JP2013009967A - Particle beam irradiation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely and efficiently perform irradiation with improved irradiation accuracy by appropriately performing a beam emission processing (interruption and restart) when an abnormality occurs during the irradiation of spot aggregation.SOLUTION: A particle beam irradiation system includes: a synchrotron 12; and a scanning irradiation device 15 having scanning electromagnets 5A, 5B and scanning an ion beam emitted from the synchrotron 12. The emission of the ion beam from the synchrotron 12 is stopped on the basis of a beam emission stop command. In this state, the scanning electromagnets 5A, 5B are controlled to change ion beam irradiation positions (spots). After the change, the emission of the ion beam from the synchrotron 12 is started. When a comparatively slight abnormality capable of continuing the irradiation occurs during the irradiation of the beam to a certain irradiation spot, the beam emission is not immediately stopped but is stopped when the irradiation is completed concerning the whole spots belonging to the predefined spot aggregation including the irradiation spot.

Description

  The present invention relates to a particle beam irradiation system and a control method thereof, and more particularly to a particle beam irradiation system and a control method thereof for irradiating an affected area with a charged particle beam such as protons and carbon ions.

  There is known a treatment method in which an affected part of a patient such as cancer is irradiated with a charged particle beam (ion beam) such as proton and carbon ion. The particle beam irradiation system used for this treatment includes a charged particle beam generator, a beam transport system, and an irradiation device.

  As an irradiation method of the irradiation device, a scatterer method in which a beam is expanded by a scatterer and then cut out according to the shape of the affected area, or a scanning method in which a fine beam is scanned in the affected area is known.

  In the particle beam irradiation system using the scanning method, the charged particle beam accelerated by the accelerator of the charged particle beam generator reaches the irradiation device through the beam transport system, and is scanned by the scanning electromagnet provided in the irradiation device. Thereafter, the affected area of the patient is irradiated from the irradiation device.

  In this method, the charged particle beam output is stopped by controlling the energy and the scanning electromagnet in a state where the output of the charged particle beam is stopped and the output of the charged particle beam is stopped in accordance with the integrated irradiation amount to the irradiation target. By changing the irradiation position (spot) and restarting the output of the charged particle beam from the extraction device after completion of the change, irradiation is performed sequentially on the irradiation target (affected part) while switching the irradiation position (for example, , See Patent Document 1).

  In the particle beam therapy system described in Patent Literature 1, in order to prevent exposure to healthy cells as much as possible and perform correct irradiation treatment without excess or deficiency, the irradiation device includes a downstream of the electromagnet and immediately before the patient to be irradiated. In addition, a beam position monitor and an irradiation dose monitor are installed as an irradiation amount detection device for measuring the irradiation amount of the charged particle beam to the irradiation position.

  In general, the beam position monitor is often a method in which the amount of charge ionized by the passage of the beam is accumulated in a capacitor and the voltage induced in the capacitor is read after spot irradiation. The ionization charge amount at the spot having the largest value among them is determined to be acceptable. Further, the resolution with the above method is higher as the capacitance of the capacitor is smaller, and lower as the capacitance is larger.

  In the scanning particle beam irradiation system, the irradiation target is divided into several spots (irradiation positions), the number of irradiations for divided irradiation and the irradiation amount per time are set in advance. By irradiating a spot in multiple steps, the amount of irradiation (irradiation time) per spot is reduced, variation is suppressed, and more accurate detection and evaluation of actual irradiation dose (such as dose distribution) It is devised so that it can be evaluated.

  On the other hand, the overall control system in the particle beam irradiation system monitors abnormalities in equipment and components, beam conditions in the accelerator, etc., and is in the process of irradiating a spot depending on the type and level of the generated factor. In addition, an interlock is provided to stop or interrupt the irradiation. In addition, it is possible to interrupt or cancel the operation by a manual operation (button operation or the like).

  In addition, respiratory synchronization control may be applied to the particle beam irradiation system. Respiration synchronization control interrupts and resumes irradiation in synchronization with the patient's breathing. The beam is controlled according to the breathing gate signal synchronized with the patient's breathing (when this signal is ON, the beam is emitted). Start and stop irradiation.

  Therefore, if an abnormality occurs during irradiation of a spot, or if the breathing gate is turned OFF and irradiation is stopped or interrupted halfway, the irradiation amount (irradiation time) for that spot will be the expected amount depending on the timing of the occurrence. On the other hand, it may be a very small value. Considering the characteristics of the position monitor described above and the influence of background noise, it is difficult to accurately detect the irradiation position. As an irradiation position detection device, it is difficult to accurately detect the actual irradiation amount at the irradiation position, and it is also difficult to accurately perform the evaluation (evaluation of dose distribution and the like). Further, in this case, due to the occurrence of an abnormality, irradiation of one spot is performed in a plurality of times with an amount smaller than the planned irradiation amount, and it is further difficult to accurately detect and evaluate the actual irradiation amount for that spot. In addition, when the entire system is considered, it is a factor that hinders efficient operation of the system.

  In response to this problem, the particle beam therapy system described in Patent Document 2 immediately emits (irradiates) a charged particle beam when a relatively mild abnormality (which can be continued) occurs during irradiation of a certain spot. Without stopping, wait for the irradiation dose to the spot to reach the target dose value, and then stop.

  As a result, even if an abnormality occurs during irradiation of a certain spot, irradiation to the spot is continued, so that irradiation of one spot is reliably performed without being divided into two or more times at an intermediate stage. It is possible to perform the irradiation once, and the actual irradiation dose will not be very small compared to the planned irradiation amount (irradiation time). Evaluation of dose distribution and the like).

Japanese Patent No. 3681744 Japanese Patent Publication No. 2008-237687

  However, the prior art described in Patent Document 2 has the following problems. The distribution of irradiation dose evaluates not only the dose of one spot but also a set of spots, and it may be better to manage it as a set of spots. During irradiation of a set of spots that belong to the same energy, etc., if an abnormality occurs, or if the breathing gate is turned off and irradiation is stopped or interrupted halfway, depending on the timing of the occurrence, As a result, the distribution of the irradiation dose is divided so that the irradiation spot position at the time of irradiation interruption and the irradiation spot position at the time of irradiation interruption resumption do not necessarily match, and there are gaps and overlaps where irradiation cannot be predicted. It is considered that a desired irradiation dose distribution cannot be obtained for a certain set of spots.

