Radiotherapy planning assistance system, radiotherapy planning assistance program, and radiotherapy planning assistance method

Abstract

[Problem] To provide a radiotherapy planning assistance system that can efficiently achieve a dose distribution for a radiotherapy device that is close to the established ideal dose distribution, and that can stabilize the quality of a treatment plan by ensuring that the achieved dose distribution does not vary greatly even when different types of radiation therapy devices are used. [Solution] A radiotherapy planning assistance system comprising: a dose distribution storage unit 21b that stores an ideal radiation dose distribution established on the basis of information about the location and cross-sectional contour of an affected area to be irradiated with radiation; a region-generating processing unit 20c that divides the cross-section into two or more regions for each prescribed dose range on the basis of dose distribution information; and a dose parameter setting unit 30a that, for each region, associates prescribed parameter values ​​for radiation doses suitable for achieving the dose distribution with the radiotherapy device to be used.

Description

Radiation Therapy Planning Support System, Radiation Therapy Planning Support Program, and Radiation Therapy Planning Support Method

[0001] The present invention relates to a radiation therapy planning support system, a radiation therapy planning support program, and a radiation therapy planning support method.

[0002] In general, before irradiating a tumor with radiation using a radiation therapy device, medical staff generally use dedicated software for the radiation therapy device in advance to plan and determine the dose distribution to be irradiated based on information in the patient's body obtained from CT images or the like. Normal tissues usually exist around the tumor to be irradiated with radiation, and there are risk organs (Organs at Risk: OAR) that need to be avoided from radiation irradiation as much as possible. Therefore, the dose distribution plan is carried out so as to give the maximum dose to the target tumor while preventing damage to the OAR.

[0003] Increasing the radiation dose to be irradiated to the target also leads to an increase in the dose to the OAR. Therefore, the dose distribution plan is not easy. Parameters related to radiation irradiation are input using the dedicated planning software for the radiation therapy device, the dose distribution is optimized and calculated, and after confirming the result, the parameters are adjusted and recalculated and reconfirmed repeatedly until finally a distribution that can efficiently give more dose to the target without causing damage to the OAR is determined. A lot of time and effort are required to reach this determination.

[0004] In particular, in recent years, intensity-modulated radiation therapy (IMRT), volumetric-modulated radiation therapy (VMRT), etc. have become popular and their functions have also been enhanced, making it possible to concentrate radiation on the tumor more efficiently and reduce the irradiation to surrounding normal tissues. On the other hand, the work of calculating the dose distribution and determining the optimal dose distribution has become more difficult, and the time required for each calculation by the planning software tends to be longer. Therefore, at present, more time and effort are required until medical staff actually determine the dose distribution considered to be optimal.

[0005] In response to this, the present applicant has already proposed a system that obtains an ideal dose distribution based on target affected area information and learning results pre-trained by predetermined deep learning (Patent Document 1). According to this system, a high-quality ideal dose distribution can be created in a short time using AI.

[0006] However, even if an ideal dose distribution can be created in a short time using AI technology, it is not calculated using the dedicated software of the radiation therapy device actually used. Therefore, when importing and implementing that dose distribution into the device, the calculations become complex, and there are limitations to the device's mechanical operation, making it difficult to directly implement the created ideal dose distribution on the device side. In addition, multiple types of radiation therapy devices are in use, each with different mechanisms and characteristics. Therefore, even if a dose distribution close to the ideal can be achieved with one type of device, it does not necessarily mean that it can be achieved with other types of devices. This has led to the problem that the dose distribution (and consequently the quality of the treatment plan) achieved varies greatly depending on the type of device.

[0007] Japanese Patent Publication No. 2020-178935

[0008] Therefore, in view of the above-mentioned circumstances, the present invention aims to provide a radiation therapy planning support system that can efficiently realize a dose distribution close to the ideal dose distribution created in the radiation therapy device, and that can stabilize the quality of the treatment plan by ensuring that the realized dose distribution does not vary greatly even if the type of radiation therapy device is different.

[0009] In light of the current situation, the inventors conducted thorough research and found that the software specifically designed for radiation therapy devices has an optimization calculation function for calculating the dose distribution by setting the parameters as described above. They then conceived the idea of ​​dividing the created ideal dose distribution into two or more regions for each predetermined dose range and simplifying it into data for each region.

