Particle beam therapy system and particle beam therapy method

Abstract

The present invention provides a particle beam therapy system and a particle beam therapy method that can shorten the time required for switching between layers. [Solution] The control unit 30 performs layer switching-related processing to switch the layer to which the particle beam is irradiated. Here, if the irradiation parameter switching processing time in which the control unit 30 switches the irradiation parameters of the particle beam is long, the time required for layer switching may be long. In contrast, in the particle beam therapy system 1, the irradiation parameter switching processing time in which the control unit 30 switches the irradiation parameters of the particle beam is shorter than the time of other switching processing. As a result, the overall time for layer switching can be shortened by shortening the irradiation parameter switching processing time.

Description

[Technical Field]

[0001] The present invention relates to a particle beam therapy system and a particle beam therapy method. [Background technology]

[0002] Conventionally, particle beam therapy systems are known that treat patients by irradiating the affected area with charged particle beams. Patent Document 1 describes a particle beam therapy system in which the irradiated body is divided into multiple layers, and each layer is irradiated by scanning with a charged particle beam using a scanning method. Such a particle beam therapy system irradiates with charged particle beams based on a treatment plan created by a treatment planning system. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-065655 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] Here, when switching between layers irradiated with particle beams, shortening the time required for switching between layers can shorten the treatment time. This reduces the burden on the irradiated body. For these reasons, shortening the time required for switching between layers was desired.

[0005] This invention was made to solve these problems and aims to provide a particle beam therapy system and a particle beam therapy method that can shorten the time required for switching between layers. [Means for solving the problem]

[0006] The particle beam therapy system according to the present invention is a particle beam therapy system that irradiates an irradiated object, which is virtually sliced ​​into multiple layers, with a particle beam sequentially by a scanning method, and comprises an accelerator that accelerates particles and emits a particle beam, an irradiation unit that irradiates the irradiated object with the particle beam by a scanning method, and a control unit, wherein the control unit performs layer switching-related processing to switch the layer to which the particle beam is irradiated, and among the layer switching-related processing, the time for irradiation parameter switching processing in which the control unit switches the irradiation parameters of the particle beam is shorter than the time for other switching processing.

[0007] In a particle beam therapy system, the control unit performs layer switching-related processing to switch the layer to which the particle beam is irradiated. If the irradiation parameter switching process, in which the control unit switches the particle beam irradiation parameters, takes a long time, the time required for layer switching may increase. In contrast, in a particle beam therapy system, the irradiation parameter switching process, in which the control unit switches the particle beam irradiation parameters, takes less time than the other switching processes. As a result, the overall time for layer switching can be reduced by shortening the irradiation parameter switching process. Therefore, the time for layer switching can be reduced.

[0008] Other switching processes may include an electromagnet power supply switching process that switches the settings of the electromagnet power supply in conjunction with the switching of layers, and a degrader switching process that switches the amount of energy adjustment of the degrader in conjunction with the switching of layers.

[0009] The particle beam therapy system according to the present invention is a particle beam therapy system that irradiates an irradiated object, which is virtually sliced ​​into multiple layers, with a particle beam sequentially applied to each layer by a scanning method, and comprises an accelerator that accelerates particles and emits a particle beam, an irradiation unit that irradiates the irradiated object with the particle beam by a scanning method, and a control unit, wherein the control unit has a switching control panel that transmits commands to equipment involved in layer switching-related processing to switch the layer to which the particle beam is irradiated, and the switching control panel transmits commands to the equipment without going through other control panels.

[0010] In a particle beam therapy system, the control unit has a switching control panel that transmits commands to equipment involved in layer switching related processing, which switches the layer to which the particle beam is irradiated. The switching control panel transmits commands to the equipment without going through other control panels. In this case, the switching control panel can transmit commands to the equipment quickly. As a result, the time for layer switching can be shortened.

[0011] The switching control panel may transmit commands to the equipment and electromagnet power supply that are subject to the switching of particle beam irradiation parameters, without going through other control panels. By transmitting commands to these equipment and electromagnet power supplies without going through other control panels, a time reduction effect can be effectively obtained.

[0012] An Ethernet-based open network may be used as the communication method between the control unit and the equipment involved in layer switching-related processing. In this case, the speed at which commands are transmitted can be increased, and the layer switching time can be shortened.

[0013] The particle beam therapy method according to the present invention is a particle beam therapy method in which a target to be irradiated, which is virtually sliced ​​into multiple layers, is irradiated with a particle beam sequentially to each layer by a scanning method, and a layer switching-related process is performed to switch the layer to which the particle beam is irradiated, and the time for the irradiation parameter switching process, which switches the irradiation parameters of the particle beam, is shorter than the time for the other switching processes.