  It is an object of the present invention to appropriately perform beam extraction processing (interruption and resumption) when an abnormality occurs during irradiation of a set of spots, thereby increasing the irradiation accuracy and enabling safe and efficient irradiation. An illumination system and a control method thereof are provided.

  The feature of the present invention for achieving the above-described object is that charging is performed when a relatively mild abnormality (which can be continued) occurs during irradiation of a spot or when the respiratory synchronization gate is turned off. The irradiation (irradiation) of the particle beam is not stopped immediately, but the irradiation is interrupted or stopped after the scheduled irradiation is completed for all spots belonging to the set of spots including the spot.

  As a result, even if an abnormality occurs during irradiation of a certain spot, or even if the respiratory synchronization gate is turned off, irradiation to that spot set is continued. It is possible to perform the irradiation with one irradiation without dividing it into two or more times, and there is no gap or overlap in the dose distribution of the entire set of spots.

  However, according to the present invention, even when an abnormality occurs, irradiation can be continued depending on the type and level of the generated factor. From the viewpoint of safety of the patient and the operator, the type and level of the factor that can continue irradiation. The selection of is very important.

  According to the present invention, even if a relatively mild abnormality occurs during irradiation of a certain spot, or even when the breathing synchronization gate is turned off, the irradiation to the set of spots is continued. The irradiation dose distribution can be controlled more accurately by reliably performing the irradiation on the set of the above by dividing the irradiation into one or more times without dividing the irradiation into a plurality of times.

  In addition, suppressing the irradiation of a single set of spots from being divided into multiple times in the middle leads to shortening of the treatment time and is effective in terms of efficient system operation. It is.

It is a conceptual diagram which shows the whole structure of the proton beam irradiation system which is one Embodiment of the particle beam irradiation system of this invention. It is a conceptual diagram showing the detail of the scanning irradiation apparatus of the proton beam irradiation system which is one embodiment of the particle beam irradiation system of the present invention. It is a conceptual diagram showing an example of the dose distribution irradiated in each layer in order to ensure the uniformity of the dose distribution in an affected part area | region. It is a figure showing an example of layering of the affected part area | region which is the irradiation object of the particle beam irradiation system shown in FIG. It is a part of the treatment plan information planned by the treatment plan apparatus shown in FIG. 1, and is a diagram showing the contents of a command signal for performing scanning irradiation of each layer at the time of irradiation. 2 shows an example of a control flow executed by the control system (central processing unit, scanning controller, accelerator controller) shown in FIG. 1 in normal irradiation. In the conventional system, an example of a control flow executed by a control system (central processing unit, scanning controller, accelerator controller) when an irradiation interruption factor occurs during spot irradiation is shown. In the present embodiment, an example of a control flow executed by the control system (central processing unit, scanning controller, accelerator controller) shown in FIG. 1 when an irradiation interruption factor occurs during spot irradiation is shown. . It is a time chart which shows an example of the control pattern of the ion beam in a conventional system, and the relationship of irradiation to each spot. It is a time chart which shows an example of the control pattern of the ion beam in this Embodiment, and the relationship of irradiation to each spot. This shows the effect of dose distribution due to misalignment in the case of interruption or resumption during the irradiation of a set of spots. It is a figure explaining the set of spots in the 1st example. It is a figure explaining the set of spots in the 3rd example.

  A particle beam irradiation system according to an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic diagram of a proton beam irradiation system which is a particle beam irradiation system of the present embodiment, and FIG. 2 is a schematic diagram of a scanning irradiation apparatus constituting the particle beam irradiation system of the present embodiment.

  In FIG. 1, a particle beam treatment system performs treatment by irradiating a diseased part of a patient fixed to a treatment bed in a treatment room with a charged particle beam (for example, a proton beam). A beam transport system 4 connected to the downstream side of the charged particle beam generator 1, a scanning irradiation device 15 connected to the transport system 4 for irradiating the affected area of the patient with the charged particles, the charged particle beam generator, the beam A control system 90 is provided for controlling the transport system and the scanning irradiation device 15 based on the treatment plan.

  The charged particle beam generator 1 includes an ion source (not shown), a pre-stage charged particle beam generator (linac) 11, and a synchrotron (accelerator) 12. The synchrotron 12 has a high-frequency application device 9 and an acceleration device 10. The high-frequency applying device 9 is configured by connecting a high-frequency applying electrode 93 and a high-frequency power source 91 arranged on the orbit of the synchrotron 12 by an open / close switch 92.

  The acceleration device (charged particle beam energy changing device) 10 includes a high-frequency accelerating cavity (not shown) arranged in its orbit and a high-frequency power source (not shown) for applying high-frequency power to the high-frequency accelerating cavity. .

  Ions (for example, proton ions (or carbon ions)) generated in the ion source are accelerated by the preceding charged particle beam generator 11 (for example, a linear charged particle beam generator).

  The ion beam (proton beam) emitted from the preceding charged particle beam generator 11 is incident on the synchrotron 12.

  The ion beam, which is a charged particle beam (particle beam), is accelerated by a synchrotron 12 by being given energy by a high frequency power applied to the ion beam from a high frequency power source through a high frequency acceleration cavity.

  After the energy of the ion beam that circulates in the synchrotron 12 is increased to a set energy (for example, 100 to 200 MeV), the high frequency for emission from the high frequency power supply 91 is applied to the high frequency via the closed open / close switch 92. It reaches the electrode 93 and is applied to the ion beam from the high-frequency applying electrode 93.

  The ion beam orbiting within the stability limit moves outside the stability limit by the application of this high frequency, and is emitted from the synchrotron 12 through the extraction deflector 8. When the ion beam is emitted, the current guided to the quadrupole electromagnet 13 and the deflection electromagnet 14 provided in the synchrotron 12 is held at the current set value, and the stability limit is also kept almost constant.

  By opening the open / close switch 92 and stopping the application of the high-frequency power to the high-frequency application electrode 93, the extraction of the ion beam from the synchrotron 12 is stopped.

  The ion beam emitted from the synchrotron 12 is transported downstream from the beam transport system 4. The beam transport system 4 includes a quadrupole electromagnet 21, a quadrupole electromagnet 22, a quadrupole electromagnet 21, a quadrupole electromagnet 22, a quadrupole electromagnet 21, a quadrupole electromagnet 22, and a quadrupole electromagnet 22, which are arranged from the upstream side in the beam traveling direction. A deflection electromagnet 23 and a deflection electromagnet 24 are provided. The ion beam introduced into the beam transport system 4 is transported to the scanning irradiation device 15 through the beam path 62.