[0010] In other words, by simplifying the data to separate data for multiple regions having predetermined dose ranges, it becomes possible to efficiently realize a dose distribution close to the ideal dose distribution in the radiotherapy device without placing a heavy load on the device. At the same time, we have discovered that even if the type of device is different, by simply setting predetermined parameter values ​​for radiation dose appropriate for each device in each region, it is possible to realize a dose distribution close to the ideal dose distribution without causing large variations between devices, and thus completed the present invention.

[0011] Furthermore, the inventors have found that by dividing the OAR or the surrounding area into predetermined dose ranges that are finer than other areas and setting predetermined parameter values ​​for radiation dose, a dose distribution close to the ideal dose distribution can be achieved with any type of radiation therapy device. They have also found that if the characteristics of each type of radiation therapy device are known, the variation in dose distribution due to differences in type can be further suppressed by changing the way the area is divided for each type.

[0012] In other words, the present invention encompasses the following inventions: (1) A radiation therapy planning support system comprising: a dose distribution storage unit that stores an ideal radiation dose distribution created based on information of the position and cross-sectional contour of the affected area to be irradiated with radiation; a regionization processing unit that divides the cross-section into two or more regions for each predetermined dose range based on the dose distribution information; and a dose parameter setting unit that associates predetermined parameter values ​​for radiation doses suitable for realizing the dose distribution with the radiation therapy device to be used with each region.

[0013] (2) The radiation therapy planning support system according to (1), wherein the dose parameter setting unit includes an input field display unit that displays input fields for predetermined parameter values ​​relating to the radiation dose for each region.

[0014] (3) A radiotherapy planning support system according to (1) or (2), comprising a regionized image display unit that generates and displays contour-like regionized images consisting of the contour of the cross section and the boundaries of the plurality of regions, in which each region is distinguishable from other regions.

[0015] (4) The radiation therapy planning support system according to (1) or (2), wherein the regionization processing unit performs a process to subdivide the portion of an organ at risk (OAR) or its vicinity into a region subdivided into a finer dose range compared to other portions. (5) The radiation therapy planning support system according to (1) or (2), wherein the regionization processing unit has two or more templates with different division methods and performs processing based on the selected template.

[0016] (6) The radiotherapy planning support system according to (1) or (2), wherein the predetermined parameter values ​​for radiation dose include one or more predetermined parameter values ​​for radiation dose among the radiation irradiation volume for each region, the target dose, and the priority compared to other regions.

[0017] (7) A radiotherapy planning support program that causes a computer to function as a regionization processing unit that divides the cross-section into two or more regions for each predetermined dose range based on information of an ideal radiation dose distribution created based on information of the location and cross-sectional contour of the affected area to be irradiated with radiation, and a dose parameter setting unit that associates predetermined parameter values ​​for radiation dose suitable for realizing the dose distribution with the radiotherapy device to be used for each region.

[0018] (8) A radiotherapy planning support method comprising: a computer dividing a cross-section into two or more regions for each predetermined dose range based on information of an ideal radiation dose distribution created based on information of the location and cross-sectional contour of the affected area to be irradiated with radiation; setting predetermined parameter values ​​for radiation dose suitable for realizing the dose distribution with the radiotherapy device to be used for each region; and calculating the optimal dose distribution to be realized with the radiotherapy device to be used based on the predetermined parameter values ​​for radiation dose in each region that have been set.

[0019] (9) A computer-readable storage medium storing a radiotherapy planning support program that causes the computer to function as a regionization processing unit that divides the cross section into two or more regions for each predetermined dose range based on information of an ideal radiation dose distribution created based on information of the location and cross-sectional contour of the affected area to be irradiated with radiation, and a dose parameter setting unit that associates predetermined parameter values ​​for radiation doses suitable for realizing the dose distribution with the radiotherapy device to be used for each region.

[0020] According to the radiotherapy planning support system of the present invention as described above, a dose distribution close to the ideal dose distribution created can be efficiently realized by the radiotherapy device, and even if the type of radiotherapy device is different, there will be no large variation in the realized dose distribution, thereby stabilizing the quality of the treatment plan.

