutrons and matter, greatly saving the time of the first formulation of the neutron irradiation plan. The neutron irradiation positioning parameter determination method provided by the present invention is applied to the neutron irradiation plan formulation stage. Specifically, the neutron treatment plan formulation process is improved and innovated based on the geometric characteristics, physical characteristics and tumor / organ limit index requirements of the neutron treatment model. Considering the relative biological effects of different particles and the combined biological effects of different boron drugs, the influence of boron drug concentration changes on the dose results can be calculated, and the equivalent dose of each human tissue in the irradiation area can be calculated with high fidelity. The plan optimization algorithm can quickly provide the optimal irradiation plan, which can reduce the equivalent dose of other normal tissues as much as possible while ensuring the target area dose requirements, and avoid vital organs of the human body, thereby developing an efficient automatic optimization function for neutron treatment plans.

[0062] See attached Figure 1 , Figure 1 FIG. 1 is a flow chart showing the main steps of a method for determining neutron irradiation positioning parameters according to an embodiment of the present invention. Figure 1 As shown, the method for determining neutron irradiation positioning parameters in the embodiment of the present invention mainly includes the following steps S1 to S3.

[0063] Step S1: Determine the initial irradiation angle and initial source-skin distance based on the positional relationship between the organ tissue and the tumor target area in the CT image and the interference relationship between the skin outer contour and the treatment head;

[0064] In this embodiment, the interference relationship between the outer contour of the skin and the treatment head can be specifically determined by an interference relationship judgment model. It should be understood that the interference relationship judgment model can judge whether the outer contour of the skin and the treatment head interfere with each other under the input parameters and output the judgment result. The interference relationship judgment model can be a model or module in the existing technology that can realize anti-collision interference judgment.

[0065] Step S2: determining an irradiation parameter set based on the initial irradiation angle, the initial source-skin distance, and the interference relationship, wherein the irradiation parameter set includes multiple sets of one-to-one corresponding irradiation angles and source-skin distances;

[0066] In this embodiment, based on the initial illumination angle, multiple illumination angles are continuously updated according to preset angle increments, and each obtained illumination angle must meet the interference-free condition. Specifically, each time an illumination angle is updated according to the preset angle increment, a determination is made as to whether interference will occur at that illumination angle based on the interference relationship. If interference is determined to occur, the source-skin distance can be adjusted to ensure that the illumination angle meets the interference-free condition. This allows for obtaining an illumination parameter set consisting of all illumination angles and source-skin distances that meet the condition in a one-to-one correspondence.

[0067] Step S3: Traversing all irradiation angles in the irradiation parameter set, obtaining the ideal dose of the tumor target area at each irradiation angle by performing a preset operation to form an ideal dose set for the tumor target area, and determining the irradiation angle and source-skin distance corresponding to the maximum dose value in the ideal dose set for the tumor target area as the final neutron irradiation positioning parameters;

[0068] In this embodiment, the preset operation includes: selecting a set of one-to-one corresponding irradiation angles and source-skin distances from the irradiation parameter set as the current irradiation angle and the current source-skin distance, determining the simulated dose per unit time based on the CT image, the current source-skin distance and a pre-constructed library of dose depth curves for different tissues, determining the shortest simulated irradiation time based on the simulated dose per unit time and a preset prescription dose threshold, and calculating the ideal dose of the tumor target area at the current irradiation angle based on the shortest simulated irradiation time and the simulated dose per unit time.

[0069] In an embodiment of the present application, the method further includes: constructing a library of dose-depth curves for different tissues based on the reaction characteristics of neutrons and matter, wherein the library of dose-depth curves for different tissues includes a U-segment hydrogen dose-depth curve (e.g., Sh), a U-segment nitrogen dose-depth curve (e.g., Sn), a U-segment gamma dose-depth curve (e.g., Sr) associated with the source-skin distance, and a U-segment boron dose-depth curve (e.g., Sb) associated with the source-skin distance and boron concentration, wherein U is a positive integer obtained by dividing the data according to the CT value. For example, U can be set to a positive integer in the range of 1 to 100.

[0070] Based on the above step S1, Figure 2 FIG. 1 is a flow chart of a specific implementation method for determining an initial irradiation angle and an initial source-skin distance provided in an embodiment of the present application. Figure 2 The process shown mainly includes the following steps 11 to 14.