  A rotating gantry (not shown) is installed inside the treatment room, and the scanning irradiation device 15 includes a part of the beam transport system and a substantially cylindrical rotating drum (not shown) of the rotating gantry (not shown). ). The rotating drum can be rotated by a motor (not shown), and a treatment gauge (not shown) is formed in the rotating drum.

  In the casing (not shown) of the scanning irradiation device 15, an incident position monitor (FIG. 1) detects the incident position of the beam from the upstream side in the beam traveling direction (the lower direction in FIGS. 1 and 2, the Z direction in FIG. 2). Scanning electromagnets 5A and 5B for scanning the beam, a beam position monitor 6A for detecting the beam scanning position, a dose monitor 6B for detecting the irradiation dose at the beam scanning position, and the like are installed.

  The scanning electromagnets 5A and 5B are for, for example, deflecting the beam in directions orthogonal to each other (X direction and Y direction) on a plane perpendicular to the beam axis and moving the irradiation position in the X direction and the Y direction.

  As shown in FIG. 2, these scanning electromagnets 5A and 5B are connected to scanning electromagnet power supplies 7A and 7B, and power supply control for controlling the current supplied from the scanning electromagnet power supplies 7A and 7B to the scanning electromagnets 5A and 5B. A device 42 is provided. The power supply control device 42 controls the supply current to the scanning electromagnets 5A and 5B according to the control signal from the scanning irradiation control device 41, and controls the excitation magnetic fields of the scanning electromagnets 5A and 5B, respectively. The charged particle beams are deflected by the excitation magnetic fields of the scanning electromagnets 5A and 5B controlled in this way.

  The beam position monitor 6A detects whether or not the beam scanning position by the scanning electromagnets 5A and 5B is at the control position (set value), and the detection signal is output to the scanning position measuring device 11A to determine the beam scanning position. The calculated data is output to the scanning irradiation control device 41.

  The dose monitor 6B detects the irradiation dose at the beam scanning position detected by the beam position monitor 6A. The detection signal is output to the dose measuring device 11B, the dose value is calculated, and the calculated data is scanned and irradiated. It is output to the control device 41.

  The beam position monitor 6A and the dose monitor 6B constitute a dose detection device that measures the dose of the charged particle beam to the irradiation position at that time and measures the dose distribution.

  Returning to FIG. 1, the treatment bed 29 is moved by a bed driving device (not shown) and inserted into the treatment gauge before irradiating the ion beam from the scanning irradiation device 15, and is also attached to the scanning irradiation device 15. Positioning for irradiation is performed. The rotating drum is rotated by controlling the rotation of the motor by a gantry controller (not shown), so that the beam axis of the scanning irradiation device 15 faces the affected part of the patient 30.

  The ion beam introduced into the scanning irradiation device 15 from the inverted U-shaped beam transport device via the beam path 62 is sequentially scanned at the irradiation position by the scanning electromagnets (charged particle beam scanning devices) 5A and 5B. The affected part (for example, the site where cancer or tumor occurs) is irradiated. The irradiated ion beam releases its energy at the affected area, forming a high-dose region.

  Next, a control system 90 provided in the particle beam irradiation system according to the present embodiment will be described with reference to FIGS. 1 and 2.

  The control system 90 includes a database 110 that stores treatment plan data created by the treatment plan device 140, and an accelerator / transport system controller 40 (hereinafter referred to as an accelerator controller 40) that controls the charged electron particle beam generator 1 and the beam transport system 4. ), A scanning irradiation control device 41 (hereinafter referred to as a scanning controller 41) for controlling the scanning irradiation device 15, and a central control device 100 for controlling the accelerator controller 40 and the scanning controller 41 based on the treatment plan data read from the database 110, respectively. And have.

  The treatment plan information (patient information) for each patient stored in the database is not particularly shown, but data such as patient ID number, dose (per dose), irradiation energy, irradiation direction, irradiation position, etc. Contains.

  The central control device 100 reads the treatment plan information related to the patient 30 to be treated from the database 110 in accordance with patient identification information input from an input device such as a keyboard or a mouse. The control pattern for supplying excitation power to each electromagnet already described is determined based on the irradiation energy value in the patient-specific treatment plan information.

  A power supply control table is stored in advance in the memory in the central controller 100, and charging including the synchrotron 12 is performed according to various values (70, 80, 90,... [Mev], etc.) of irradiation energy. A supply excitation power value or a pattern for the quadrupole electromagnet 13 and the deflection electromagnet 14 in the particle beam generator 1, the quadrupole electromagnet 18 in the beam transport system 4, the deflection electromagnet 17, the quadrupole electromagnets 21 and 22, and the deflection electromagnets 23 and 24 are set in advance. ing.

  Further, the CPU in the central controller 100 uses the treatment plan information and the power supply control table, and the charged particle beam generator 1 related to the patient who is about to receive treatment and the electromagnets arranged in each beam path. Control command data (control command information) for controlling the control is created. The control command data created in this way is output to the scanning controller 41 and the accelerator controller 40.

  In the proton beam irradiation system of the present embodiment, the central control device 100, the scanning controller 41, and the accelerator controller 40 perform control in cooperation with each other based on the treatment plan information created by the treatment planning device 140. These controls will be described.

  First, the relationship between the depth of the target and the energy of the ion beam (charged particle beam) will be described. The target is an ion beam irradiation target region including the affected part, and is somewhat larger than the affected part. FIG. 3 shows an example of the relationship between the depth inside the body and the dose due to the ion beam. The charged particle beam imparts extremely large energy to the surroundings when it loses energy and stops, so it has a dose peak at its depth of arrival. This dose peak is called the Bragg peak.

  The target is irradiated with the ion beam at the position of the Bragg peak. The position of the Bragg peak changes depending on the energy of the ion beam. Therefore, the target is divided into a plurality of layers (slices) in the depth direction (the direction in which the ion beam travels in the body), and the ion beam energy is changed in accordance with the depth (each layer), thereby increasing the thickness in the depth direction. The ion beam can be uniformly irradiated over the entire target (target region) having a. Based on such a viewpoint, the treatment planning apparatus 140 determines the number of layers that divide the target region in the depth direction.

  FIG. 4 is a diagram illustrating an example of the layers determined as described above. In this example, the affected part is divided into four layers of layers 1, 2, 3, and 4 from the lowermost layer toward the body surface of the patient 30. Each layer is an example having a spread of 20 cm in the X direction and 10 cm in the Y direction. The dose distribution in FIG. 3 is a dose distribution in the depth direction in the section AA ′ in FIG. 4.