[0021] A block diagram showing the overall outline of a radiotherapy system having a radiotherapy planning support system according to a representative embodiment of the present invention. A block diagram showing the configuration of the support computer of the radiotherapy planning support system. A block diagram showing the configuration of the dose distribution creation unit of the support computer. An explanatory diagram showing the procedure for creating tumor / organ contours, dose distributions, regionized images, and treatment plans in the radiotherapy planning support system. An explanatory diagram showing an input screen for entering specified information. A conceptual diagram explaining regionization processing using a basic template. An explanatory diagram showing a specific example of regionization processing using the template in Figure 6. A conceptual diagram explaining regionization processing using other templates. An explanatory diagram showing a specific example of regionization processing using the template in Figure 8. A conceptual diagram explaining regionization processing using yet another template. An explanatory diagram showing a specific example of regionization processing using the template in Figure 10. A conceptual diagram explaining regionization processing using yet another template. A block diagram showing the configuration of the planning computer of the radiotherapy planning support system. A block diagram showing the configuration of the dose parameter setting unit of the planning computer. An explanatory diagram showing an example of an input field (already entered) for predetermined parameter values ​​related to radiation dose. An explanatory diagram explaining the process of regionizing an ideal dose distribution. A flowchart illustrating the processing procedure using the radiation therapy planning support system.

[0022] Hereinafter, typical embodiments of the present invention will be described in detail with reference to the attached drawings.

[0023] As shown in Figure 1, the radiation therapy planning support system 1 according to this embodiment consists of a support computer 2 and a planning computer 3 dedicated to the radiation therapy device 10. The planning computer 3 can be a conventionally known radiation therapy planning system (TPS) computer that plans and determines the dose distribution to be irradiated by the radiation therapy device 10.

[0024] As shown in Figure 2, the support computer 2 is centered around a processing unit 20 and includes storage means 21, input means 22 such as a pointing device, keyboard, or touch panel, display means 23 such as a display, and a communication control unit 24. The processing unit 20 is mainly composed of a CPU such as a microprocessor and has a storage unit consisting of RAM and ROM (not shown) where programs and processing data that define the procedures for various processing operations are stored. The support computer 2 may be a computer configured specifically for this purpose, or a general-purpose personal computer can be used.

[0025] Functionally, the processing unit 20 includes a contour creation unit 20a that creates the contours of tumors and organs, a dose distribution creation unit 20b that creates the ideal radiation dose distribution desired by medical professionals, a regionization processing unit 20c that divides the cross section into two or more regions divided according to predetermined dose ranges, a regionization image display unit 20d that generates and displays contour-like regionization images consisting of the contour of the cross section and the boundaries of the multiple regions, in which each region is displayed in a way that allows it to be distinguished from other regions, and a region information output unit 20e that outputs information about the two or more regions created by the regionization processing unit 20c (including information about the dose range of each region) and the regionization image. These processing functions are realized by the above program.

[0026] The storage means 21 consists of memory or hard disks inside or outside the computer 2. The contents of some or all of the storage units may be stored in the memory or hard disks of other computers connected to the support computer 2. Specifically, the storage means 21 includes at least a contour information storage unit 21a that stores information on the contours of tumors and organs created by the contour creation unit 20a, a dose distribution storage unit 21b that stores the dose distribution created by the dose distribution creation unit 20b, and a region information storage unit 21c that stores information on the regions divided by the region processing unit 20c.

[0027] The contour creation unit 20a creates contours of tumors and organs based on information indicating the position and contours of multiple cross-sections of the same target area captured by the CT scanner 11, and stores them in the contour information storage unit 21a. Contour creation may be performed by having a medical professional draw contours on the images of each cross-section using an input means 22 such as a mouse, or by automatically recognizing contours using an image recognition mechanism and a machine learning mechanism. Figure 4(a) shows an example of a contour 50 created for cross-section 5A.

[0028] The dose distribution creation unit 20b creates an ideal radiation dose distribution for medical professionals based on the location of the affected area and the information of the cross-sectional contour created by the contour creation unit 20a, and stores it in the dose distribution storage unit 21b. As shown in Figure 3, the dose distribution creation unit 20b has a machine learning mechanism 201, and determines the ideal dose distribution by referring to the learning results of the machine learning mechanism 201. Any method such as deep learning using a neural network can be used for the learning method of the machine learning mechanism 201. Preferably, the dose distribution generation system described in Japanese Patent Application Publication No. 2020-178935 and Japanese Patent Application No. 2024-30369, which have already been filed by the applicant of this application, can be used.

