WO2022158047A1

WO2022158047A1 - Determination assistance system, radiotherapy system, and determination assistance method for determination assistance system

Info

Publication number: WO2022158047A1
Application number: PCT/JP2021/035051
Authority: WO
Inventors: 徹梅川; 祐介藤井; 貴啓山田
Original assignee: 株式会社日立製作所
Priority date: 2021-01-20
Filing date: 2021-09-24
Publication date: 2022-07-28
Also published as: JP2022111774A

Abstract

The present invention assists in determination and operation during treatment even in a hospital with staff having less experience of adaptive radiotherapy. A determination assistance system 10, 14, 15 accepts an input of determination assistance data comprising a pair of a determination index to be evaluated during radiation therapy and a determination reference value, accepts an input of selection of determination assistance data to be used for each target of the radiation therapy, calculates a determination index value for an image of a predetermined region including the target captured by an imaging device for imaging the predetermined region on the day of treatment, and compares and displays the determination index value and the determination reference value.

Description

Decision support system, radiotherapy system, and decision support method in decision support system

The present invention relates to a decision support system, a radiotherapy system, and a decision support method in a decision support system.

The present invention preferably relates to a radiotherapy system having a function for supporting adaptive treatment decision-making in response to changes in the patient's body structure during treatment.

The purpose of radiation therapy is to irradiate and treat the target within the patient's body with concentrated radiation. Improving the concentration of dose to the target reduces the dose to the organs around the target and reduces side effects.

In radiation therapy, a treatment plan is implemented in which the radiation irradiation method, such as which direction and how much to irradiate, is determined by simulation, and then irradiation is performed over multiple days. Since the days pass between treatment planning and irradiation, structures within the patient's body can change. Due to this structural change, the dose to the target and peripheral organs may vary from day to day even if the same irradiation method is used. In the treatment plan, the radiation dose to the target and surrounding organs is evaluated in anticipation of this change, and the irradiation method is determined. It is generally planned to irradiate an area larger than the target itself, so that the target receives the desired dose regardless of variation.

If it is possible to measure this change in the patient immediately before irradiation and adjust the irradiation method according to the change, it is believed that a dose that is more focused on the target can be achieved. This is called adaptive therapy. This adaptive treatment is called online adaptive treatment, in which the irradiation method is adjusted while the patient is lying on the treatment bed based on the image taken on the day of irradiation. High-precision treatment becomes possible.

In order to execute this online adaptive treatment, it is necessary to grasp the structural change, modify the plan, and verify it while the patient is lying on the treatment bed. Software that can execute each at high speed This requires a skilled operator who can quickly make the decisions that are required at any given time. In order for this online adaptive treatment to be accepted by various hospitals, a mechanism that supports quick decisions and operations during this treatment is necessary.

A method for supporting judgment and operation during treatment is described, for example, in Patent Document 1. Patent Document 1 describes "Automated workflow for adaptive radiation therapy comprising a procedure for obtaining a set of instructions containing information representative of a planned treatment and stepwise generation of a model of a patient using the set of instructions; and a series of automated steps of first and second treatment plan generation for a patient model and a procedure for selecting the appropriate treatment plan for the current treatment session."

U.S. Patent Application Publication No. 2020/0121951

By using the automatic workflow described in Patent Document 1, operations are automatically performed during treatment based on instructions created in advance, enabling prompt treatment. However, even if an automatic operation is performed, it is necessary for specialists to judge whether the result created or selected by automatically set parameters is suitable for treatment and to decide whether to proceed to the next operation. House knowledge is required. Such judgments require specialized knowledge and are difficult for hospitals that do not have experienced staff.

The present invention has been made in view of the above problems, and a judgment support system, a radiotherapy system, and a An object of the present invention is to provide a judgment support method in a judgment support system.

In order to solve the above problems, for example, the configurations described in the claims are adopted.
The present invention includes a plurality of means for solving the above problems. To give one example, a decision support system receives input of decision support data consisting of a set of a decision index and a decision reference value to be evaluated during treatment. Accept, accept selection input of decision support data to be used for each target of radiation therapy, and calculate a decision index value for an image of a predetermined area captured by an imaging device that captures a predetermined area including the target on the day of treatment. Then, the value of the judgment index and the judgment reference value are compared and displayed.

According to the present invention, it is possible to support judgment and operation during treatment even in hospitals with staff who have little experience in adaptive radiation therapy.

1 is a diagram showing a schematic configuration of a radiotherapy system according to Example 1; FIG. 4 is a diagram showing an example of structural change determination support data in the radiotherapy system according to the first embodiment. FIG. FIG. 8 is a diagram showing another example of structural change determination support data in the radiotherapy system according to the first embodiment; FIG. 4 is a diagram showing an example of replanning determination support data in the radiotherapy system according to the first embodiment; 4 is a diagram showing an example of judgment support data for treatment plan evaluation in the radiotherapy system according to Example 1. FIG. 4 is a flow chart showing the operation of the radiotherapy system according to Example 1. FIG. 4 is a flow chart showing the positioning operation of the radiotherapy system according to Example 1. FIG. 4 is a flow chart showing contour creation necessity determination operation of the radiotherapy system according to the first embodiment. 4 is a flow chart showing contour creation/verification operations of the radiotherapy system according to the first embodiment. 4 is a flow chart showing a treatment plan selection operation of the radiotherapy system according to Example 1. FIG. 4 is a flow chart showing treatment plan evaluation operation of the radiotherapy system according to Example 1. FIG. 4 is a flow chart showing radiation irradiation operation of the radiotherapy system according to Example 1. FIG. FIG. 10 is a diagram showing an example of determination support data displayed in contour creation necessity determination operation of the radiotherapy system according to the first embodiment; FIG. 5 is a diagram showing an example of judgment support data displayed in the contour creation/verification operation of the radiotherapy system according to the first embodiment; FIG. 5 is a diagram showing an example of judgment support data displayed in the treatment plan selection operation of the radiotherapy system according to Example 1; FIG. 5 is a diagram showing an example of judgment support data displayed in the treatment plan evaluation operation of the radiotherapy system according to Example 1; 4 is a flow chart showing the operation of the radiotherapy system according to Example 1. FIG. 4 is a diagram showing a display example of a monitor in the radiotherapy system according to Example 1. FIG. 1 is a diagram showing a schematic configuration of a radiotherapy system according to Example 1; FIG. 4 is a flow chart showing the operation of the radiotherapy system according to Example 1. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and omissions and simplifications are made as appropriate for clarity of explanation. The present invention can also be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