[0014] The particle beam therapy method according to the present invention is a particle beam therapy method in which a particle beam is irradiated sequentially to each layer of an irradiated object that has been virtually sliced ​​into multiple layers by a scanning method, and a switching control panel that transmits commands to equipment involved in layer switching-related processing to switch the layer to which the particle beam is irradiated transmits the commands to the equipment without going through other control panels.

[0015] These particle beam therapy methods can achieve similar effects and benefits to the particle beam therapy systems described above. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a particle beam therapy system and a particle beam therapy method capable of shortening the time for layer switching.

Brief Description of the Drawings

[0017] [Figure 1] FIG. 1 is a schematic diagram showing an embodiment of a particle beam irradiation system according to the present invention. [Figure 2] FIG. 2 is a block configuration diagram showing the functions of a control unit. [Figure 3] FIG. 3 is a diagram showing parameter settings and an irradiation image of a charged particle beam. [Figure 4] FIG. 4 is a diagram showing the system configuration of a particle beam therapy system. [Figure 5] FIG. 5 is a diagram showing the system configuration of a particle beam therapy system according to a comparative example. [Figure 6] FIG. 6 is a graph showing the time required for layer switching in a particle beam therapy system according to a comparative example and an embodiment.

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The terms "upstream" and "downstream" respectively mean the upstream (accelerator side) and downstream (patient side) of the emitted charged particle beam.

[0019] As shown in Figure 1, the particle beam therapy system 1 is a device used for cancer treatment by radiotherapy, and comprises an accelerator 11 that accelerates charged particles and emits a charged particle beam (particle beam), an irradiation nozzle 12 (irradiation unit) that irradiates a target with the charged particle beam, a beam transport line 13 that transports the charged particle beam emitted from the accelerator 11 to the irradiation nozzle 12, a degrader 18 provided in the beam transport line 13 that reduces the energy of the charged particle beam to adjust its range, a plurality of electromagnets 25 provided in the beam transport line 13, an electromagnet power supply 27 provided in correspondence to each of the plurality of electromagnets 25, and a control unit 30 that controls the entire particle beam therapy system 1. In this embodiment, a cyclotron is used as the accelerator 11, but it is not limited to this, and other sources that generate charged particle beams, such as a synchroton, synchrocycloton, linac, etc., may also be used.

[0020] In the particle beam therapy system 1, the tumor (irradiated body) of patient P on the treatment table 22 is irradiated with a charged particle beam emitted from the accelerator 11. A charged particle beam is a particle with an electric charge accelerated to high speed, and examples include proton beams and heavy particle (heavy ion) beams. The particle beam therapy system 1 according to this embodiment irradiates with a charged particle beam using a so-called scanning method, virtually dividing (slicing) the irradiated body in the depth direction, and irradiating the irradiation area on each slice plane (layer) with a charged particle beam (see, for example, Figure 3).

[0021] There are two types of irradiation methods using the scanning method: spot-type scanning irradiation and raster-type scanning irradiation. Spot-type scanning irradiation is a method in which, once irradiation of one spot (the irradiation area) is completed, the beam (charged particle beam) irradiation is stopped, and irradiation of the next spot is resumed after preparation for irradiation of the next spot is complete. In contrast, raster-type scanning irradiation is a method in which the beam irradiation is performed continuously without stopping the irradiation in the irradiation area of ​​the same layer. Thus, since raster-type scanning irradiation is performed continuously within the irradiation area of ​​the same layer, unlike spot-type scanning irradiation, the irradiation area does not consist of multiple spots. In the following, we will explain an example of irradiation performed by spot-type scanning irradiation, and will explain it as if the irradiation area on the same layer consists of multiple spots, but it is not limited to this, and when irradiation is performed by raster-type scanning irradiation, the irradiation area does not have to consist of spots as described above.

[0022] The irradiation nozzle 12 is mounted inside a rotating gantry 23 that can rotate 360 ​​degrees around the treatment table 22, and can be moved to any rotational position by the rotating gantry 23. The irradiation nozzle 12 includes a focusing electromagnet 19 (details described later), a scanning electromagnet 21, and a vacuum duct 28. The scanning electromagnet 21 is located inside the irradiation nozzle 12. The scanning electromagnet 21 has an X-direction scanning electromagnet that scans the charged particle beam in the X direction on a plane intersecting the irradiation direction of the charged particle beam, and a Y-direction scanning electromagnet that scans the charged particle beam in the Y direction intersecting the X direction on a plane intersecting the irradiation direction of the charged particle beam. Furthermore, since the charged particle beam scanned by the scanning electromagnet 21 is deflected in the X direction and / or Y direction, the diameter of the vacuum duct 28 downstream of the scanning electromagnet is increased towards the downstream side.