  After the number of layers is determined as described above, the treatment planning apparatus 140 determines the number of spots (irradiation positions) to be divided in the direction perpendicular to the depth direction within each layer (target cross section).

  In addition, in all spots, one spot may be divided and irradiated several times, and even if the variation in irradiation dose for each spot is within a certain range, the dose distribution is almost uniform throughout the target. The number of irradiations and the irradiation amount per target (target irradiation amount) are determined. The concept of split irradiation is detailed in Patent Document 1 (Japanese Patent No. 3681744).

  The central control device 100 reads out the treatment plan information planned as described above and stored in the database 110 and stores it in the memory. Based on the treatment plan information stored in the memory, the CPU of the central control device 100 provides information related to ion beam irradiation (number of layers, number of irradiation positions (number of spots), irradiation position in each layer, and irradiation position in each irradiation position. A target irradiation amount (set irradiation amount) and information such as current values of the scanning electromagnets 5A and 5B regarding all spots of each layer are generated and transmitted to the scanning controller 41 (first control device).

  Part of the transmitted treatment plan information is shown in FIG. Information on the X-direction position (X position) and Y-direction position (Y position) of the irradiation position (spot) for each irradiation position in the layer, the target irradiation amount (set dose) at each irradiation position, and a layer change flag Information is included and spot numbers are assigned in the order of irradiation. Furthermore, an irradiation interruption possible flag is described in each spot (0: irradiation interruption impossible, 1: irradiation interruption possible). In this embodiment, irradiation is performed in order from the deepest layer from the body surface. The target dose (set dose) at each irradiation position is an integrated dose (cumulative dose) starting from the first irradiation start on the affected area, and the central controller 100 sets the target dose for each irradiation position. Information on the target dose to be transmitted to the scanning controller 41 is generated by sequentially accumulating the individual doses. The scanning controller 41 stores these treatment plan information in a memory.

  FIG. 5 shows an example of the case where the divided irradiation is not performed. When the divided irradiation is performed, the X-direction position (X position) and the Y-direction position (Y position) of the irradiation position (spot) are further increased by the number of the divided irradiation. ) And target irradiation dose (set dose) at each irradiation position are necessary, and the treatment plan information in FIG. 5 includes such information.

  Further, the CPU of the central controller 100 transmits all the acceleration parameters of the synchrotron 12 related to all layers in the treatment plan information to the accelerator controller 40. These acceleration parameter data transmitted here are classified in advance into a plurality of acceleration patterns.

  Next, each control of the central control device 100, the scanning controller 41, and the accelerator controller 40 when performing spot scanning irradiation in the present embodiment during normal time (when there is no interruption factor) will be described with reference to FIG. FIG. 6 shows an example of a control flow for executing each control.

  First, when an irradiation start instructing device (not shown) in the treatment room is operated, the central control device 100 accordingly sets the operation i representing the layer number and the operator j representing the spot number to 1 in step 201. , And output them to the accelerator controller 40.

  The accelerator controller 40 performs initial setting accordingly, and after completion of the initial setting, in step 202, the acceleration controller 40 performs the i-th layer (i = 1 at this time) among the acceleration parameters of a plurality of patterns stored in the memory. Read and set accelerator parameters.

  In step 203, these setting parameters are output to the synchrotron 12 and the beam transport system 4, and the power source is controlled so that each electromagnet power source is excited with a predetermined current, and the high frequency power is supplied to the high frequency acceleration cavity. Is controlled to increase the high frequency power and frequency to a predetermined value.

  As described above, when the energy of the ion beam circulating in the synchrotron 12 is increased to a value determined in the treatment plan, the accelerator controller 40 proceeds to step 204 and scans via the central controller 100. An emission preparation command is output to the controller.

  In response to this emission preparation command, the scanning controller 41 (first control device), in step 205, displays the current value data stored in the memory (shown in the "X position" and "Y position" columns in FIG. 5). Data) and target dose data (data shown in the column of “target dose” in FIG. 5), current value data and target dose data of the j-th spot (j = 1 at this time) are read out. Set. Here, the scanning controller 41 controls the corresponding power supply so that the scanning electromagnets 5A and 5B are excited with the current value of the j-th spot.

  As described above, after the preparation for irradiation of the spot is completed, the scanning controller 41 outputs a beam extraction start signal to the accelerator controller 40 (third control device) via the central control device 100 in step 206. To do.

  Accordingly, the accelerator controller 40 controls the high frequency applying device 9 to emit an ion beam from the synchrotron 12 in step 207. That is, the open / close switch 92 is closed by the beam extraction start signal from the accelerator controller 40 and a high frequency is applied to the ion beam from the high frequency application electrode 93, so that the ion beam is emitted from the synchrotron 12.

  Since the scanning electromagnets 5A and 5B are excited so that the ion beam reaches the position of the j-th spot, the ion beam is irradiated to the j-th spot of the corresponding layer from the scanning irradiation device 15 in step 208. Is done.

  The j-th spot (irradiation position) is detected by the beam position monitor 6A, the beam scanning position is calculated by the scanning position measuring device 11A, and the irradiation dose to the j-th spot is detected by the dose monitor 6B. The dose value is calculated by the apparatus 11B, and the calculation result is input to the scanning controller 41.

  In step 209, the scanning controller 41 compares the set target irradiation amount with the input calculation result. When the irradiation dose to the j-th spot reaches the target irradiation amount, the scanning controller 41 proceeds to step 210. A beam extraction stop command is output to the accelerator controller 40 via the central controller 100.

  Accordingly, in step 211, the open / close switch 92 is opened via the accelerator controller 40, and the extraction of the ion beam is stopped.

  As described above, when the irradiation with respect to the first spot is completed, it is determined in step 212 whether or not it is the last spot in the layer. Since the determination is “No”, the process proceeds to step 213 and 1 is added to the spot number ( That is, the irradiation position is moved to the next spot).

  And the process of steps 205-213 is performed repeatedly. That is, the scanning electromagnets 5A and 5B sequentially move the ion beam to adjacent spots until the irradiation of all the spots of the first layer is completed (while the irradiation of the ion beam is stopped during the movement). Then, ion beam irradiation is performed (spot scanning irradiation).

  When the irradiation of all the spots on the first layer is completed, the determination is “Yes” in step 212, and the scanning controller 41 outputs a layer change command to the accelerator controller 40 via the central controller 100. .