[0029] More specifically, this is deep learning using training data with affected area information, which indicates the location and cross-sectional contour of the affected area, as explanatory variables, and dose distribution information as the objective variable. The ideal dose distribution is generated based on the above information on the location and cross-sectional contour of the affected area, as well as the learning results learned in advance by a predetermined deep learning method, and specified information such as the protocol to be used, the irradiation technique, the name of the radiation therapy device to be used, and the plan policy. Figure 5 shows the input screen 6 in which the specified information is entered. Since this specified information is also entered in the training data, the dose distribution creation unit 20b uses the machine learning mechanism 201 to determine the optimal dose distribution for the specified information.

[0030] A protocol refers to a standardized set of procedures and guidelines followed when performing radiation therapy, including the dose administered to the target, the prescribed volume, the dose limits for normal organs used as indicators for managing side effects, the frequency of treatment, and the duration of treatment. Irradiation techniques include, for example, fixed multi-field IMRT and intensity-modulated rotational irradiation (VMAT).

[0031] A plan policy is a policy that sets priorities for each case, referring to priorities such as dose delivery to tumors and dose reduction to normal organs. For example, in addition to the standard model, which is a standard approach, there are multiple plan policy models that can be selected, such as a PTV-priority model that ensures radiation is delivered by planning target volume (PTV), and an OAR-priority model that further reduces radiation delivery to the OAR.

[0032] Figure 4(b) shows an example of the ideal dose distribution 51 that was created. While this example describes an example of creating a dose distribution using a machine learning mechanism, the dose distribution of the present invention is not limited to those created using a machine learning mechanism; it may be created by other methods. Furthermore, it also includes dose distributions created outside of the support computer 2 and input into the support computer 2.

[0033] The regionization processing unit 20c divides the cross-section into two or more regions for each predetermined dose range based on the dose distribution information created by the dose distribution creation unit 20b, and stores them in the region information storage unit 21c. For example, as shown in Figure 6, the cross-section is divided into three regions with doses of 100%, 50%, and 0% as boundaries: region R1, which is the range of 100% or more; region R2, which is the range of 50% to 100%; and region R3, which is the range of 0% to 50%. Specifically, the cross-section is divided into three regions as shown in Figures 7(a) and (b).

[0034] By simplifying the dose distribution, which is a detailed distribution of doses, into data divided into regions based on predetermined dose ranges such as the region of 100% or more dose, the region of 50-100% dose, and the region of 0-50% dose, it becomes possible to efficiently realize a dose distribution close to the ideal dose distribution on the radiation therapy device without placing a heavy load on the device. Furthermore, even if the type of device is different, a dose distribution close to the ideal dose distribution can be realized without causing large variations between devices. Figure 16 shows an example of the process of dividing the ideal dose distribution into three regions (the region of 0-30% dose, the region of 30-60% dose, and the region of 60-90% dose).

[0035] There are no particular limitations on how many regions are divided into based on the dose range. One or more patterns (regionalization templates) can be set in advance for how these regions are divided. It is preferable to have multiple templates available that are suitable for different protocols, irradiation techniques, radiotherapy devices used, and plan policies selected by medical professionals, as described above.

[0036] As a template for regionalization, in addition to the basic forms (methods of division) exemplified in Figures 6 and 7, it is preferable to have a template that divides the area of ​​an organ at risk (OAR) or its surrounding area (R4), which should be avoided from radiation exposure, into more detailed regions based on predetermined dose ranges compared to the areas of other non-risk organs (R1 to R3). For example, as exemplified in Figures 8 and 9, this would involve dividing the area into four regions: R401 for doses of 75-100%, R402 for doses of 50-75%, R403 for doses of 25-50%, and R404 for doses of 0-25%. This makes it possible to more reliably suppress radiation exposure to organs at risk (OAR). It is preferable that such a template be automatically selected, for example, when the OAR-priority model is selected as the plan policy, or to be selected separately by a medical professional.