[0023] The beam transport line 13 has a vacuum duct 14 through which the charged particle beam passes. The inside of the vacuum duct 14 is maintained in a vacuum state, which suppresses scattering of the charged particles constituting the transported charged particle beam by air or other means.

[0024] Furthermore, the beam transport line 13 includes an Energy Selection System (ESS) 15 that selectively extracts charged particle beams with an energy width narrower than a predetermined energy width from a charged particle beam with a predetermined energy width emitted from the accelerator 11, a Beam Transport System (BTS) 16 that transports the charged particle beam with the energy width selected by the ESS 15 while maintaining its energy, and a Gantry Transport System (GTS) 17 that transports the charged particle beam from the BTS 16 toward the rotating gantry 23.

[0025] The degrader 18 adjusts the range of the charged particle beam by reducing its energy. Since the depth from the patient's body surface to the tumor, which is the target of irradiation, varies from patient to patient, it is necessary to adjust the range of the charged particle beam when irradiating a patient with a charged particle beam. The degrader 18 adjusts the energy of the charged particle beam emitted from the accelerator 11 at a constant energy so that the charged particle beam reaches the target of irradiation at a predetermined depth inside the patient's body appropriately. This energy adjustment of the charged particle beam by the degrader 18 is performed for each layer sliced ​​from the target of irradiation. For example, the degrader 18 can switch the amount of energy adjustment by switching the thickness of the attenuating material through which the charged particle beam passes, according to the layer.

[0026] Multiple electromagnets 25 are provided in the beam transport line 13 and adjust the charged particle beam so that it can be transported in the beam transport line 13 by magnetic field. The electromagnets 25 include focusing electromagnets 19 that converge the beam diameter of the transported charged particle beam, and deflecting electromagnets 20 that deflect the charged particle beam. In the following, focusing electromagnets 19 and deflecting electromagnets 20 may be referred to simply as electromagnets 25 without distinction. Furthermore, multiple electromagnets 25 are provided at least downstream of the degrader 18 in the beam transport line 13. However, in this embodiment, electromagnets 25 are also provided upstream of the degrader 18. Here, focusing electromagnets 19 are also provided upstream of the degrader 18 to converge the beam diameter of the charged particle beam before energy adjustment by the degrader 18. The total number of electromagnets 25 can be flexibly changed depending on the length of the beam transport line 13, for example, between 10 and 40. Although only a portion of the electromagnet power supplies 27 are shown in Figure 1, in reality, the same number of power supplies as the number of electromagnets 25 are provided.

[0027] The positions of the degrader 18 and electromagnet 25 within the beam transport line 13 are not particularly limited, but in this embodiment, the ESS 15 is provided with the degrader 18, focusing electromagnet 19, and deflection electromagnet 20. The BTS 16 is provided with the focusing electromagnet 19, and the GTS 17 is provided with the focusing electromagnet 19 and deflection electromagnet 20. The degrader 18 is provided in the ESS 15, which is located between the accelerator 11 and the rotating gantry 23, as described above, and more specifically, it is provided in the ESS 15 on the accelerator 11 side (upstream side) of the rotating gantry 23.

[0028] The electromagnet power supply 27 generates a magnetic field for the corresponding electromagnet 25 by supplying current to it. The electromagnet power supply 27 can set the strength of the magnetic field for the corresponding electromagnet 25 by adjusting the current supplied to it. The electromagnet power supply 27 adjusts the current supplied to the electromagnet 25 in accordance with a signal from the control unit 30 (details will be described later). An electromagnet power supply 27 is provided to correspond one-to-one with each electromagnet 25. That is, there are as many electromagnet power supplies 27 as there are electromagnets 25.

[0029] The relationship between the depth of each layer of the irradiated object and the current supplied to the electromagnet 25 is as follows. That is, the energy of the charged particle beam required to irradiate each layer is determined by the depth of each layer, and the energy of the charged particle beam emitted from the accelerator 11 and the amount of energy adjustment by the degrader 18 are determined. Here, if the energy of the charged particle beam changes, the strength of the magnetic field required to deflect and focus the charged particle beam also changes. Therefore, the current supplied to the electromagnet 25 is determined so that the strength of the magnetic field of the electromagnet 25 corresponds to the energy of the charged particle beam from the accelerator 11 and the amount of energy adjustment by the degrader 18.