[0071] Step 11: Extract the coordinates of the contour points of the tumor and each organ at risk on each CT layer of the CT image;

[0072] Step 12: determining the center of gravity of the tumor based on the coordinates of the contour points, and traversing all points of the skin outer contour on each layer of CT layer layer by layer based on the center of gravity of the tumor to determine the nearest incident point;

[0073] Step 13: Determine the initial value of the irradiation angle based on the tumor center of gravity and the incident point, and calculate the distance from the beam port center to the skin based on the interference relationship between the skin outer contour and the treatment head and the safe distance between the treatment head and the patient, and record it as the initial value of the source-skin distance;

[0074] In this embodiment, the safety distance between the treatment head and the patient can be customized according to actual needs, for example, the safety distance can be set to 5 cm.

[0075] Step 14: Determine an initial illumination angle and an initial source-skin distance based on the initial value of the illumination angle, the initial value of the source-skin distance, and the interference relationship.

[0076] In a specific implementation, the above step 14 may specifically include the following steps a1 to a6:

[0077] Step a1: determining whether interference occurs when the illumination angle is taken as the initial value based on the interference relationship between the skin outer contour and the treatment head; if so, updating the illumination angle according to a preset angle step and executing step a2; otherwise, determining the initial illumination angle and the initial source-skin distance based on the initial values ​​of the illumination angle and the initial values ​​of the source-skin distance;

[0078] Exemplarily, the preset angle step may be 1 degree.

[0079] Step a2: determining whether interference occurs at the updated illumination angle, if so, executing step a3; otherwise, determining the initial illumination angle and the initial source-skin distance according to the updated illumination angle and the initial value of the source-skin distance;

[0080] Step a3: Determine whether the updated illumination angle reaches the limit, if yes, execute step a4, otherwise update the illumination angle according to the preset angle step and execute step a2;

[0081] In this embodiment, whether the limit is reached can be determined by determining whether the cumulative updated angle step reaches 360 degrees.

[0082] Step a4: adjusting the illumination angle to the initial value of the illumination angle, and updating the source-skin distance according to a preset distance step size based on the initial value of the source-skin distance;

[0083] Exemplarily, the preset distance step may be set to 1 cm.

[0084] Step a5: judging whether interference occurs based on the updated source-skin distance, and if so, executing step a6; otherwise, determining the initial illumination angle and the initial source-skin distance based on the initial value of the illumination angle and the updated source-skin distance;

[0085] Step a6: Determine whether the updated source-skin distance reaches a preset source-skin distance threshold. If so, prompt positioning failure. Otherwise, update the source-skin distance according to the preset distance step and execute step a5.

[0086] Exemplarily, the preset source-skin distance threshold may be 20 cm.

[0087] Based on the above step S2, Figure 3 FIG. 1 is a flow chart of a specific implementation method of determining an irradiation parameter set provided in an embodiment of the present application. Figure 3 The process shown mainly includes the following steps 21 to 23.

[0088] Step 21: using the initial irradiation angle as the current irradiation angle and the initial source-skin distance as the current source-skin distance;

[0089] Step 22: Determine whether interference occurs at the current illumination angle based on the interference relationship. If interference occurs, execute step 23; otherwise, execute step 25.

[0090] Step 23: Update the current source-skin distance based on the preset length increment and determine whether interference occurs. If interference occurs, execute step 24; if not, execute step 25.

[0091] Step 24: Determine whether the updated source-skin distance reaches the source-skin distance threshold. If so, the current irradiation angle and the current source-skin distance are not included in the irradiation parameter set, and execute step 26; otherwise, continue to execute step 23;

[0092] Step 25: Counting the current irradiation angle and the current source-skin distance as a set of parameters in a one-to-one correspondence into the irradiation parameter set;

[0093] Step 26: Update the current illumination angle based on the preset angle increment, and determine whether the illumination angle has reached the limit. If yes, end; otherwise, return to step 22.

[0094] In this embodiment, the preset angle increments may specifically include a yaw angle of ±X degrees, a roll angle of ±Y degrees, and a pitch angle of ±Z degrees, wherein the values ​​of X, Y, and Z may be customized, and the number of illumination angles in the resulting illumination parameter set is related to the preset angle increments. For example, if 1≤X≤45, 1≤Y≤10, and 1≤Z≤10, the corresponding number of illumination angles in the obtained illumination parameter set is G, and 1≤G≤40131. The maximum value of G is determined by (2*X+1)*(2*Y+1)*(2*Z+1), i.e., in this embodiment, the maximum value of G = (2*45+1)*(2*10+1)*(2*10+1)=91*21*21=40131.