[0037] Furthermore, it is also preferable to prepare other templates, as illustrated in Figures 10 and 11, that designate the organ at risk (OAR) and the region (R5) at a predetermined distance from the OAR as special areas for reducing the dose. This makes it possible to further reliably reduce radiation exposure to the organ at risk (OAR).

[0038] Furthermore, as another template, as illustrated in Figure 12, it is also preferable to have a template that separates the region (R6) between planned target volumes (PTVs), where high-dose regions are likely to be connected like a bridge, into a special region independent of the others. This makes it possible to reliably irradiate each PTV with a stronger dose. It is also preferable to further divide such region R6 into multiple regions for each predetermined dose range (for example, three regions: R601 for doses of 40-80%, R602 for doses of 0-40%, and R603 for doses of 40-80%).

[0039] Furthermore, it is also preferable to have a template that divides the region into areas where the planned target volume (PTV) and the area up to a predetermined distance from the PTV are defined as regions with a predetermined dose percentage or higher, and other regions are defined by distances that keep the dose below this level. Such regions may be regions that extend a predetermined distance in a specific direction from the PTV. This makes it easier to, for example, restrict the dose on the organ at risk (OAR) side. Multiple predetermined distances may be set. For example, it may be possible to limit the dose to 60% in the region up to 5 cm from the PTV and to 30% in the region up to 10 cm from the PTV.

[0040] When multiple templates are available for regionization, the regionization processing unit 20c may automatically select a template according to the information specified by the medical professional and perform regionization according to that template, or the medical professional may select one in advance. Two or more templates may also be selected in combination. The regionization processing unit 20c stores the information of the multiple regions created according to the templates in the region information storage unit 21c.

[0041] The regionized image display unit 20d generates contour-like regionized images 4 for the multiple regions created by the regionization processing unit 20c, as shown in Figure 4(c), consisting of the cross-sectional outline and the boundary lines of the multiple regions, with each region displayed in a way that allows it to be distinguished from other regions. These images are displayed on the display means 23 and also stored in the region information storage unit 21c.

[0042] The region information output unit 20e exports the information of the multiple regions created in a format usable by the planning computer 3. If the system is connected to the planning computer 3 online via the communication control unit 24, as in this example, the data may be transmitted online, or it may be output to a storage medium such as a USB drive and input to the planning computer 3.

[0043] As shown in FIG. 13, the planning computer 3 includes, centering around a processing device 30, a storage means 31, an input means 32 such as a pointing device, a keyboard, or a touch panel, a display means 33 such as a display, a communication control section 34, and the like. The processing device 30 is mainly composed of a CPU such as a microprocessor and has a storage section composed of a RAM and a ROM (not shown), in which a program defining the procedure of various processing operations and processing data are stored.

[0044] Functionally, the processing device 30 includes a dose parameter setting section 30a that associates a predetermined parameter value related to the radiation dose for each region, a region image display section 30b that displays the region image, and a treatment plan creation section 30c that creates a treatment plan using the radiation treatment device to be used. Further, the storage means 31 includes at least a region information storage section 31a that stores the information of the imported (input) region and the region image data, and a treatment plan storage section 31b that stores the created treatment plan.

[0045] The dose parameter setting section 30a associates a predetermined parameter value related to the radiation dose suitable for realizing the above-described ideal dose distribution with the radiation treatment device 10 to be used for each region. The predetermined parameter value related to the radiation dose is not particularly limited, but preferably includes at least one of the radiation irradiation volume for each region, the target dose, and the priority compared with other regions. These parameter values are determined in advance as optimal initial values for each protocol, irradiation technique, radiation treatment device name to be used, plan policy, and other information selected by medical staff as described above, and for each template to be used.

[0046] In this example, as shown in FIG. 14, the dose parameter setting unit 30a includes an input field display unit 301 that causes the display means 33 to display an input field for inputting the parameter value for each region using the input means 32, and a medical staff inputs a predetermined parameter value in the displayed input field. FIG. 15 is an example of an input screen 7 consisting of input fields (already input) for predetermined parameter values related to radiation dose. Reference numeral 35a is an input field for inputting a parameter value of the irradiation volume for each region, reference numeral 35b is an input field for inputting a parameter value of the target dose for each region, and reference numeral 35c is an input field for inputting a parameter value of the priority for each region. In the figure, “CTV” described in the “Target” column,... “preDose0 - 30%”... etc. are names assigned to each region of a plurality of cross-sections.