In addition, in the diagrams for explaining the embodiments, portions having the same functions are denoted by the same reference numerals, and repeated description thereof will be omitted.

The position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. in order to facilitate the understanding of the invention. As such, the present invention is not necessarily limited to the locations, sizes, shapes, extents, etc., disclosed in the drawings.

When there are multiple components with the same or similar functions, they may be described with the same reference numerals and different subscripts. However, if there is no need to distinguish between these multiple constituent elements, the subscripts may be omitted in the description.

Embodiment 1 will be described with reference to FIGS. 1 to 18. FIG.

FIG. 1 is a diagram showing a schematic configuration of a radiotherapy system in Example 1. FIG.

The radiotherapy system of this embodiment includes a bed 2 for supporting an object (patient) 1, an imaging device 3 for imaging the object 1 during treatment, and a therapeutic radiation irradiation device 4 for irradiating the object with therapeutic radiation. and

In normal radiotherapy, a subject 1 is fixed on a bed 2, an imaging device 3 photographs the internal structure of the body, the bed 2 is moved with reference to the image, and the subject 1 is moved to a planned position. . Thereafter, therapeutic radiation is emitted from the therapeutic radiation irradiation device 4 to irradiate the target 5 in the subject with the radiation.

Here, the operator 11 creates a treatment plan for irradiating radiation including the position of the subject 1 using the treatment planning apparatus 10 before starting treatment. An operator 11 who operates the treatment planning apparatus 10 may be a doctor who performs radiotherapy, a radiological technologist, or the like. The treatment planning device 10 uses the image of the subject captured by the imaging device 3 or another imaging device in the hospital to grasp the internal structure of the body, and then evaluates the dose distribution to the target 5 and surrounding organs by simulation. A treatment plan including the irradiation method of therapeutic radiation is created while performing the treatment. Using the prepared treatment plan, the subject 1 is placed at the planned position, and the therapeutic radiation irradiation device 4 irradiates the target 5 with the planned dose, and the surrounding organs are also irradiated. In contrast, it is possible to keep the radiation dose as planned.

In this series of flows, structural changes occur in the patient's body from the treatment plan to the final day of treatment over multiple days. In the treatment planning of conventional treatment, in which the initially created treatment plan is used from the first day to the last day, this structural change is assumed in advance, and even if the structural change occurs, the desired dose is irradiated to the target. Plan to irradiate an area larger than the target itself. This makes it possible to apply a desired dose to the target even if irradiation is continued until the last day of treatment according to the initially created treatment plan.

On the other hand, on the day of treatment, if the patient's body structure is reassessed and the treatment plan is modified or newly created, adaptive treatment can be performed, eliminating the need for irradiation over a wide area in anticipation of structural changes The dose to organs can be further reduced.

In order to realize adaptive treatment, it is necessary to quickly modify the treatment plan on the day of treatment. will be Next, an outline of operations performed in the treatment control room 13 will be described. Note that the modification or re-creation of a treatment plan may hereinafter be referred to as re-planning.

First, the image captured by the imaging device 3 is sent to the patient structural change recognition device 14 via the network. The patient structure change recognizing device 14 compares the image of the subject that has just been photographed with the image of the subject at the time of treatment planning or at the time when the plan is revised on the subsequent treatment day, and recognizes the structure change of the subject. and generate the contour of each organ after the change. A non-rigid registration technique, a segmentation technique, or a combination of these techniques may be used to recognize this structural change and generate the contours of each organ. good.

The structural change information and the generated contour information of each organ are displayed on the monitor 12 and visually confirmed by the operator 11 . If the confirmed information is correct, the approval operation is performed, and if incorrect, the correction is performed manually. This approval work requires the operator 11 to have specialized knowledge such as how much structural change can be allowed. The approved structural change information, contour information of each organ, and captured image information are sent to the treatment planning apparatus 10 . Alternatively, in the case of software on the same computer, information is transmitted via a storage medium.

The treatment planning apparatus 10 uses the newly obtained image, contour information, etc. to determine the dose distribution when irradiation is performed according to the irradiation method determined in the plan. A dose evaluation index for each organ is calculated for the obtained dose distribution using the contour information. As dose indices, indices called maximum/minimum dose, dose flatness, and DVH (Dose Volume Histogram) are often used. The operator 11 determines whether or not irradiation correction is necessary based on these indices.

At this time, the criterion for judgment is whether or not the therapeutic effect assumed in the treatment plan can be obtained, but a vast amount of knowledge and experience is required to predict the therapeutic effect from the dose evaluation index. As a result of the determination, if re-planning is unnecessary, the process proceeds to irradiation as it is, and irradiation is performed by the therapeutic radiation irradiation device 4 . On the other hand, when re-planning is necessary, the irradiation method is re-optimized so as to satisfy the dose target for each organ set at the time of treatment planning.