[0095] It is understandable that determining whether the illumination angle has reached the limit in step 26 may specifically be determining whether an angle update within a range of 360 degrees is completed based on a preset angle increment.

[0096] Based on the above step S3, Figure 4 The figure shows a specific implementation process of the preset operation provided by the embodiment of the present application, which specifically includes the following steps 31 to 36. The preset operation specifically includes the following steps: Figure 4 Steps 31 to 34 shown in FIG. 3 , wherein the specific implementation of determining the shortest simulated irradiation time based on the simulated dose within the unit time and the preset prescription dose threshold in the preset operation is as follows: Figure 4 Step 35 is shown.

[0097] Step 31: Based on the CT image, all pixels along the central axis of the neutron beam from the skin entrance point to the skin exit point at the current irradiation angle are counted, and the CT value, ROI attribute, and different component equivalent factors corresponding to each pixel are obtained, where the different component equivalent factors include boron CBE, hydrogen RBE, nitrogen RBE, and gamma RBE;

[0098] It is understandable that each pixel has a unique ROI attribute. For example, the ROI attribute may be used to indicate that the location of the pixel is an organ at risk region, or to indicate that the location of the pixel is a tumor target region.

[0099] Exemplarily, the boron CBE can be denoted as Bj(CBE), the hydrogen RBE can be denoted as Hj(RBE), the nitrogen RBE can be denoted as Nj(RBE), and the gamma RBE can be denoted as Rj(RBE), where j represents the jth pixel, 1≤j≤P, and P represents the number of pixels on the central axis of the neutron beam from the skin incident point to the skin exit point.

[0100] Step 32: extracting a U-segment hydrogen dose depth curve, a U-segment nitrogen dose depth curve, and a U-segment gamma dose depth curve corresponding to the current source-skin distance from a pre-built library of different tissue dose depth curves based on the current source-skin distance, and extracting a U-segment boron dose depth curve corresponding to the current source-skin distance and boron concentration;

[0101] Step 33: Based on the CT value of each pixel and the extracted U-segment hydrogen dose depth curve, the U-segment nitrogen dose depth curve, the U-segment gamma dose depth curve, and the U-segment boron dose depth curve, the boron dose, hydrogen dose, nitrogen dose, and gamma dose of each pixel are calculated;

[0102] For example, the statistical boron dose, hydrogen dose, nitrogen dose and gamma dose of each pixel can be recorded as B(j), H(j), N(j) and R(j), respectively, where j represents the jth pixel.

[0103] Step 34: Determine the simulated dose of the ROI per unit time based on the ROI attributes of each pixel, the different component equivalent factors, and the corresponding boron dose, hydrogen dose, nitrogen dose, and gamma dose.

[0104] In this embodiment, step 34 may specifically include the following steps b1 and b2:

[0105] Step b1: counting the number of ROIs on the central axis of the neutron beam based on the ROI attribute of each pixel, wherein the ROIs include ROIs for representing organs at risk and ROIs for representing tumor target areas;

[0106] In this embodiment, the number of ROIs refers to the number of specific organs at risk and target regions. Each pixel on a line along the central axis of the neutron beam, from the skin entry point to the exit point, belongs to a specific organ. However, multiple pixels may belong to the same organ, meaning one pixel corresponds to one organ. However, one organ generally corresponds to multiple pixels. For example, if the number of pixels on the central axis of the neutron beam is 3n, where n ≥ 1, and the ROI attribute of n pixels indicates that the pixel corresponds to the brain, an organ at risk, and the ROI attribute of n pixels indicates that the pixel corresponds to the eye, an organ at risk, and the ROI attribute of n pixels indicates that the pixel corresponds to the tumor target, then the number of ROIs on the central axis of the neutron beam is 3.

[0107] Step b2: Calculating the simulated dose per unit time for each ROI based on the equivalent factors of the different components and the boron dose, hydrogen dose, nitrogen dose and gamma dose.

[0108] Specifically, in this embodiment, the equivalent factors of different components are Bj(CBE), Hj(RBE), Nj(RBE), and Rj(RBE), and the boron dose, hydrogen dose, nitrogen dose, and gamma dose are B(j), H(j), N(j), and R(j), respectively. The simulated dose value for each pixel can be calculated according to Bj(CBE)*B(j)+Hj(RBE)*H(j)+Nj(RBE)*N(j)+Rj(RBE)*R(j). It will be understood that each ROI is composed of multiple pixels, and the simulated dose per unit time for each ROI can be calculated based on the simulated dose value of each pixel.