[0047] Instead of being input by a medical staff, such parameter values may be automatically set for each region that has been input and stored (registered) in the support computer 2 in advance together with the above templates, etc. (such as in the region partitioning processing unit 20c, etc.) on the support computer 2 side.

[0048] The region-partitioned image display unit 30b displays the region-partitioned image 4 received from the support computer 2 on the display means 33, and as shown in the lower part of FIG. 16, each region can be identified and displayed. Each region can be displayed corresponding to the region selected in the above input field. When inputting parameters or confirming the input content in each region, the medical staff can input or confirm while looking at the region image displayed for each selected region to know which region each parameter value belongs to.

[0049] Of course, the above-described dose parameter setting unit 30a and region-partitioned image display unit 30b can be provided in the support computer 2 instead of being provided in the planning computer 3, or can be provided in both computers.

[0050] The treatment plan creation unit 30c creates a treatment plan using the radiotherapy device, based on the parameter values ​​set in the dose parameter setting unit 30a, using these values ​​as initial values. In other words, the parameter values ​​set in the dose parameter setting unit 30a are parameters for reproducing the ideal dose distribution created by the support computer 2 through optimization calculations by the dedicated planning computer 3 for the specific radiotherapy device 10, and are created as a plan that can be irradiated by the actual radiotherapy device 10. By transmitting the machine parameters that realize this plan to the radiotherapy device 10, the radiotherapy device 10 becomes ready for irradiation. Figure 4(d) shows an example of a dose distribution 52 created as a treatment plan.

[0051] The treatment plan creation unit 30c can use the functions (optimization calculation software) provided by known radiotherapy planning devices as they are. It is difficult and time-consuming to input the ideal dose distribution directly and have the planning computer 3 calculate it, and it is not possible to create an ideal irradiation plan. However, as in the present invention, by first converting the information into a simple region and then setting the parameter values ​​mentioned above, it is possible to efficiently reproduce the ideal dose distribution (a distribution that hits the tumor in an ideal way and suppresses irradiation to organs at risk in an ideal way), and to operate the ideal plan on the radiotherapy device 10 that will actually be used.

[0052] The following describes the processing procedures performed by the radiation therapy planning support system 1, based on Figure 17.

[0053] First, the contour creation unit 20a of the support computer 2 creates the contours of the tumor and organs based on information indicating the position and contours of multiple cross-sections of the same target affected area captured by the CT scanning device 11, and stores them in the contour information storage unit 21a (S101).

[0054] Next, the medical professional inputs the protocol to be used, the irradiation technique, the name of the radiotherapy device to be used, and the plan policy into the support computer 2 (S102). Here, if the medical professional selects a regionization template to be created by the regionization processing unit 20c described later, it is preferable to select it at this stage.

[0055] Next, the dose distribution creation unit 20b of the support computer 2 creates an ideal radiation dose distribution based on the location of the affected area and the information of the cross-sectional contour created by the contour creation unit 20a, and stores it in the dose distribution storage unit 21b (S103).

[0056] Next, the regionization processing unit 20c of the support computer 2 divides the cross-section into two or more regions for each predetermined dose range based on the created dose distribution information and template, and stores the information of these multiple regions in the region information storage unit 21c (S104).

[0057] Next, the area information output unit 20e of the support computer 2 exports the information of the multiple created areas in a format usable by the planning computer 3, and imports it into the planning computer 3 either online or via a storage medium (S105).

[0058] Next, based on the input from the medical personnel, the dose parameter setting unit 30a of the planning computer 3 associates predetermined parameter values ​​related to radiation dose for each region (S106).

[0059] Next, the treatment plan creation unit 30c of the planning computer 3 creates a treatment plan using the radiotherapy device, based on the parameter values ​​set by the dose parameter setting unit 30a, and using these as initial values ​​(S107). Then, the created treatment plan is transferred to the radiotherapy device 10 (S108).

[0060] Although embodiments of the present invention have been described above, the present invention is not limited in any way to these embodiments, and can of course be implemented in various forms without departing from the spirit of the invention. For example, in the embodiments described above, an example was described in which the radiation therapy planning support system 1 is composed of at least two computers, a support computer 2 and a planning computer 3, but the present invention is not limited in any way to such examples, and it is of course possible to compose it with only one computer (for example, only the support computer 2 or the planning computer 3).