In irradiation methods such as IMRT (Intensity Modulated Radiation Therapy) and VMAT (Volumetric Modulated Arc Therapy) in X-ray therapy, and scanning irradiation in particle beam therapy, there is a function that automatically determines the irradiation method so as to meet the dose target as much as possible. It's ready. At this time, it would be good if all the dose targets were met, but if they were not met, what priority should be given to meeting the dose targets and how to modify the dose distribution would require advanced judgment similar to that at the time of treatment planning. is required, and a wealth of experience is required to make decisions in the need for rapid adaptive treatment, especially online adaptive treatment. After completing the necessary modification of the irradiation method, the operator 11 performs an approval operation.

The approved treatment plan information is sent to the treatment plan verification device 15. The treatment plan verification device 15 verifies whether the dose distribution calculated by the treatment plan device 10 is appropriate. In normal treatment, this verification work is performed by an irradiation test involving the irradiation of actual therapeutic radiation. However, in the online adaptive therapy, the irradiation test cannot be performed because it must be performed with the subject 1 in the treatment room 6 . Instead, a method called independent verification may be used in which the dose distribution is compared with another calculation method. In the case of an independent validation, the dose distribution determined by another method is compared with the reoptimized distribution.

If there is a match in this comparison, there is no problem, but if there is a mismatch, it is necessary to judge on the spot whether it is within the treatable range. What causes the difference and whether it is within the permissible range depends on the case, so judgment based on abundant experience is required. If it is determined that it is within the allowable range, the operator 11 performs approval work.

Through the above flow, the approved replanned irradiation method data is created. From these overall operations, the operator 11 makes a comprehensive judgment as to whether to use the original planning data or the re-planning data, and determines which data to irradiate. to irradiation.

In this embodiment, the treatment planning device 10, the patient structural change recognition device 14, and the treatment plan verification device 15 are configured by devices capable of various types of information processing, such as information processing devices such as computers. An information processing apparatus has an arithmetic element, a storage medium, and a communication interface, and further has an input section such as a mouse and a keyboard, and a display section such as a display, if necessary.

Arithmetic elements are, for example, CPUs (Central Processing Units), FPGAs (Field-Programmable Gate Arrays), and the like. The storage medium includes, for example, a magnetic storage medium such as a HDD (Hard Disk Drive), a semiconductor storage medium such as a RAM (Random Access Memory), a ROM (Read Only Memory), and an SSD (Solid State Drive). A combination of an optical disk such as a DVD (Digital Versatile Disk) and an optical disk drive is also used as a storage medium. In addition, known storage media such as magnetic tape media are also used as storage media.

Programs such as firmware are stored in the storage medium. When the operation of the treatment planning apparatus 10 or the like is started (for example, when power is turned on), a program such as firmware is read from the storage medium and executed to control the entire treatment planning apparatus 10 or the like. In addition to the program, the storage medium stores data required for each process of the treatment planning apparatus 10 and the like.

It should be noted that the treatment planning apparatus 10 and the like of the present embodiment may each be configured by a so-called cloud in which information processing apparatuses are configured to be able to communicate via a communication network.

In this embodiment, a judgment support data input device 20 is provided to assist the operator 11 in making judgments at key points.

The decision support data input device 20 has a function of importing decision support data from outside the treatment facility into the treatment facility. Allows the use of decision support data created at other facilities with experienced staff within the treatment facility.

The decision support data is a set of decision support information classified by treatment site and treatment policy, as will be described in detail later with reference to FIGS. , Contour judgment index necessary for success/failure judgment after contour generation, dose evaluation index information for each part necessary for replanning, reference value and priority of each index, dose evaluation index information necessary for dose evaluation, criteria for each index Includes value/priority.

Structural change judgment indicators at the time of contour creation are volume change rate, contour deformation rate, etc. for each part (target). The dose evaluation indices necessary for replanning determination are the dose in the low-dose area, the dose in the high-dose area, the average dose, the DVH index, and the like. The DVH index is specified, for example, by a value such as the lowest dose irradiated to 95% or more of the volume, or a volume irradiated to 20% or more of the prescribed dose. Indices used when evaluating a treatment plan include, for example, the degree of coincidence of the distribution at the time of re-planning, changes in the degree of achievement of prescription for target DVH, changes in the degree of achievement of prescription for DVH in peripheral organs, and the like. For example, an index called the γ index can be used as the degree of agreement between the distributions. Divide the two dose distributions into small pieces, and measure the ratio of the small pieces that have a prescribed dose difference within a prescribed amount of movement. evaluate.

The decision support data will be described in more detail with reference to FIGS. 2 to 5.

The judgment support data consists of a judgment index and a judgment reference value. In addition, it is also possible to prioritize the necessity or the index for each judgment index.

Judgment support data includes hospitals and doctors, patient attributes (adult, child, obese, thin, male, female, etc.), tumor sites (liver, pancreas, lung, etc.). It may be further subdivided according to the position of the tumor in the organ, such as by dividing it into sections), and is created and stored for each treatment policy, and the operator 11 who performs treatment can select a suitable one from among them.

The judgment reference value is shown as XX% or XX mm, but it is not limited to this if the optimal display method can be selected for each doctor or hospital to be entered and the judgment standard is indicated.

　An example of structural change decision support data is shown in Figures 2 and 3.

For example, the shape change rate of the target, the shape change rate of the surrounding organs, the depth change rate from the body surface to the target, etc. are used as the judgment indicators for the structural change judgment support data. Of these, the shape change rate of the target and the shape change rate of the surrounding organs are essential items. The rate of change referred to here is the rate of change in the shape of the target from when the image was taken when the treatment plan was created to when the image was taken when the treatment was performed (for example, when the image was taken in S15 of FIG. 7, which will be described later).