[0109] In this embodiment, the simulated dose of the target ROI calculated per unit time is the minimum simulated dose of the target ROI, and the simulated dose of the organ at risk calculated per unit time is the maximum simulated dose of the organ at risk ROI.

[0110] Step 35: Obtain the prescription dose threshold corresponding to each ROI, calculate multiple simulated irradiation times based on the prescription dose threshold of each ROI and the simulated dose of the ROI per unit time, and select the minimum value as the shortest simulated irradiation time.

[0111] Exemplarily, the prescribed dose threshold of each ROI is Vi, then 1≤i≤M, where i represents the i-th ROI, and M is the total number of ROIs on the central axis of the neutron beam counted in the above step b1.

[0112] In this embodiment, the ratio of the prescription dose threshold of each ROI to the simulated dose per unit time is calculated, and the minimum value of the ratio is taken as the shortest simulated irradiation time.

[0113] Step 36: Calculate the ideal dose of the tumor target area at the current irradiation angle based on the shortest simulated irradiation time and the simulated dose of the target area per unit time.

[0114] In this embodiment, the ROI is specifically a specific organ at risk or target area. Therefore, based on the simulated dose of the ROI per unit time, the simulated dose of the target area per unit time can be obtained, and then the ideal dose of the tumor target area under the current irradiation angle can be obtained by multiplying the shortest simulated irradiation time by the simulated dose of the target area per unit time.

[0115] This application comprehensively considers factors such as patient structural differences, anti-collision interference, and irradiation angle limitations to automatically and rapidly iteratively optimize the initial irradiation angle and source-skin distance that can be implemented for neutron therapy. Then, a personalized composite dose depth curve model is constructed based on the depth dose curve library, ROI structure, and equivalent factors to obtain the doses of each component that vary with pixels, namely B(j), H(j), N(j), and R(j). Simultaneously, the urgent needs of reducing the irradiation dose to organs at risk as much as possible and increasing the irradiation dose to tumor tissue as much as possible are considered. Through iterative calculation and evaluation at different irradiation angles, the optimal irradiation positioning plan is obtained, saving the time for the first formulation of the neutron irradiation plan.

[0116] It should be pointed out that although the various steps in the above embodiments are described in a specific order, those skilled in the art will understand that in order to achieve the effects of the present invention, different steps do not have to be performed in such an order. They can be performed simultaneously (in parallel) or in other orders. These changes are within the scope of protection of the present invention.

[0117] It will be understood by those skilled in the art that all or part of the processes in the method for implementing the above embodiment of the present invention may also be completed by instructing the relevant hardware through a computer program. The computer program may be stored in a computer-readable storage medium. When the computer program is executed by a processor, it may implement the steps of each of the above method embodiments. The computer program includes computer program code, which may be in source code form, object code form, executable file, or some intermediate form. The computer-readable storage medium may include: any entity or device, medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory, random access memory, electric carrier signal, telecommunication signal, and software distribution medium, etc., which can carry the computer program code.

[0118] Furthermore, the present invention also provides an electronic device. In one embodiment of the electronic device according to the present invention, the electronic device includes at least one processor and at least one memory. The memory can be configured to store a program for executing the method for determining neutron irradiation positioning parameters according to the above-described method embodiment, and the processor can be configured to execute the program stored in the storage device, including but not limited to the program for executing the method for determining neutron irradiation positioning parameters according to the above-described method embodiment. For ease of illustration, only the portions relevant to the embodiment of the present invention are shown. For specific technical details not disclosed, please refer to the method section of the embodiment of the present invention.

[0119] In the embodiment of the present application, the electronic device may be a control device device formed by various devices. In some possible implementations, the electronic device may include multiple memories and multiple processors. The program for executing the neutron irradiation positioning parameter determination method of the above method embodiment can be divided into multiple subroutines, and each subroutine can be loaded and run by the processor to execute different steps of the neutron irradiation positioning parameter determination method of the above method embodiment. Specifically, each subroutine can be stored in different memories respectively, and each processor can be configured to execute the program in one or more memories to jointly implement the neutron irradiation positioning parameter determination method of the above method embodiment, that is, each processor executes different steps of the neutron irradiation positioning parameter determination method of the above method embodiment respectively to jointly implement the neutron irradiation positioning parameter determination method of the above method embodiment.