  In addition, when performing division | segmentation irradiation, before outputting a layer change command in step 212, the following process is performed. That is, when the operator j representing the spot number is initially set to 1, it is determined whether the operator n representing the number of times of divided irradiation has reached a preset number of divisions, and the determination is “No” 1 is added to the number of times of irradiation n (that is, the divided irradiation is changed to the next number of times of irradiation), the processing of steps 205 to 213 is repeatedly performed, and the number of times of irradiation of divided irradiation is set in advance. When the number is reached, a layer change command is output to the accelerator controller 40 in step 212.

  When a layer change command is output from the scanning controller 41, the accelerator controller 40 receives it and adds 1 to the layer number i in step 214 (that is, the irradiation position is changed to the second layer). In step 215, a beam deceleration command is output to the synchrotron 12.

  The accelerator controller 40 controls the power source of each electromagnet of the synchrotron 12 according to the output of the beam deceleration command to gradually reduce the excitation current of each electromagnet. Finally, a predetermined value such as the next ion beam is used. Use an excitation current suitable for incidence. As a result, the ion beam circulating in the synchrotron 12 is decelerated.

  At this time, since the irradiation of the first layer is only completed and the determination in step 216 is “No”, the process returns to step 202 and the processing of steps 203 to 215 is repeated for the second layer. Done.

  Similarly, after the processing in steps 202 to 215 is executed for all layers, the determination in step 216 is “Yes”, and the predetermined irradiation to all spots in all layers in the affected area of the patient 30 is completed. To do. As a result, the accelerator controller 40 outputs an irradiation end signal to the CPU in step 217 to the central controller 100.

  Thus, a series of irradiation processes on the affected area of the patient 30 is completed.

  Next, the control process (spot set unit abort process) that characterizes the present embodiment will be described.

  The control system 90 according to the present embodiment monitors the abnormality of facilities and components, the beam state in the accelerator, and the like, and provides an interlock for stopping or interrupting irradiation depending on the type and level of the generated factor. Yes.

  Further, the irradiation can be manually stopped or interrupted by the operator's judgment by an irradiation stop instruction device (not shown) or an irradiation interruption instruction device (not shown) provided in the treatment room.

  Among these, this embodiment pays attention to the ion beam extraction stop method when an irradiation interruption factor occurs even during the irradiation of a certain spot or until the next spot irradiation. . FIG. 7 is a control flow of the conventional system described for comparison, and FIG. 8 is a control flow of the system of the present embodiment. Both systems normally execute processing based on the control flow described in FIG.

Of the factors for stopping and interrupting irradiation due to abnormalities in equipment and components, beam conditions in the accelerator, etc., the factor handled by the control processing of the present invention is the factor that interrupts irradiation, and it is a relatively minor factor that can continue irradiation. Limited.
FIG. 7 shows a control flow when an irradiation interruption factor occurs during irradiation of a certain spot in the conventional system.

  In the conventional system, when an irradiation interruption factor occurs during irradiation, when central processing unit 100 receives an irradiation interruption command, it first determines in step 401 whether any spot is being irradiated. This determination can be easily made by confirming whether or not the beam extraction stop command is output in step 210 of the scanning controller 41.

  When the determination result is “Yes” (that is, when an irradiation interruption factor occurs during irradiation of a certain spot), the central controller 100 stops the subsequent irradiation interruption processing until the determination becomes “No”. To do. When the determination result is “No” (that is, when an irradiation interruption factor occurs other than during irradiation of a certain spot, or an irradiation interruption factor occurs during irradiation of a certain spot, and then the irradiation to the spot ends. The central controller 100 proceeds to step 402 and outputs a beam extraction stop command and a beam irradiation stop command to the accelerator controller 40 and the scanning controller 41, respectively.

  In response to this, the scanning controller 41 interrupts the subsequent irradiation process for the j-th spot in step 403 (specifically, the process is interrupted after performing the process of step 210).

  Further, the accelerator controller 40 stops the beam emission from the synchrotron 12 in step 404, and then proceeds to step 405 to output a remaining beam deceleration command to the synchrotron 12 to output the remaining beam in the synchrotron. Decelerate.

  As described above, when an event in which irradiation has to be interrupted occurs during irradiation of a charged particle beam to a certain spot (irradiation position), the central processing unit 100 (second control device) Control of the scanning controller 41 (first control device) is continued until the irradiation amount on the spot reaches the target irradiation amount, and scanning is performed when the irradiation amount on the spot reaches the target irradiation amount in steps 401 to 404. The control of the controller 41 is interrupted and the emission of the charged particle beam from the synchrotron 12 (accelerator) is stopped.

  The central controller 100 determines in step 406 whether or not the irradiation interruption factor has been resolved and has returned to the return state. After the determination is “Yes”, the accelerator controller 40 synchronizes in step 407. A beam acceleration command is output to the TRON 12, and the power source is controlled again so that each electromagnet power source is excited with a predetermined current, and a high frequency power source for applying high frequency power to the high frequency acceleration cavity is provided. Control to increase the high frequency power and frequency to a predetermined value.

  At the same time, the accelerator controller 40 outputs a return command to the scanning controller 41. When the scanning controller 41 receives the return command, in step 408, the irradiation process for the interrupted j-th spot is resumed. To do. However, in this conventional system, since the irradiation dose to the j-th spot has reached the target irradiation amount (step 209), the irradiation process for this spot is immediately terminated, and in step 212 it is determined whether the spot is the last spot in the layer. If the determination is “No”, the process proceeds to step 213 and 1 is added to the spot number (that is, the irradiation position is moved to the next spot). Then, the process proceeds to steps 205 and 206, where the spot (irradiation position) is changed by controlling the scanning electromagnets 5A and 5B (charged particle beam scanning device) of the scanning irradiation device 15, and after this change, the synchrotron 12 (accelerator) The emission of the charged particle beam is resumed. After that, the process of each step is repeated as usual, and a series of irradiation processes on the affected part of the patient 30 is completed.

  As described above, the central processing unit 100 (second control unit) scans in steps 407 and 408 when the phenomenon that the irradiation must be interrupted after the emission of the charged particle beam is stopped in steps 402 and 404 is resolved. The control of the controller 41 (first control device) is returned, and the scanning controller 41 immediately controls the scanning electromagnets 5A and 5B (charged particle beam scanning device) in steps 213, 205 and 206 after the return. (Irradiation position) is changed, and after this change, the emission of the charged particle beam from the synchrotron 12 (accelerator) is resumed.