As the rate of shape change of the target, for example, the rate of change in volume of the target, or the degree of volume matching of the target indicated by the Jaccard coefficient or the Dice coefficient is used. If there is a large change in the shape of the target, there is a high possibility that the dose and distribution of radiation to the target will deviate from the initial plan. Therefore, in order to carry out irradiation according to the initial plan, it is desirable that the shape change rate of the target is equal to or less than the criterion value. In addition to the volume change rate, a contour change rate such as a contour length change rate may be used.

As the shape change rate of the surrounding organs, for example, the volume change rate of the surrounding organs and the volume matching degree of the surrounding organs indicated by the Jaccard coefficient or the Dice coefficient are used. If there is a large change in the shape of the surrounding organs, there is a possibility that the surrounding organs will be exposed to more radiation than originally planned. Therefore, in order to carry out irradiation according to the initial plan, it is desirable that the rate of change in shape of peripheral organs is equal to or less than the criterion value. In addition to the volume change rate, a contour change rate such as a contour length change rate may be used.

As the depth change rate from the body surface to the target, for example, the water equivalent thickness change rate is used. When the irradiated radiation is a particle beam, the position in the depth direction where the maximum dose is emitted differs depending on the magnitude of the energy of the irradiated beam. Therefore, if the distance to the target in the depth direction or the equivalent water thickness changes, deviations will occur between the planned dose and distribution in the depth direction. Therefore, in order to carry out irradiation according to the initial plan, it is desirable that the rate of change in depth from the body surface to the target be equal to or less than the criterion value.

Judgment of what index is used and to what extent is permissible for irradiation according to the initial plan, such as the shape change rate of the target, the shape change rate of surrounding organs, and the depth change rate from the body surface to the target. is highly dependent on the experience of the physician. In the present embodiment, by obtaining and displaying the judgment index in advance, the judgment can be made more appropriate and faster, and highly accurate treatment can be performed in a short period of time.

Fig. 4 shows an example of replanning decision support data.

As the judgment index of the replanning judgment support data, for example, the dose in the low dose region of the target 5, the dose in the high dose region of the surrounding organs, the change in the distance between the surrounding organs and the end of the range, the prescription for DVH of the target 5 changes in the degree of achievement of DVH in peripheral organs, changes in the degree of achievement in prescription for DVH in peripheral organs, and the like are used.

For target 5, ideally the specified prescription dose is delivered uniformly over the target before replanning is made. However, it is difficult to make it completely uniform due to restrictions such as the position of the dangerous organ and the irradiation angle. However, it is desirable that the dose in the low-dose area within the target 5 is a dose equal to or higher than the prescribed dose reference value. Therefore, in this embodiment, for example, 90% or more of the prescribed dose is set.

It is necessary to concentrate the dose on target 5 and suppress the dose irradiated to normal peripheral organs. Therefore, it is desirable that the dose in the high-dose region of the peripheral organs is equal to or less than the reference value of the restricted dose. Therefore, in this embodiment, for example, the reference value is set at 110% or less of the restricted dose.

In addition, when a particle beam is used as radiation, the distance between the surrounding organs and the end of the range is kept at a predetermined distance or more in order to suppress the dose to the surrounding organs. make a treatment plan. Determine whether this distance has changed from the time of planning and is too close.

For example, an index of D○○ is used as the degree of achievement of prescription for target 5 DVH. This is the minimum dose that covers XX% of the volume of the target 5, and if D95=60Gy, it indicates that a dose of 60Gy or more is prescribed for 95% of the volume of the target 5.

This D95 = 60Gy is specified before the treatment plan is created, and the treatment plan is created so as to satisfy this index. In other words, since it is necessary to irradiate the target with a sufficient amount of dose, the change in the degree of achievement at the time of replanning should desirably be a value equal to or greater than the reference value. That is, if D95 = 60 Gy at the time of planning and the standard value is 5% or less, 95% of the volume of the target 5 If the change in dose prescribed is within 5%, that is, if D95 = 57 to 63 Gy, the standard is cleared. Become.

For example, the average dose is used as the degree of prescription achievement for DVH in peripheral organs. A constraint value for the average dose is specified before the treatment plan is created, such that the average dose prescribed for peripheral organs such as the pancreas is 10 Gy or less, and the treatment plan is created so as to satisfy this index. Since it is desirable that the dose to surrounding organs be low, it is desirable that the change in the degree of achievement at the time of re-planning is below the reference value.

Fig. 5 shows an example of decision support data for treatment plan evaluation.

As a judgment index of the judgment support data for treatment plan evaluation, the degree of agreement of the distribution at the time of re-planning, the dose of the target low-dose area, the dose of the high-dose area of the surrounding organs, the change in the degree of achievement of the prescription for the target DVH, A change in the degree of achievement of prescriptions for DVH in peripheral organs, and the like are used. A gamma analysis pass rate or the like is used as the degree of matching of the distribution at the time of replanning.

It is known that a general treatment planning apparatus 10 introduces data from the outside to create a treatment plan. In addition to this, this embodiment is characterized by introducing external judgment support data. More specifically, in calculating structural changes, it is known to incorporate an image of the subject that was just taken and an image of the subject at the time of treatment planning or at a later treatment date when the plan was modified. However, it is characterized by the introduction of a judgment index and a reference value to determine how much structural change can be tolerated. It is also known in re-planning to take as data the value of DVH to be achieved and to modify or recreate the treatment plan. On the other hand, for replanning, which is a treatment plan after recurrence, it is characterized by introducing a judgment index and a reference value to determine whether the desired dose has been achieved to some extent. Also, in the evaluation of the treatment plan, it is characterized by introducing a judgment index and a reference value to determine whether the desired dose has been achieved to some extent.