[0030] Next, the details of the control unit 30 and the electromagnet power supply 27 will be explained with reference to Figure 2. Although only three electromagnet power supplies 27 are shown in Figure 2, in reality, there are as many corresponding electromagnet power supplies 27 as there are electromagnets 25 installed in the particle beam therapy system 1. Also, although electromagnets 25 are not shown in Figure 2, in reality, there are electromagnets 25 that are electrically connected to the electromagnet power supplies 27.

[0031] The control unit 30 controls the irradiation of the irradiated object with charged particle beams emitted from the accelerator 11. The control unit 30 includes a main control unit 31, a beam control unit 32, an ESS control unit 33, a BTS control unit 34, a GTS control unit 35, a scanning control unit 36, and a layer control unit 37.

[0032] The main control unit 31 controls the beam control unit 32 and the scanning control unit 36. Specifically, the main control unit 31 starts processing by sending a processing start signal to the beam control unit 32 and the scanning control unit 36, and ends processing by sending a processing end signal.

[0033] The beam control unit 32 controls each function so that the charged particle beam can be irradiated onto the target object. Specifically, in response to a processing start signal from the main control unit 31, the beam control unit 32 transmits a processing start signal to the cycloton control unit (not shown), causing the accelerator 11 to emit the charged particle beam. The beam control unit 32 also transmits processing start signals to the ESS control unit 33, BTS control unit 34, and GTS control unit 35 in response to the processing start signal from the main control unit 31.

[0034] The ESS control unit 33 turns on the power to the electromagnet power supply 27 corresponding to the electromagnet 25 installed in the ESS 15 in response to a processing start signal from the beam control unit 32. Similarly, the BTS control unit 34 turns on the power to the electromagnet power supply 27 corresponding to the electromagnet 25 installed in the BTS 16 in response to a processing start signal from the beam control unit 32. Similarly, the GTS control unit 35 turns on the power to the electromagnet power supply 27 corresponding to the electromagnet 25 installed in the GTS 17 in response to a processing start signal from the beam control unit 32. Through this control of the accelerator 11 by the beam control unit 32, and the control of the electromagnet power supplies 27 by the ESS control unit 33, BTS control unit 34, and GTS control unit 35, the charged particle beam emitted from the accelerator 11 becomes ready to irradiate the target object, after which the scanning control unit 36 ​​performs further control.

[0035] The scanning control unit 36 ​​controls the scanning of the charged particle beam onto the irradiated object. In response to a processing start signal from the main control unit 31, the scanning control unit 36 ​​sends an irradiation start signal to the scanning electromagnet 21, causing the scanning electromagnet 21 to irradiate multiple irradiation spots on the same layer. Information regarding the irradiation spots in each layer is stored in the scanning control unit 36 ​​in advance. Furthermore, once the scanning electromagnet 21 has completed irradiating all spots in a layer, the scanning control unit 36 ​​sends a layer switching signal to the layer control unit 37. This layer switching signal includes information that identifies the layer to be switched to (for example, the second layer, etc.).

[0036] The charged particle beam irradiation image of the scanning electromagnet 21 in accordance with the control of the scanning control unit 36 ​​will be explained with reference to Figures 3(b) and (c). Figure 3(b) shows the irradiated object virtually sliced ​​into multiple layers in the depth direction, and Figure 3(c) shows the scanning image of the charged particle beam in one layer as viewed from the direction of irradiation of the charged particle beam.

[0037] As shown in Figure 3(b), the irradiated object is virtually sliced ​​into multiple layers in the depth direction. In this example, the layers are named L1, L2, ... L1, starting from the deepest layer (where the range of the charged particle beam B is long). n-1 , layer L n , layer L n+1 ,...layer L N-1 , layer L N It is virtually sliced ​​into N layers. Also, as shown in Figure 3(c), the irradiation beam B traces a beam trajectory TL while passing through layer L n The beam is directed to multiple irradiation spots. That is, the irradiation nozzle 12 controlled by the scanning control unit 36 ​​moves along the beam trajectory TL.

[0038] Returning to Figure 2, the layer control unit 37 performs layer switching-related processing to switch the layer irradiated with the charged particle beam in response to the layer switching signal from the scanning control unit 36. The layer switching-related processing consists of degrader setting processing, which changes the energy adjustment amount of the degrader 18, and electromagnet setting processing, which sets the parameters of the electromagnet 25 to match the energy adjustment amount of the degrader 18 after the degrader setting processing. The parameters of the electromagnet 25 are the target values ​​of the current supplied to the electromagnet 25.