[0120] The aforementioned multiple processors may be processors deployed on the same device. For example, the aforementioned electronic device may be a high-performance device composed of multiple processors, and the aforementioned multiple processors may be processors configured on the high-performance device. Furthermore, the aforementioned multiple processors may also be processors deployed on different devices. For example, the aforementioned electronic device may be a server cluster, and the aforementioned multiple processors may be processors on different servers in the server cluster.

[0121] Furthermore, the present invention also provides a computer-readable storage medium. In one embodiment of a computer-readable storage medium according to the present invention, the computer-readable storage medium can be configured to store a program for executing the neutron irradiation positioning parameter determination method of the above-mentioned method embodiment. The program can be loaded and run by a processor to implement the above-mentioned neutron irradiation positioning parameter determination method. For ease of explanation, only the parts related to the embodiment of the present invention are shown. For specific technical details not disclosed, please refer to the method part of the embodiment of the present invention. The computer-readable storage medium can be a storage device formed by various electronic devices. Optionally, the computer-readable storage medium in the embodiment of the present invention is a non-transitory computer-readable storage medium.

[0122] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A method for determining neutron irradiation positioning parameters, characterized in that: The method comprises: Step S1: Determine the initial irradiation angle and initial source-skin distance based on the positional relationship between the organ tissue and the tumor target area in the CT image and the interference relationship between the skin outer contour and the treatment head; Step S2: determining an irradiation parameter set based on the initial irradiation angle, the initial source-skin distance, and the interference relationship, wherein the irradiation parameter set includes multiple sets of one-to-one corresponding irradiation angles and source-skin distances; Step S3: Traversing all irradiation angles in the irradiation parameter set, obtaining the ideal dose of the tumor target area at each irradiation angle by performing a preset operation to form an ideal dose set for the tumor target area, and determining the irradiation angle and source-skin distance corresponding to the maximum dose value in the ideal dose set for the tumor target area as the final neutron irradiation positioning parameters; The preset operation includes: selecting a set of one-to-one corresponding irradiation angles and source-skin distances from the irradiation parameter set as the current irradiation angle and the current source-skin distance, determining a simulated dose per unit time based on the CT image, the current source-skin distance and a pre-constructed library of dose depth curves for different tissues, determining a shortest simulated irradiation time based on the simulated dose per unit time and a preset prescription dose threshold, and calculating an ideal dose of the tumor target area at the current irradiation angle based on the shortest simulated irradiation time and the simulated dose per unit time.

2. The method according to claim 1, characterized in that Determining the initial irradiation angle and the initial source-skin distance based on the positional relationship between the organ tissue and the tumor target area in the CT image and the interference relationship between the skin outer contour and the treatment head in step S1 includes: Step 11: extracting the coordinates of the contour points of the tumor and each organ at risk on each CT layer of the CT image; Step 12: determining the center of gravity of the tumor based on the coordinates of the contour points, and traversing all points of the skin outer contour on each layer of CT layer layer by layer based on the center of gravity of the tumor to determine the nearest incident point; Step 13: Determine the initial value of the irradiation angle based on the tumor center of gravity and the incident point, and calculate the distance from the beam port center to the skin based on the interference relationship between the skin outer contour and the treatment head and the safe distance between the treatment head and the patient, and record it as the initial value of the source-skin distance; Step 14: Determine an initial illumination angle and an initial source-skin distance based on the initial value of the illumination angle, the initial value of the source-skin distance, and the interference relationship.

3. The method according to claim 2, characterized in that Determining the initial illumination angle and the initial source-skin distance based on the initial value of the illumination angle, the initial value of the source-skin distance, and the interference relationship in step 14 includes: Step a1: determining whether interference occurs when the illumination angle is taken as the initial value based on the interference relationship between the skin outer contour and the treatment head; if so, updating the illumination angle according to a preset angle step and executing step a2; otherwise, determining the initial illumination angle and the initial source-skin distance based on the initial value of the illumination angle and the initial value of the source-skin distance; Step a2: determining whether interference occurs at the updated illumination angle, if so, executing step a3; otherwise, determining the initial illumination angle and the initial source-skin distance according to the updated illumination angle and the initial value of the source-skin distance; Step a3: Determine whether the updated illumination angle reaches the limit, if yes, execute step a4, otherwise update the illumination angle according to the preset angle step and execute step a2; Step a4: adjusting the illumination angle to the initial value of the illumination angle, and updating the source-skin distance according to a preset distance step size based on the initial value of the source-skin distance; Step a5: judging whether interference occurs based on the updated source-skin distance, and if so, executing step a6; otherwise, determining the initial illumination angle and the initial source-skin distance based on the initial value of the illumination angle and the updated source-skin distance; Step a6: Determine whether the updated source-skin distance reaches a preset source-skin distance threshold. If so, prompt positioning failure. Otherwise, update the source-skin distance according to the preset distance step and execute step a5.