The decision support data taken into the facility is stored in the decision support database 21. The operator 11 accesses this decision support database 21 at the start of treatment and selects a set of decision support data that is appropriate for the subject to be treated. The selected decision support data sets are sent to the patient structural change recognizer 14, the treatment planer 10, and the treatment plan verifier 15, respectively.

Each device displays the type, priority, and reference value of the judgment index, calculates those values on the day of treatment, and displays them on the monitor 12. As shown in FIG. 18, on the display screen 40 of the monitor 12, a judgment index 41, a judgment reference value 42, and a calculated judgment 43 are displayed. is doing.

Looking at it, the operator 11 makes a judgment and performs an approval operation. Items to be referred to in judgment and their priority and standard values are displayed. can be referred to, making judgment easier.

In the system described above, the patient structure change recognition device 14, the treatment planning device 10, and the treatment plan verification device 15 are implemented in separate hardware and cooperated over a network. may be implemented as

Next, the operation of the radiotherapy system of this embodiment will be described with reference to the flow charts of FIGS. 6 to 12. FIG.

FIG. 6 is a flowchart showing the operation of the radiotherapy system according to Example 1, more specifically, a flowchart showing the flow of online adaptive radiotherapy by the radiotherapy system of this example.

First, in S0, the operator 11 selects decision support data suitable for the patient to be treated from the decision support database 21. Here, it is also possible to select the structural change decision support data, the replanning decision support data, and the treatment plan evaluation decision support data all at once from the characteristics of the hospital and patient that created the decision support data, and the site of the cancer. good. Further, the operator may individually select the structural change decision support data, the replanning decision support data, and the treatment plan evaluation decision support data.

Next, the decision support database 21 transmits the decision support data selected by the operator 11 to the patient structural change recognition device 14 , the treatment planning device 10 and the treatment plan verification device 15 .

Although this S0 is executed at the start of the overall workflow shown in FIG. 6, the selection and/or transmission of the judgment support data may be performed at any time before displaying the judgment support data. That is, the selection/transmission of the structural change decision support data may be performed prior to S25 shown in FIG. 8, and the selection/transmission of the replanning decision support data may be performed prior to S47 shown in FIG. The selection/transmission of the decision support data for plan evaluation may be performed before S67 shown in FIG.

Next, in S1, the patient 1 is fixed to the bed 2, the bed 2 is moved, and the patient 1 is moved to the treatment position. In S2, it is determined whether or not it is necessary to create the contour of each organ from the image captured on the treatment day of the patient 1 .

In S3, if the outline of the organ needs to be created (Yes in S3), proceed to S4. If it is not necessary to create the outline of the organ (No in S3), the process proceeds to S8.

In S4, the contours of each organ are created and the created contours are verified from the images taken on the day of treatment. At S5, the contour created at S4 is used to re-plan the treatment plan. At S6, the treatment plan re-planned at S5 is evaluated and the treatment plan created at the time of planning and the re-planned treatment plan are selected. If this selection selects the replanned treatment plan, S7 may be performed, and if the treatment plan created at the time of planning is selected, S7 may be skipped and S8 may be performed. At S7, the treatment plan evaluated and selected at S6 is evaluated.

In S8, if the evaluation results of S7 are approved without any problems, radiation is emitted from the therapeutic radiation irradiation device 4 to the patient 1 according to the approved treatment plan. At this time, the emitted radiation is stored as a log. At S9, the logs output at S8 are evaluated and the series of adaptive workflow controlled treatment room 6 irradiations is completed.

FIG. 7 is a flowchart showing the positioning operation of the radiotherapy system according to Example 1, and is a flowchart showing details of S1 in FIG. The operation shown in the flowchart of FIG. 7 is performed by a positioning device (not shown) provided in the therapeutic radiation irradiation apparatus 4 .

First, in S11, the patient 1 is fixed on the bed 2. After the patient 1 is fixed, the bed 2 is moved using a laser that indicates the isocenter position so that the irradiation center (isocenter) of radiation and the affected area are roughly aligned. It is also possible to fix the patient 1 to the bed 2 after photographing the state of the body of the patient 1 on the day of treatment with the imaging device 3 . Also, after fixing the patient 1, before moving the patient 1 to the isocenter, the photographing device 3 may be used to photograph the internal state of the patient 1 on the day of treatment, and then the patient may be moved to the isocenter position.

Next, in S13, in order to image the inside of the body of the patient 1 moved to the isocenter position, the imaging parameters are set according to the position of the affected part of the patient 1, body type, and the like. The imaging parameters may be set automatically from the information of the patient 1, or may be set manually. The imaging may be performed by moving the imaging device 3 to the isocenter, or may be performed by another imaging device attached to the therapeutic radiation irradiation device 4 or the like. Moreover, there is no fixed order of execution of S11 and S13, and S13 may be executed first.

Next, in S15, the operator 11 instructs imaging, and the imaging device 3 images the inside of the patient 1. In S17, the amount of movement for matching the affected area of the patient 1 with the isocenter is calculated from the image captured during treatment planning and the image captured in S15. In S19, when the operator 11 approves the movement, the bed 2 on which the patient 1 is placed is moved so that the affected part of the patient 1 and the isocenter are precisely aligned.

FIG. 8 is a flowchart showing contour creation necessity determination operation of the radiotherapy system according to the first embodiment, and is a flowchart showing details of S2 in FIG. The operation shown in the flowchart of FIG. 8 is performed by the patient structural change recognition device 14 .