  By the way, in the conventional system, when an irradiation interruption factor occurs during irradiation of a certain set of spots, if the spot is being irradiated, beam irradiation (irradiation) is stopped after the irradiation of the spot is completed. Therefore, as a result, irradiation with respect to one set of spots is forcibly divided into two or more times at an intermediate stage, and as a result, the deviation of the irradiation position after resumption with respect to one set of spots. (As a factor of deviation, subtle deviations such as the state of the device and the patient can be considered.), The irradiation distribution may be disturbed.

  The feature of this embodiment is that, when an irradiation interruption factor occurs during irradiation of a set of spots, beam emission (irradiation) is not stopped, and beam emission ( By controlling to stop (irradiation), it is possible to avoid that the irradiation ends at an intermediate stage for a set of spots.

  Next, in this embodiment, the operation of the control system when an irradiation interruption factor occurs during irradiation of a certain set of spots will be described. FIG. 8 shows a control flow in the present embodiment when an irradiation interruption factor occurs during irradiation of a certain spot.

  In this embodiment, when an irradiation interruption factor occurs during irradiation, when central processing unit 100 receives an irradiation interruption command, it first determines in step 501a whether irradiation is being performed on any spot. This determination can be easily made by confirming whether the beam extraction stop command in step 210 of the scanning controller 41 is output. When the result of the determination in step 501a is “No” (that is, when irradiation is not being performed), in step 501, a determination of an irradiation interruptible spot is performed based on the information of the irradiation interruptible flag in FIG. When the determination result in step 501a is “YES” (that is, during irradiation), the central controller 100 does not execute the subsequent irradiation interruption process until “No” determination is made.

  If the result of the determination in step 501 is “No” (that is, if the spot is not a discontinuable spot), the central controller 100 does not execute the subsequent irradiation interruption process until “Yes” is determined, and step 213. The scanning controller 41 adds 1 to the spot number (that is, the irradiation position is moved to the next spot). When the determination result is “Yes” (when the irradiation of the spot at the spot where the irradiation can be interrupted is completed, that is, when all the spots of the set of spots are irradiated), the central control apparatus 100 proceeds to Step 502. The beam extraction stop command and the beam irradiation stop command are output to the accelerator controller 40 and the scanning controller 41, respectively.

  Receiving this, the scanning controller 41 interrupts the subsequent irradiation process for the j-th spot in step 503 (specifically, the process is interrupted after performing the process of step 210).

  Further, the accelerator controller 40 stops beam emission from the synchrotron 12 in step 504, and then proceeds to step 505 to output a remaining beam deceleration command to the synchrotron 12 to output the remaining beam in the synchrotron. Decelerate.

  In this way, the central processing unit 100 (second control device) determines that the event that requires the interruption of irradiation occurs in the middle of a set of spots including a spot (irradiation position) in step 501. The control of the scanning controller 41 (first control device) is continued until the target irradiation amount is reached for all spots in a set of spots. In steps 501-504, the control of the scanning controller 41 is interrupted and the synchrotron 12 ( The emission of the charged particle beam from the accelerator) is stopped.

  The central controller 100 determines in step 506 whether or not the irradiation interruption factor has been resolved and has returned to the reset state. After the determination becomes “Yes”, the accelerator controller 40 performs synchronization in step 507. A beam acceleration command is output to the TRON 12, and the power source is controlled again so that each electromagnet power source is excited with a predetermined current, and a high frequency power source for applying high frequency power to the high frequency acceleration cavity is provided. Control to increase the high frequency power and frequency to a predetermined value.

  At the same time, the accelerator controller 40 outputs a return command to the scanning controller 41. When the scanning controller 41 receives the return command, in step 508, the irradiation process for the interrupted j-th spot is resumed. To do. However, in this embodiment, since the irradiation dose to the j-th spot has reached the target irradiation amount (step 209), the irradiation process for this spot is immediately terminated, and in step 212, the final spot in the layer If the determination is “No”, the process proceeds to step 213, where 1 is added to the spot number (that is, the irradiation position is moved to the next spot). Then, the process proceeds to steps 205 and 206, where the spot (irradiation position) is changed by controlling the scanning electromagnets 5A and 5B (charged particle beam scanning device) of the scanning irradiation device 15, and after this change, the synchrotron 12 (accelerator) The emission of the charged particle beam is resumed. After that, the process of each step is repeatedly performed as usual, and a series of irradiation processes on the affected part of the patient 30 is completed.

  As described above, the central processing unit 100 (second control unit) scans in steps 507 and 508 when the event that the irradiation has to be interrupted after stopping the emission of the charged particle beam in steps 502 and 504 is resolved. The control of the controller 41 (first control device) is returned, and the scanning controller 41 immediately controls the scanning electromagnets 5A and 5B (charged particle beam scanning device) in steps 213, 205 and 206 after the return. (Irradiation position) is changed, and after this change, the emission of the charged particle beam from the synchrotron 12 (accelerator) is resumed.

  FIG. 9 and FIG. 10 are examples showing the relationship between the control pattern of the ion beam in the synchrotron 12 and the irradiation of the spot at a certain energy in the conventional system and this embodiment. In the conventional system, when the irradiation interruption factor occurs, as soon as the irradiation of the spot is completed, the emission (irradiation) is stopped and the operation immediately shifts to the deceleration operation. In this embodiment, when the irradiation interruption factor occurs, the spot When the irradiation of the entire set of spots including is completed, the emission (irradiation) is stopped and the operation proceeds to a deceleration operation).

  As described above, as a process when an irradiation interruption factor occurs, a new determination process shown in FIG. 8 (addition of the control flag of FIG. 5 to determine whether or not the spot can be interrupted) is included in the central controller 100. When the central controller 100, the accelerator controller 40, and the scanning controller 41 operate in cooperation, when an irradiation interruption factor occurs during irradiation of a certain spot in irradiation by the scanning method, As soon as the irradiation is completed, the beam emission (irradiation) is not stopped, but can be stopped when the irradiation of the entire set of spots including the spot is completed. As a result, it is possible to avoid the end of irradiation at a spot in the middle of a set of spots.

  Note that this embodiment relates to processing when an irradiation interruption event occurs in the particle beam therapy system. When an irradiation stop event occurs, the extraction ( Irradiation) is stopped, and a series of irradiation processes are stopped.

  The particle beam irradiation system of the present embodiment configured as described above has the following effects.

  Usually, the distribution of irradiation dose is to evaluate not only the dose of one spot, but also about a set of spots. In the spot in the middle of a set of spots, the irradiation is interrupted, and the cause of the interruption is eliminated. When irradiation is resumed from a spot in the middle of the set of spots, the spot position shifts depending on the state of the device and the patient, and the dose distribution is disturbed.