4. The method according to claim 1, wherein Determining the irradiation parameter set based on the initial irradiation angle, the initial source-skin distance, and the interference relationship in step S2 includes: Step 21: using the initial irradiation angle as the current irradiation angle and the initial source-skin distance as the current source-skin distance; Step 22: Determine whether interference occurs at the current illumination angle based on the interference relationship. If interference occurs, execute step 23; otherwise, execute step 25. Step 23: Update the current source-skin distance based on the preset length increment and determine whether interference occurs. If interference occurs, execute step 24; if not, execute step 25. Step 24: Determine whether the updated source-skin distance reaches the source-skin distance threshold. If so, the current irradiation angle and the current source-skin distance are not included in the irradiation parameter set, and execute step 25; otherwise, continue to execute step 23; Step 25: Counting the current irradiation angle and the current source-skin distance as a set of parameters in a one-to-one correspondence into the irradiation parameter set; Step 26: Update the current illumination angle based on the preset angle increment, and return to step 22.

5. The method according to claim 1, wherein The method further includes: constructing a different tissue dose depth curve library based on the neutron-matter reaction characteristics, wherein the different tissue dose depth curve library includes a U-segment hydrogen dose depth curve, a U-segment nitrogen dose depth curve, a U-segment gamma dose depth curve associated with the source-skin distance, and a U-segment boron dose depth curve associated with the source-skin distance and boron concentration, wherein U is a positive integer obtained by dividing according to the CT value.

6. The method according to claim 5, characterized in that Determining the simulated dose per unit time based on the CT image, the current source-skin distance, and a pre-built library of different tissue dose depth curves in step S3 includes: Based on the CT image, all pixels along the central axis of the neutron beam from the skin entrance point to the skin exit point at the current irradiation angle are counted, and the CT value, ROI attribute, and different component equivalent factors corresponding to each pixel are obtained, where the different component equivalent factors include boron CBE, hydrogen RBE, nitrogen RBE, and gamma RBE; Based on the current source-skin distance, a U-segment hydrogen dose depth curve, a U-segment nitrogen dose depth curve, and a U-segment gamma dose depth curve corresponding to the current source-skin distance are extracted from a pre-built library of different tissue dose depth curves, and a U-segment boron dose depth curve corresponding to the current source-skin distance and boron concentration is extracted; Based on the CT value of each pixel and the extracted U-segment hydrogen dose depth curve, the U-segment nitrogen dose depth curve, the U-segment gamma dose depth curve, and the U-segment boron dose depth curve, calculating the boron dose, hydrogen dose, nitrogen dose, and gamma dose of each pixel; The simulated dose per unit time is determined based on the ROI attribute of each pixel, the different component equivalent factors, and the corresponding boron dose, hydrogen dose, nitrogen dose, and gamma dose.

7. The method according to claim 6, characterized in that The determining of the simulated dose per unit time based on the ROI attribute of each pixel, the equivalent factors of different components, and the corresponding boron dose, hydrogen dose, nitrogen dose, and gamma dose includes: Counting the number of ROIs on the central axis of the neutron beam based on the ROI attribute of each pixel, wherein the ROIs include ROIs for characterizing organs at risk and ROIs for characterizing tumor target areas; The simulated dose per unit time of each ROI is calculated based on the different component equivalent factors and the boron dose, hydrogen dose, nitrogen dose and gamma dose.

8. The method according to claim 1, characterized in that Determining the shortest simulated irradiation time based on the simulated dose within the unit time and the preset prescription dose threshold in step S3 includes: Obtain the prescription dose threshold corresponding to each ROI; A plurality of simulated irradiation times are calculated based on the prescribed dose threshold of each ROI and the simulated dose per unit time, and the minimum value is selected as the shortest simulated irradiation time.

9. An electronic device comprising at least one processor and at least one memory, wherein the memory is adapted to store a plurality of program codes, wherein: The program code is suitable for being loaded and run by the processor to execute the method for determining neutron irradiation positioning parameters according to any one of claims 1 to 8.

10. A computer-readable storage medium storing a plurality of program codes, characterized in that: The program code is suitable for being loaded and run by a processor to execute the method for determining neutron irradiation positioning parameters according to any one of claims 1 to 8.

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