First, in S21, the water equivalent thickness (WET) is calculated from the image taken on the day of treatment. The water-equivalent thickness obtained from the image at the time of treatment planning is compared with the water-equivalent thickness from the image taken on the day of treatment, and the change ΔWET of the water-equivalent thickness is calculated. Note that although WET is calculated as an example here, other determination indexes may be used. The determination index to be calculated may be obtained by acquiring the structural change determination support data, identifying the determination index included in the acquired structural change determination support data, and calculating the identified determination index.

In S25, the results calculated in S21 and structural change determination support data are displayed. In S25, as shown in FIG. 13, a judgment index, a judgment reference value, and a judgment index value are displayed. The judgment index and the judgment reference value are the values obtained from the judgment support data, and the judgment index value is the value calculated on the day. The priority of each index may also be displayed so that the operator 11 can easily judge. A result of comparing the judgment reference value and the judgment index value may be displayed. Further, only the judgment index and the comparison result may be displayed without displaying the judgment reference value and the judgment index value.

Then, in S27, the operator 11 selects and inputs whether contour creation is necessary while referring to the determination support data.

FIG. 9 is a flowchart showing the contour creation/verification operation of the radiotherapy system according to Embodiment 1, and is a flowchart showing details of S4 in FIG. The operation shown in the flowchart of FIG. 9 is performed by the patient structural change recognition device 14 .

First, in S41 and S43, the patient structural change recognizing device 14 is set with the subject image that has just been photographed and the subject image at the time of treatment planning or at the time when the plan is revised on the subsequent treatment date. The patient structure change recognizing device 14 compares the image of the subject that has just been photographed with the image of the subject at the time of treatment planning or at the time when the plan is revised on the subsequent treatment day, and recognizes the structure change of the subject. and generate the contour of each organ after the change.

A non-rigid image registration (deformable image registration: DIR) technique may be used for recognition of this structural change and contour generation of each organ (OAR (Organ at Risk), target, peripheral organ), A segmentation technique may be used, or a combination of these techniques may be used. Here, the volumes of the target and surrounding organs used for comparison are also obtained from the structural change determination support data. Although the calculation of the volume of the target and surrounding organs has been described here as an example, other determination indices may be used. The determination index to be calculated may be obtained by acquiring the structural change determination support data, identifying the determination index included in the acquired structural change determination support data, and calculating the identified determination index.

Next, in S45, the created contour data is set in the contour verification device (program) to verify whether the contour has been created.

In S47 and S49, as shown in FIG. 14, the structural change information and the generated contour information of each organ are displayed on the monitor 12 and visually confirmed by the operator 11. If the confirmed information is correct, the approval operation is performed, and if incorrect, the correction is performed manually. The approved structural change information, contour information of each organ, and captured image information are sent to the treatment planning apparatus 10 . Alternatively, in the case of software on the same computer, information is transmitted via a storage medium.

In addition, in the flowchart shown in FIG. 9, S41 to S43 and S45 to S49 may be executed by different devices.

FIG. 10 is a flowchart showing the treatment plan selection operation of the radiotherapy system according to Example 1, and is a flowchart showing details of S6 in FIG. The operation shown in the flowchart of FIG. 10 is executed by the treatment plan verification device 15 .

First, in S61, the image taken on the day and the treatment plan created at the time of planning are used to calculate the dose when irradiation is performed according to the treatment plan created at the time of planning. For example, the dose distribution of the treatment plan created from the images at the time of planning is obtained by transforming it according to the images taken on the day. Next, in S63, a new treatment plan is created and the dose is calculated when radiation is irradiated using an irradiation method different from that at the time of planning, such as the irradiation angle and irradiation energy. The execution order of S61 and S63 is not fixed, and S63 may be executed first. In the dose calculations of S61 and S63, the DVH value to be achieved that was specified at the time of planning is used, or a new DVH to be achieved is specified.

Furthermore, in S65, the dose evaluation index for each organ is calculated using the contour information for the doses obtained in S61 and S63. As dose indices, indices called maximum/minimum dose, dose flatness, and DVH (Dose Volume Histogram) are often used. Items included in the judgment support data selected in S0 may be acquired and the acquired items may be calculated.

In S67, as shown in FIG. 15, the evaluation index and evaluation reference value included in the judgment support data, and the evaluation index value calculated in S65 are displayed.

In S69, the operator 11 determines whether or not irradiation correction is necessary based on these indices. At this time, whether or not the therapeutic effect assumed in the treatment plan can be obtained is the criterion for judgment, but a vast amount of knowledge and experience is required to predict the therapeutic effect from the dose evaluation index. As a result of the determination, if re-planning is unnecessary, the process proceeds to irradiation as it is, and irradiation is performed by the therapeutic radiation irradiation device 4 . On the other hand, when re-planning is necessary, the irradiation method is re-optimized so as to satisfy the dose target for each organ set at the time of treatment planning.

In irradiation methods such as IMRT (Intensity Modulated Radiation Therapy) and VMAT (Volumetric Modulated Arc Therapy) in X-ray therapy, and scanning irradiation in particle beam therapy, there is a function that automatically determines the irradiation method so as to meet the dose target as much as possible. It's ready. At this time, it would be good if all the dose targets were met, but if they were not met, what priority should be given to meeting the dose targets and how to modify the dose distribution would require advanced judgment similar to that at the time of treatment planning. is required, and extensive experience is required to make judgments in the need for prompt online adaptive treatment. When the necessary modification of the irradiation method is completed, the operator 11 performs approval operation.