[0039] In particle beam therapy, a plan is made (treatment plan) for how to irradiate a patient with charged particle beams before treatment is performed. The treatment plan data determined during this planning stage is transmitted from the treatment planning device (not shown) to the layer control unit 37 of the control unit 30 before treatment is performed and stored in the layer control unit 37. This treatment plan data includes the energy of the charged particle beam from the accelerator 11 for irradiating each layer of the irradiated body, the energy adjustment amount of the degrader 18, and the parameters of the electromagnet 25 for irradiating all layers according to the energy of the charged particle beam. The treatment plan data also includes irradiation parameters related to the irradiation of the charged particle beam for irradiating each layer of the irradiated body.

[0040] The layer control unit 37 performs a degrader switching process as part of the layer switching-related processing, which involves switching the energy adjustment amount of the degrader 18 in accordance with the layer switching. The degrader switching process includes a degrader setting process that sets the energy adjustment amount of the degrader 18, and a drive process that drives the degrader 18 based on the set energy amount. As described above, the layer control unit 37 has in advance stored the energy adjustment amounts of the degrader 18 for irradiating each layer of the irradiated object with a charged particle beam. Then, in response to the layer switching signal from the scanning control unit 36, the layer control unit 37 sets the energy adjustment amount of the degrader 18 to a value corresponding to the layer after the switch.

[0041] The layer control unit 37 performs electromagnet power supply switching processing as part of layer switching-related processing, which involves switching the settings of the electromagnet power supply 27 in accordance with the layer switching. Specifically, the layer control unit 37 simultaneously transmits a layer switching signal to each electromagnet power supply 27, thereby setting the parameters of the electromagnet 25 to correspond to the energy adjustment amount of the degrader 18 after the degrader setting processing. Here, the layer switching signal that the layer control unit 37 transmits to the electromagnet power supply 27 simply contains information that identifies the layer after the switch, and does not contain the parameters of the electromagnet 25 corresponding to the layer after the switch (parameters of the electromagnet 25 corresponding to the energy adjustment amount of the degrader 18 after the degrader setting processing). The parameter change of the electromagnet 25 is performed by the electromagnet power supply 27. As a prerequisite, the layer control unit 37 transmits the parameters of the electromagnet 25 for irradiating all layers corresponding to the energy adjustment amount of the degrader 18 from the treatment plan data described above to the electromagnet power supply 27 before irradiation starts (not immediately before irradiation (switching) to a layer, but before treatment starts).

[0042] The electromagnet power supply 27 sets the parameters of the electromagnet 25 corresponding to the switched layer (parameters of the electromagnet 25 corresponding to the energy adjustment amount of the degrader 18 after the degrader setting process) in response to the layer switching signal received from the layer control unit 37. Specifically, the electromagnet power supply 27 has a storage unit 27a that stores the parameters of the electromagnet 25 corresponding to each layer, and when it receives a layer switching signal from the layer control unit 37, it sets the parameters corresponding to the switched layer included in the layer switching signal. As a result, a current corresponding to the switched layer is supplied to the electromagnet 25.

[0043] The parameter setting for the electromagnet power supply 27 will be explained with reference to Figure 3(a). As shown in Figure 3(a), all electromagnet power supplies 27 are set for each layer of the irradiated object, specifically layers L1 to L1. N (See Figure 3(b)) Parameters D1~D of electromagnet 25 corresponding to Nis stored. Then, the electromagnet power supply 27 sets the parameter D according to the information (L = n) specifying the layer after switching included in the layer switching signal SG transmitted from the layer control unit 37. n is set.

[0044] Incidentally, after transmitting the layer switching signal to the electromagnet power supply 27, the layer control unit 37 determines that the parameter setting of the electromagnet power supply 27 is completed after a predetermined time (for example, 50 msec to 200 msec) has elapsed, and transmits a switching completion signal to the scanning control unit 36. Then, the scanning control unit 36 transmits an irradiation start signal to the scanning electromagnet 21 in response to the switching completion signal. The layer control unit 37 may adopt a known technique in order to shorten the time of the electromagnet power supply switching process, for example, the technique disclosed in Japanese Patent Application Laid-Open No. 2015-181655 may be adopted.

[0045] As layer switching related processing, the layer control unit 37 performs irradiation parameter switching processing for switching the irradiation parameters of the charged particle beam. The layer control unit 37 transmits a signal for switching the irradiation parameters to the device 50 related to the irradiation parameter switching processing. The device 50 is not particularly limited as long as it needs to switch the irradiation parameters according to the layer switching. For example, a dose monitor 51 (see FIG. 4) for detecting a charged particle beam, a timing system 52, and the like can be mentioned.