  FIG. 11 shows the influence on the dose distribution due to the positional deviation in the case of interruption and resumption during the irradiation of a certain spot set. For example, as shown in FIG. When it is desired to obtain a dose distribution for a set of 2 to 30 spots, the irradiation is interrupted in the middle of the set of spots of the distribution (after completion of No. 14 spot irradiation), and one spot is left open due to the position shift after resumption. When the spot irradiation is resumed, No. 1 as shown in FIG. 15 spots are not irradiated and no. 31 spots are mistakenly irradiated. On the other hand, when spot irradiation is resumed after filling one spot, No. 1 as shown in FIG. No. 14 spot is irradiated twice. 30 spots are not irradiated.

  On the other hand, in the present embodiment, when an irradiation interruption factor (a relatively mild abnormality that allows continuous irradiation) occurs during irradiation of a spot (No. 14), irradiation is performed after completion of irradiation of the spot. Irradiate all spots of a set of spots (No. 2 to 30 spots) including the spot. As a result, the planned dose distribution shown in FIG. In this way, when it is better to manage as a set of spots, the irradiation dose distribution is not disturbed by interrupting the irradiation in units of the set of spots instead of interrupting the irradiation in units of spots. , Accurate irradiation is possible.

  An example of a set of spots to which the present embodiment is preferably applied will be described. In the present embodiment, it is important how to predefine a set of spots.

  The first embodiment is an example in which a set of spots are separated in the same layer. FIG. 12 is a diagram for explaining a set of spots in the first embodiment. As shown in FIG. 12A, depending on the shape of the affected part, the affected part may be separated even in the same layer. In this case, it is better to manage each as a set of spots.

  On the other hand, as a cause of interruption of irradiation, in addition to the occurrence of an abnormality, the gate signal for respiratory synchronization control may be turned off. In the respiration synchronization control, irradiation is performed in accordance with the respiration phase when the gate signal is ON, and irradiation is stopped when the gate signal is OFF. This prevents the deviation of the spot position due to respiration and enables stable irradiation.

  However, the distribution of irradiation dose evaluates not only the dose of one spot but also a certain set of spots. If respiratory synchronous control is preferentially applied uniformly and the irradiation is interrupted when the gate signal is OFF and then the irradiation is restarted, the spot position may be shifted and the dose distribution may be disturbed. .

  FIG. 12B is a diagram illustrating an operation in which irradiation is interrupted when the gate signal is OFF, and then restarted. A black circle is a spot irradiated when the gate signal is ON, and a white circle is a spot where irradiation is stopped when the gate signal is OFF, and then irradiation is resumed when the gate signal is ON. Irradiation with respect to a set of one spot is forcibly divided into two at an intermediate stage, and as a result, there is a possibility that the irradiation dose distribution may be disturbed due to deviation of the irradiation position after resumption.

  FIG. 12C is a diagram for explaining the operation in the present embodiment. In this embodiment, when it is better to manage as a set of spots, priority is given to completing scheduled irradiation for all spots in the set of spots. That is, irradiation is continued even when the gate signal is OFF.

  Thus, by interrupting irradiation in units of a set of spots, the distribution of the irradiation dose is not disturbed, and accurate irradiation is possible. Thus, the present embodiment is suitable for use in combination with spot scanning respiratory synchronization control.

  The second embodiment is an example in which the number of spots that can be irradiated with one spill is calculated and managed as a set of spots. This is a unit that can be irradiated with one pulse of synchrotron 12 pulse operation. The target irradiation amount of each spot is calculated by the treatment planning device 140, and the number of spots that can be shot with one spill is also calculated. The set of spots is managed as one unit. When there is no problem in safety or when it is certain that the abnormality is mild, irradiation to the set of spots is continued even when the abnormality occurs.

  When applying the above-described respiratory synchronization control, the treatment planning device 140 may calculate the number of spots that can be irradiated when the gate signal is ON, and manage the set of spots as one unit.

  The third embodiment is an example in which a set of spots is overlapped. In the scanning-type particle beam irradiation system of Patent Document 1, the irradiation target is divided into a set of several spots (irradiation positions), and the number of irradiations and the irradiation amount for each irradiation are performed in advance. And irradiating each spot in multiple steps, reducing the amount of irradiation (irradiation time) for each spot, reducing variations, and more accurately detecting the actual irradiation dose A device is devised so that evaluation (evaluation of dose distribution etc.) can be performed.

  However, splitting the irradiation of one spot for all the spots multiple times leads to a prolonged treatment time, and is not efficient in terms of system operation.

  In order to solve the above problem, an irradiation method for overlapping a set of spots has been proposed. FIG. 13 is a diagram for explaining a set of spots in the third embodiment.

  For example, as shown in the upper part of FIG. Plan to obtain dose distribution for a set of 2-35 spots. At this time, no. A set of 2 to 23 spots is defined as a first set. A set of 15 to 35 spots is managed as a second set. The first set is set so that the dose increases monotonically from the 2nd to the 9th spot, the dose is a constant value from the 9th to the 14th spot, and the dose decreases monotonously from the 14th to the 23rd spot, and becomes a trapezoidal shape shown in the figure. Has been. The second set is set so that the dose increases monotonically from the 15th to the 24th spot, the dose is a constant value from the 24th to the 28th spot, and the dose decreases monotonically from the 28th to the 35th spot, and becomes a trapezoidal shape shown in the figure. Has been. Further, for the first set and the second set, No. Overlapping is provided at 15 to 23 spots. Irradiation is performed on the first set and the second set so as to obtain dose distributions as shown in the lower part of FIG. As a result, the planned dose distribution can be obtained as shown in the upper part of FIG.

  As a result, the first set and the second set are each managed as one unit of the set of spots without irradiating a single spot multiple times for all spots. It leads to shortening and becomes efficient in terms of system operation.

  The effect when this embodiment is applied to the third embodiment will be described. In the present embodiment, each of the first set and the second set is managed as one unit of a set of spots, and priority is given to completing scheduled irradiation for all spots in the set of spots. That is, even when a relatively mild abnormality occurs during the irradiation of the first set of spots, the irradiation of the first set is continued. After the irradiation with respect to the first set (No. 2 to 23 spots) is completed, the irradiation is stopped, and when the irradiation interruption event is resolved, the irradiation is restarted from the head of the second set (No. 15 to 35 spots). Even when a relatively mild abnormality occurs during irradiation of the second set of spots, the irradiation of the second set is continued in the same manner.