In other words, select whether to perform irradiation according to the treatment plan at the time of treatment planning or to perform irradiation according to the newly created (re-planned) treatment plan. When the treatment plan at the time of treatment planning is selected, the process proceeds to S9 in FIG. If the data plan for replanning is selected, the process proceeds to S7 in FIG. 6, and the approved treatment plan information is sent to the treatment plan verification device 15.

FIG. 11 is a flowchart showing the treatment plan evaluation operation of the radiotherapy system according to Example 1, and is a flowchart showing details of S7 in FIG. The operation shown in the flowchart of FIG. 11 is executed by the treatment plan verification device 15 .

The treatment plan verification device 15 verifies whether the dose distribution calculated by the treatment planning device 10 is appropriate. In normal treatment, this verification work is performed by an irradiation test involving the irradiation of actual therapeutic radiation. However, in the online adaptive therapy, the irradiation test cannot be performed because it must be performed with the subject 1 in the treatment room 6 . Instead, a method called independent verification may be used in which the dose distribution is compared with another calculation method. In the case of an independent validation, the dose distribution determined by another method is compared with the reoptimized distribution. If there is agreement in this comparison, there is no problem, but if there is a disagreement, it is necessary to judge on the spot whether it is within the treatable range. What causes the difference and whether it is within the permissible range depends on the case, so judgment based on abundant experience is required. If it is determined that it is within the allowable range, the operator 11 performs approval work.

First, in S71, the dose is calculated independently from the daily dose calculated in S61 of FIG. 10, based on the image of patient 1 at the time of treatment and the contour of each organ. Next, in S73, it is verified whether or not the therapeutic radiation irradiation apparatus 4 operates to irradiate radiation according to the treatment plan approved in S69 of FIG. It should be noted that S71 and S73 may operate independently or may be reversed in order.

In S75, as shown in FIG. 16, the result calculated in S71 and the judgment support data for treatment plan evaluation are displayed. Note that, as already shown in FIG. 10, the judgment index has already been calculated at this point. Then, in S<b>77 , the treatment plan approved by the operator 11 is transmitted to the therapeutic radiation irradiation device 4 .

FIG. 12 is a flowchart showing the radiation irradiation operation of the radiotherapy system according to Example 1, and is a flowchart showing details of S8 and S9 in FIG. The operation shown in the flowchart of FIG. 12 is performed by the therapeutic radiation irradiation apparatus 4 for S8 and by the treatment plan verification apparatus 15 for S9.

First, in S81, when the operator 11 instructs irradiation, the therapeutic radiation irradiation device 4 irradiates the patient 1 with radiation according to the treatment plan approved in S69 of FIG. In S83, the therapeutic radiation irradiation apparatus 4 generates a log of the position and dose of the irradiated radiation and the operation of the apparatus. The generated log is sent to the treatment plan verification device 15 .

In S91, the treatment plan verification device 15 compares the treatment plan with the log, and evaluates the actually irradiated position and dose (actual dose evaluation). Then, in S93, the treatment plan verification device 15 verifies whether the operation of the device was accurate.

FIG. 17 is a flowchart showing the operation of the radiotherapy system according to Example 1, and is a flowchart extracting and showing the main part of the operation of this example.

First, in S102, the operator 11 inputs judgment support data using the judgment support data input device 20 in advance before treatment. In the next S<b>103 , the judgment support data input device 20 saves the judgment support data in the judgment support database 21 .

In the next S104, the operator 11 selects decision support data suitable for the patient to be treated. In the next step S105, the decision support database 21 transmits the decision support data to the patient structural change recognition device 14, the treatment planning device 10, and the treatment plan verification device 15. FIG. These S104 and 105 correspond to S0 in FIG.

In the next S106, the patient structure change recognition device 14, the treatment planning device 10, and the treatment plan verification device 15 display the type, reference value, and degree of achievement of the judgment index based on the judgment support data. In the next step 107, the operator 11 confirms the index and performs an approval operation. When the approval operation is performed in all of the above steps, the therapeutic radiation irradiation device irradiates the therapeutic beam. These S106 and S107 correspond to S25 to S27 in FIG. 8, S47 to S49 in FIG. 9, and S67 to S69 in FIG.

Therefore, according to the radiotherapy system of the present embodiment, appropriate evaluation indices, reference values for success or failure, and priorities necessary for judgment during treatment are given, and judgment can be made while confirming the degree of achievement thereof. Therefore, an inexperienced operator can make an appropriate judgment in a short time and perform adaptive treatment.

In other words, according to the present embodiment, it is possible to incorporate judgment indices and reference values created in advance at a hospital with experienced staff into treatment at a hospital with inexperienced staff. It is possible to rapidly incorporate new treatment methods that require judgment of In addition, by optimizing and speeding up the judgment during treatment, high-precision treatment in a short period of time becomes possible.

In this embodiment, an example is shown in which the judgment support data input device 20 takes in the judgment support data from outside the treatment facility, but the judgment support data created inside the treatment facility may be input. Also, the judgment support data may be corrected/updated by AI or the like based on the results.

The radiotherapy system of Example 2 will be described with reference to FIGS. 19 and 20. FIG.

In contrast to the radiotherapy system of Embodiment 1, in the radiotherapy system of Embodiment 2, the judgment support data input device 20 is connected to the cloud server 30, and the judgment support data input device 20 acquires data as appropriate. As a result, the data in the decision support database is always up-to-date, and newly developed treatment methods can be rapidly introduced.