[0046] Here, among the layer switching-related processes, the irradiation parameter switching process, in which the layer control unit 37 switches the irradiation parameters of the charged particle beam, takes less time than the other switching processes. Specifically, the irradiation parameter switching process takes less time than the electromagnet power supply switching process and less time than the degrader switching process (see, for example, Figure 6(b)). The irradiation parameter switching process takes less time than the time from when the layer control unit 37 starts setting the irradiation parameters to be switched in each device 50 until the setting of the irradiation parameters in each device 50 is completed. The electromagnet power supply switching process takes less time than the time from when the layer control unit 37 starts setting the parameters of each electromagnet power supply 27 until the setting of the parameters in each electromagnet power supply 27 is completed. The degrader switching process takes less time than the time from when the layer control unit 37 starts setting the energy adjustment amount for the degrader 18 until the degrader 18 is driven and the energy adjustment is completed. The configuration for establishing these time relationships will be explained with reference to Figure 4.

[0047] As shown in Figure 4, the particle beam therapy system 1 includes a switching control panel 60 which constitutes part of the control unit 30. The switching control panel 60 has the functions of the layer control unit 37 shown in Figure 2. The switching control panel 60 transmits commands to equipment involved in layer switching related processing, which involves switching the layer to which the charged particle beam is irradiated. The switching control panel 60 transmits commands to equipment involved in layer switching related processing without going through other control panels. Specifically, the switching control panel 60 transmits commands to the dose monitor 51, multiple electromagnet power supplies 27, degrader 18, equipment 53, and timing system 52 without going through other control panels. The dose monitor 51 is a detector installed, for example, in the irradiation nozzle 2, which measures the dose of the charged particle beam. The timing system 52 is a system that checks the irradiation time in scanning irradiation. The timing system 52 has a timer and can measure the irradiation time of each layer, thereby checking the length of the irradiation time for each layer. The timing system 52 has an interlock mechanism that stops the charged particle beam when the irradiation time exceeds a predetermined time.

[0048] The switching control panel 60 is connected to the dose monitor 51, multiple electromagnet power supplies 27, and degrader 18 via communication channel L1, without going through other control panels. The switching control panel 60 is connected to the equipment 53 via communication channel L2, without going through other control panels. The switching control panel 60 is connected to the timing system 52 via communication channel L3, without going through other control panels. The switching control panel 60 transmits commands to the ion source 54 and ion chamber 56 of the accelerator 11 via another accelerator control panel 61. The switching control panel 60 is connected to the accelerator control panel 61 via communication channels L3 and L4. The accelerator control panel 61 is connected to the ion source 54 and ion chamber 56 via communication channel L5. When the accelerator control panel 61 receives a switching command from the switching control panel 60, it transmits the command to the ion source 54 and ion chamber 56.

[0049] As a communication method between the switching control panel 60 and the equipment involved in the switching process, a high-speed communication-capable Ethernet®-based open network (industrial Ethernet) may be used. This communication method can also be described as communication using a field network. For example, EtherCAT® may be adopted as the communication method. That is, EtherCAT® may be adopted as the communication method for communication channels L1, L2, L3, L4, and L5. This enables high-speed communication between the switching control panel 60 and each piece of equipment.

[0050] When performing degrader switching processing, the switching control panel 60 transmits an energy adjustment command to the degrader 18 without going through other control panels. When performing electromagnet power supply switching processing, the switching control panel 60 transmits parameter commands to the electromagnet power supply 27 without going through other control panels. When performing irradiation parameter switching processing, the switching control panel 60 transmits irradiation parameter commands to the equipment 50, namely the dose monitor 51 and the timing system 52, without going through other control panels.

[0051] Figure 5 shows a particle beam therapy system 100 according to a comparative example, in which the switching control panel 60 is connected to the dose monitor 51 via control panel 66. The switching control panel 60 is connected to the timing system 52 and the electromagnet power supply 27 via control panel 67. The switching control panel 60 is connected to the ion source 54 and the ion chamber 56 via accelerator control panel 61. The switching control panel 60 is connected to the degrader 18, the electromagnet power supply 27, and the magnetic field detection unit 29 via control panel 62 corresponding to the ESS control unit 33. The switching control panel 60 is connected to the electromagnet power supply 27 via control panel 63 corresponding to the BTS control unit 34. The switching control panel 60 is connected to the electromagnet power supply 27 via control panel 64 corresponding to the GTS control unit 35. In Figure 5, communication channels shown by solid lines are constructed by hardwires. Communication channels shown by dashed lines are constructed by DeviceNet. Communication methods such as Ethenet / IP and GPIB are used in communication channels shown by dashed lines. Thus, EtherCAT® is not used in the particle beam therapy system 100 related to the comparative example.