[0061] Even when using a single computer, regardless of the type of radiation therapy device, the same effect can be achieved by first creating or inputting and storing an ideal dose distribution, and then, based on this, providing the aforementioned regionalization processing unit and dose parameter setting unit when creating a treatment plan suitable for the radiation therapy device. This allows the radiation therapy device to efficiently realize a dose distribution close to the created ideal dose distribution, and also stabilizes the quality of the treatment plan.

[0062] 1 Radiation therapy planning support system 2 Support computer 3 Planning computer 4 Regionized image 5A Cross-section 6 Input screen 7 Input screen 10 Radiation therapy device 11 CT scanning device 20 Processing device 20a Contour creation unit 20b Dose distribution creation unit 20c Regionization processing unit 20d Regionized image display unit 20e Region information output unit 21 Storage means 21a Contour information storage unit 21b Dose distribution storage unit 21c Region information storage unit 22 Input means 23 Display means 24 Communication control unit 30 Processing device 30a Dose parameter setting unit 30b Regionized image display unit 30c Treatment plan creation unit 31 Storage means 31a Region information storage unit 31b Treatment plan storage unit 32 Input means 33 Display means 34 Communication control unit 35a, 35b, 35c Input fields 50 Contour 51 Dose distribution 52 Dose distribution 201 Machine learning mechanism 301 Input field display section

Claims

1. A radiation therapy planning support system comprising: a dose distribution storage unit that stores an ideal radiation dose distribution created based on information of the location and cross-sectional contour of the affected area to be irradiated with radiation; a regionization processing unit that divides the cross-section into two or more regions for each predetermined dose range based on the dose distribution information; and a dose parameter setting unit that associates predetermined parameter values ​​for radiation doses suitable for realizing the dose distribution with the radiation therapy device to be used with each region.

2. The radiation therapy planning support system according to claim 1, wherein the dose parameter setting unit includes an input field display unit that displays input fields for predetermined parameter values ​​for each region.

3. A radiotherapy planning support system according to claim 1 or 2, comprising a regionized image display unit that generates and displays a contour-like regionized image consisting of the contour of the cross-section and the boundaries of the plurality of regions, wherein each region is displayed in a manner that allows it to be distinguished from other regions.

4. The radiation therapy planning support system according to claim 1 or 2, wherein the regionization processing unit performs a process to divide the portion of an organ at risk (OAR) or its surrounding area into regions with finer predetermined dose ranges compared to other parts.

5. The radiotherapy planning support system according to claim 1 or 2, wherein the regionization processing unit has two or more regionization templates with different division methods, and performs processing based on the selected template.

6. The radiotherapy planning support system according to claim 1 or 2, wherein the predetermined parameter values ​​relating to the radiation dose include one or more parameter values ​​from among the radiation irradiation volume for each region, the target dose, and the priority compared to other regions.

7. A radiation therapy planning support program that causes a computer to function as a regionization processing unit that divides a cross-section into two or more regions for each predetermined dose range, based on information of an ideal radiation dose distribution created based on information of the location and cross-sectional contour of the affected area to be irradiated with radiation, and as a dose parameter setting unit that associates predetermined parameter values ​​for radiation doses suitable for realizing the dose distribution with the radiation therapy device to be used for each region.

8. A radiotherapy planning support method comprising: a computer dividing a cross-section into two or more regions for each predetermined dose range, based on information of an ideal radiation dose distribution created based on the location and cross-sectional contour of the affected area to be irradiated; setting predetermined parameter values ​​for radiation doses suitable for realizing the dose distribution with the radiotherapy device to be used for each region; and calculating the optimal dose distribution to be realized with the radiotherapy device based on the predetermined parameter values ​​for radiation doses for each region that have been set.

9. A computer-readable storage medium that stores a radiotherapy planning support program that causes the computer to function as a regionization processing unit that divides the cross-section into two or more regions for each predetermined dose range based on information of an ideal radiation dose distribution created based on information of the location and cross-sectional contour of the affected area to be irradiated with radiation, and a dose parameter setting unit that associates predetermined parameter values ​​for radiation doses suitable for realizing the dose distribution with the radiotherapy device to be used for each region.

Images