Here, the judgment support data includes the requirements of suitable devices, the judgment support data input device 20 judges the suitability, and only the judgment support data suitable for the facility is stored in the judgment support database 21. , it is possible to prevent irradiation using unsuitable data, and it is possible to quickly introduce treatment data. Indices for judging suitability for a facility include the type and performance of the imaging device, the radiation irradiation accuracy of the therapeutic radiation irradiation device, the corresponding irradiation technique, and the like. Also, the introduced data may be edited to reflect the characteristics of the facility. Specifically, if the accuracy of patient positioning is improved by using a characteristic method or the patient's movement is restricted by a characteristic method, the reference value of the judgment index should be changed. Highly accurate treatment can be supported.

FIG. 20 is a system flow diagram of the second embodiment. S102 and S103 are changed to S201 and S202 in the flowchart of the first embodiment (FIG. 17).

First, in S<b>201 , the judgment support data input device 20 acquires the judgment support data from the cloud server 30 . Next, in S<b>202 , only data whose device information included in the decision support data acquired by the decision support data input device 20 matches the facility is stored in the decision support database 21 . The above data are classified according to the site to be treated and the treatment method, and the suitability is determined and stored individually.

Therefore, the radiotherapy system of this embodiment can also obtain the same effect as the radiotherapy system of the first embodiment.

It should be noted that the present invention is not limited to the above examples, and includes various modifications. The above embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the described configurations. It is also possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Moreover, it is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

In addition, each of the above configurations, functions, processing units, processing means, etc., may be implemented in hardware, for example, by designing a part or all of them using an integrated circuit. Moreover, each of the above configurations, functions, etc. may be realized by software by a processor interpreting and executing a program for realizing each function. Information such as programs, tables, and files that implement each function can be stored in a memory, a hard disk, a recording device such as an SSD, or a recording medium such as an IC card, an SD card, and a DVD.

In addition, control lines and information lines indicate what is considered necessary for explanation, and not all control lines and information lines are necessarily indicated on the product. In practice, it may be considered that almost all configurations are interconnected.

1: Subject 2: Bed 3: Imaging Device 4: Therapeutic Radiation Irradiation Device 5: Target 6: Treatment Room 10: Treatment Planning Device 11: Operator 12: Monitor 13: Treatment Control Room 14: Patient Structural Change Recognition Device 15: Treatment Plan verification device 20: Judgment support data input device 21: Judgment support database 30: Cloud server 40: Display screen 41: Judgment index 42: Judgment reference value 43: Judgment index value 44: Achievement

Claims

Receiving input of decision support data consisting of a set of a decision index and a decision reference value to be evaluated during radiation therapy, receiving selection input of the decision support data to be used for each target of the radiation therapy, and receiving the target on the day of treatment The value of the determination index is calculated for an image of the predetermined area captured by an imaging device that captures the predetermined area including decision support system.
The decision support system according to claim 1, comprising a decision support database that holds the decision support data.
The decision support system according to claim 1, wherein the value of the decision index is calculated based on the decision support data.
2. The determination index value is calculated based on the image of the predetermined area captured by the imaging device, during the operation of determining whether contour creation of the organ existing in the image is necessary. Judgment support system according to.
2. The determination according to claim 1, wherein the calculation of the value of the determination index is performed during contour creation of an organ existing in the image of the predetermined area captured by the imaging device. support system.
6. The determination according to claim 4, wherein the determination index includes at least one of a shape change rate of the target, a shape change rate of the organ, and a depth change rate from the body surface to the target. support system.
　The decision support system according to claim 1, wherein the calculation of the value of the decision index is performed at the time of treatment replanning evaluation of the radiation therapy.
The judgment index is the dose in the target low-dose area, the dose in the high-dose area of the organ, the change in the distance between the organ and the end of the range, and the degree of achievement of the prescription for the dose volume histogram of the target. 8. The decision support system of claim 7, comprising at least one of: a change in the dose-volume histogram of the organ;
　The decision support system according to claim 1, characterized in that the calculation of the value of the decision index is performed when evaluating the treatment plan of the radiation therapy.
The decision index is the degree of agreement of the distribution at the time of re-planning the radiation therapy, the dose of the target low-dose region, the dose of the high-dose region of the organ, the change in the degree of achievement of the prescription with respect to the dose volume histogram of the target, 10. The decision support system of claim 9, comprising at least one of a change in prescription attainment relative to the dose-volume histogram of the organ.
The decision support system according to claim 1, wherein at least one of priority and necessity is assigned to the decision index.
2. An input of treatment apparatus information corresponding to said decision support data is accepted, and said decision support data determines whether said treatment apparatus information matches a radiation irradiation apparatus of a facility where treatment is performed. Judgment support system according to.
　The decision support system according to claim 1, which accepts editing input of the decision index that reflects the characteristics of the facility where the treatment is performed.
3. The decision support system according to claim 2, wherein a selection input of the decision index is accepted, and an input of the decision support data is accepted from the decision support database based on the selected decision index.
an imaging device for imaging a predetermined area including a target;
a radiation irradiation device for irradiating the target with radiation;
an irradiation control device for controlling the radiation irradiation device;
with
The irradiation control device accepts input of judgment support data consisting of a set of a judgment index and a judgment reference value to be evaluated during treatment, receives selection input of the judgment support data to be used for each of the targets, and receives the imaging on the treatment day. A radiotherapy system, wherein the value of the judgment index is calculated for the image of the predetermined region captured by the apparatus, and the value of the judgment index and the judgment reference value are compared and displayed.
A judgment support method in a judgment support system,
Receiving input of decision support data consisting of a set of a decision index and a decision reference value to be evaluated during radiation therapy, accepting input of selection of said decision support data to be used for each target of radiation therapy, including said target on a treatment day. The value of the judgment index is calculated for an image of the predetermined area captured by an imaging device that photographs the predetermined area, and the value of the judgment index and the judgment reference value are compared and displayed. A decision support method in a decision support system.