[0052] Next, the operation and effects of the particle beam therapy system 1 and the particle beam therapy method according to this embodiment will be described.

[0053] The particle beam therapy system 1 according to this embodiment is a particle beam therapy system 1 that irradiates an irradiated object, which is virtually sliced ​​into multiple layers, with a particle beam sequentially by scanning, into each layer, and comprises an accelerator 11 that accelerates particles and emits a particle beam, an irradiation nozzle 12 that irradiates the irradiated object with the particle beam by scanning, and a control unit 30, wherein the control unit 30 performs layer switching-related processing to switch the layer to which the particle beam is irradiated, and among the layer switching-related processing, the time for irradiation parameter switching processing in which the control unit 30 switches the irradiation parameters of the particle beam is shorter than the time for other switching processing.

[0054] In particle beam therapy system 1, the control unit 30 performs layer switching-related processing to switch the layer to which the particle beam is irradiated. Here, if the irradiation parameter switching processing time in which the control unit 30 switches the irradiation parameters of the particle beam is long, the time required for layer switching may be long. In contrast, in particle beam therapy system 1, the irradiation parameter switching processing time in which the control unit 30 switches the irradiation parameters of the particle beam is shorter than the time of other switching processing. As a result, the overall time for layer switching can be shortened by shortening the irradiation parameter switching processing time. Therefore, the time for layer switching can be shortened.

[0055] Other switching processes may include an electromagnet power supply switching process that switches the settings of the electromagnet power supply 27 in conjunction with the switching of layers, and a degrader switching process that switches the energy adjustment amount of the degrader 18 in conjunction with the switching of layers.

[0056] The particle beam therapy system 1 according to this embodiment is a particle beam therapy system 1 that irradiates an object to be irradiated, which is virtually sliced ​​into multiple layers, with a particle beam sequentially applied to each layer by a scanning method, and comprises an accelerator 11 that accelerates particles and emits a particle beam, an irradiation nozzle 12 that irradiates the object to be irradiated with the particle beam by a scanning method, and a control unit 30, the control unit 30 having a switching control panel 60 that transmits commands to equipment involved in layer switching-related processing that switches the layer to be irradiated with the particle beam, and the switching control panel 60 transmits commands to the equipment without going through other control panels.

[0057] In the particle beam therapy system 1, the control unit 30 has a switching control panel 60 that transmits commands to equipment involved in layer switching related processing for switching the layer to which the particle beam is irradiated. The switching control panel 60 transmits commands to the equipment without going through other control panels. In this case, the switching control panel 60 can transmit commands to the equipment quickly. As a result, the time for switching layers can be shortened. In addition, time lags due to communication between control panels and variations in processing time can be reduced. By adopting such a structure, for example, the time lag of about 20 to 50 ms that occurs when going through a control panel can be reduced to about 4 to 8 ms.

[0058] The switching control panel 60 may transmit commands to the equipment 50 and the electromagnet power supply 27, which are the targets for switching the particle beam irradiation parameters, without going through other control panels. By transmitting commands to these equipment 50 and the electromagnet power supply 27 without going through other control panels, a time reduction effect can be effectively obtained.

[0059] An Ethernet-based open network may be used as the communication method between the control unit 30 and the equipment involved in layer switching-related processing. In this case, the speed at which commands are transmitted can be increased, and the layer switching time can be shortened. For example, EtherCAT®, which enables high-speed control, can be adopted as the communication method. EtherCAT is faster and more synchronous than DeviceNet communication. For example, the communication time, which was 20-40ms in the case of DeviceNet communication, can be reduced to 4ms.

[0060] The particle beam therapy method according to this embodiment is a particle beam therapy method in which a particle beam is irradiated sequentially to each layer of an irradiated object that has been virtually sliced ​​into multiple layers by a scanning method, and a layer switching-related process is performed to switch the layer to which the particle beam is irradiated, and the time for the irradiation parameter switching process, which switches the irradiation parameters of the particle beam, is shorter than the time for the other switching processes.

[0061] The particle beam therapy method according to this embodiment is a particle beam therapy method in which a particle beam is irradiated sequentially to each layer of an irradiated object that has been virtually sliced ​​into multiple layers, by a scanning method, and a switching control panel that transmits commands to equipment involved in layer switching-related processing to switch the layer to which the particle beam is irradiated transmits the commands to the equipment without going through other control panels.

[0062] These particle beam therapy methods can achieve similar effects and benefits to the particle beam therapy system 1 described above.

[0063] Figure 6(a) is a graph showing the time required to switch the irradiation target layer in the particle beam therapy system 100 according to the comparative example. First, the control unit 30 starts switching the energy of the charged particle beam, and then the electromagnet power supply switching process, degrader switching process, and irradiation parameter switching process start, respectively. The time for the electromagnet power supply switching process (120 ms) is longer than the time for the degrader switching process (60 ms), and the time for the irradiation parameter switching process (160 ms) is longer than the time for the electromagnet power supply switching process. In addition, after each switching process is completed, a time lag occurs before irradiation to the new layer can be started (see the "Irradiation Start" section). In the conventional particle beam therapy system 100, the overall time is extended by about 125 ms due to control processing, communication time, etc., and the total time required to switch layers is about 250 ms.

[0064] In contrast, Figure 6(b) is a graph showing the time required to switch the irradiated layer in the particle beam therapy system 1 according to this embodiment. By optimizing the system as described above, the overall layer switching time can be reduced by further shortening the communication time and processing time. Specifically, the time for electromagnet power supply switching can be reduced to 60 ms. In addition, the irradiation parameter switching time, which was particularly long (160 ms) in the comparative example, can be reduced to 20 ms, making it shorter than other switching processes. In this embodiment, the overall time required for layer switching can be reduced by shortening the irradiation parameter switching time, which was particularly long in the comparative example. In addition, the communication time can be reduced from 125 ms to 10 ms overall. As a result, the time required for layer switching can be kept below 100 ms. [Explanation of Symbols]

[0065] 1...Particle beam irradiation system, 11...Accelerator, 12...Irradiation nozzle (irradiation unit), 18...Degrader, 25...Electromagnet, 27...Electromagnet power supply, 30...Control unit.

Claims

1. A particle beam therapy system that irradiates an object to be irradiated, which is virtually sliced ​​into multiple layers, with particle beams sequentially by a scanning method, An accelerator that accelerates particles and emits the particle beam, An irradiation unit that irradiates the object to be irradiated with the particle beam by the scanning method described above, It comprises a control unit and, The control unit performs layer switching related processing to switch the layer to which the particle beam is irradiated, Of the layer switching related processes, A particle beam therapy system in which the time required for the irradiation parameter switching process, in which the control unit switches the irradiation parameters of the particle beam, is shorter than the time required for other switching processes.

2. The other switching processes mentioned above are: An electromagnet power supply switching process that switches the settings of the electromagnet power supply in conjunction with the switching of the aforementioned layer, The particle beam therapy system according to claim 1, further comprising a degrader switching process that switches the energy adjustment amount of the degrader in conjunction with the switching of the aforementioned layer.

3. A particle beam therapy system that irradiates an object to be irradiated, which is virtually sliced ​​into multiple layers, with particle beams sequentially by a scanning method, An accelerator that accelerates particles and emits the particle beam, An irradiation unit that irradiates the object to be irradiated with the particle beam by the scanning method described above, It comprises a control unit and, The control unit has a switching control panel that transmits commands to equipment involved in layer switching related processing for switching the layer to which the particle beam is irradiated, The switching control panel transmits the commands to the equipment without going through other control panels, in a particle beam therapy system.

4. The particle beam therapy system according to claim 3, wherein the switching control panel transmits the command to the equipment to which the particle beam irradiation parameters are to be switched, and to the electromagnet power supply, without going through the other control panel.

5. The particle beam therapy system according to claim 4, wherein the device to which the irradiation parameters are switched is at least one of a dose monitor and a timing system.

6. The particle beam therapy system according to any one of claims 1 to 5, wherein an Ethernet-based open network is used as the communication method between the control unit and the equipment involved in the layer switching related processing.

7. A particle beam therapy method in which a target object, virtually sliced ​​into multiple layers, is irradiated with particle beams sequentially to each layer using a scanning method, Layer switching related processing is performed to switch the layer to which the particle beam is irradiated. Of the layer switching related processes, A particle beam therapy method in which the time required for switching the irradiation parameters of the particle beam is shorter than the time required for other switching processes.

8. A particle beam therapy method in which a target object, virtually sliced ​​into multiple layers, is irradiated with particle beams sequentially to each layer using a scanning method, A particle beam therapy method wherein a switching control panel that transmits commands to equipment involved in layer switching related processing for switching the layer to which the particle beam is irradiated transmits the commands to the equipment without going through other control panels.

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