  The upper part of FIG. 13 (b) is a diagram for explaining a case where a positional deviation occurs at the time of interruption and resumption, and the position is shifted by one spot, and the lower part of FIG. 13 (b) is a diagram for explaining the effect of this embodiment. It is. Irradiation to the first set (Nos. 2 to 23 spots) was done as planned, but the position to be irradiated to the second set (Nos. 15 to 35 spots) was shifted by one spot due to positional misalignment. No. It is assumed that 14 to 34 spots are irradiated. However, when the set of spots, which is the combination of the first set and the second set, is evaluated, the result is as shown in the lower part of FIG. 13B, and compared with the planned dose distribution in the upper part of FIG. No. 35 spot was not irradiated and no. It can be seen that only 14 to 23 spots are slightly irradiated and there is little influence of positional deviation.

  The upper part of FIG. 13 (c) is a diagram for explaining a case where a positional deviation occurs at the time of interruption and resumption, and the position is shifted after one spot, and the lower part of FIG. 13 (c) is a diagram for explaining the effect of this embodiment. is there. Irradiation to the first set (Nos. 2 to 23 spots) was done as planned, but the position to be irradiated to the second set (Nos. 15 to 35 spots) was shifted by one spot due to positional misalignment. No. It is assumed that 16 to 36 spots are irradiated. However, when the set of spots, which is the combination of the first set and the second set, is evaluated, it becomes as shown in the lower part of FIG. 13 (c), and compared with the planned dose distribution in the upper part of FIG. No. 36 spot was mistakenly irradiated and no. It can be seen that only 15 to 24 spots are irradiated with slightly less eyes, and the influence of positional deviation is small.

  Thereby, the efficiency of the system operation is improved, and the irradiation is interrupted in units of a set of spots, so that the irradiation dose distribution is not disturbed and the irradiation can be performed with high accuracy. Thus, this embodiment is suitable for use in combination with the irradiation method shown in the third example.

  However, in this embodiment, even when an abnormality occurs, irradiation can be continued depending on the type and level of the factor that has occurred. From the viewpoint of patient and operator safety, the types of factors that can continue irradiation The level selection is very important.

  The ion beam irradiation by spot scanning described above can be applied to a proton beam irradiation system using a cyclotron as an accelerator.

DESCRIPTION OF SYMBOLS 1 ... Charged particle beam generator 4 ... Beam transport system 5A, 5B ... Scanning electromagnet (charged particle beam scanning device)
6A ... Scanning position monitor (irradiation dose detection device)
6B ... Dose monitor (irradiation amount detection device)
7A ... Scanning magnet power supply (X direction)
7B: Scanning magnet power supply (Y direction)
8 ... Scanning magnet power supply control device 9 ... High frequency application devices 11A, 11B ... Scanning position measuring device 12 ... Synchrotron (accelerator)
DESCRIPTION OF SYMBOLS 15 ... Scanning irradiation apparatus 40 ... Accelerator and transport system controller 41 ... Scanning controller (1st control apparatus)
42 ... Power supply control device 90 ... Control system (control device)
91 ... high frequency power source 92 ... open / close switch 93 ... high frequency application electrode 100 ... central control device (second control device)
140 ... Treatment planning device

  The feature of the present invention for achieving the above-described object is that it has an accelerator for emitting a charged particle beam and a charged particle beam scanning device, and irradiates an irradiation spot to be irradiated with the charged particle beam emitted from the accelerator. The irradiation spot of the charged particle beam is changed while the irradiation of the charged particle beam is stopped and the irradiation of the charged particle beam is restarted after the change of the irradiation spot. And a control device that irradiates the irradiation target, wherein the control device is a spot that can be interrupted in advance in each of a plurality of layers obtained by dividing the irradiation target in the depth direction. And when the charged particle beam irradiation interruption factor occurs, the irradiation of the charged particle beam to the irradiation interruptable spot is completed. The irradiation spot is not executed until the irradiation spot is updated, and the irradiation spot is updated and the irradiation with the charged particle beam is continued. It is to execute the irradiation interruption process at the time of completion.

Claims (8)

An accelerator that emits a charged particle beam;
An irradiation device that has a charged particle beam scanning device and irradiates an irradiation spot to be irradiated with the charged particle beam emitted from the accelerator;
If an event that requires interruption of irradiation occurs during irradiation of the charged particle beam to the irradiation spot, the irradiation spot at that time is not immediately stopped without stopping the emission of the charged particle beam from the accelerator. A particle beam irradiation system comprising: a control device that stops emission of the charged particle beam from the accelerator at the time when irradiation of all spots belonging to a predefined set of spots is completed. The particle beam irradiation system according to claim 1,
The controller immediately changes the irradiation spot when the event that the irradiation has to be interrupted is resolved after the emission of the charged particle beam is stopped, and continues the extraction of the charged particle beam from the accelerator. A particle beam irradiation system which restarts from the head irradiation spot of a set of spots. An accelerator that emits a charged particle beam;
An irradiation device that has a charged particle beam scanning device and irradiates an irradiation spot to be irradiated with the charged particle beam emitted from the accelerator;
When the irradiation amount to the irradiation spot reaches the target irradiation amount, the charged particle beam scanning device is controlled in a state where the emission of the charged particle beam from the accelerator is stopped and the output of the charged particle beam is stopped. Changing the irradiation spot to the next spot, and starting the output of the charged particle beam from the accelerator after changing the irradiation spot;
When an event that requires interruption of irradiation occurs during irradiation of the charged particle beam to the irradiation spot, the control of the first controller is continued until the irradiation amount to the irradiation spot reaches the target irradiation amount. Then, when the irradiation amount to the irradiation spot reaches the target irradiation amount, the control to the next spot of the first control device is continued, and all spots belonging to a predefined set of spots including these irradiation spots A particle beam irradiation system comprising: a second control device that interrupts the control of the first control device and stops the emission of the charged particle beam from the accelerator when the irradiation is completed. In the particle beam irradiation system according to claim 3,
The second control device returns the control of the first control device when the event that the irradiation must be interrupted after the emission of the charged particle beam is stopped,
The first control means changes the irradiation spot by controlling the charged particle beam scanning device immediately after returning, and after this change, the charged particle beam is emitted from the accelerator to the head of the next set of spots. The particle beam irradiation system is characterized by restarting from the irradiation spot. In a method for controlling a particle beam irradiation system, comprising: an accelerator that emits a charged particle beam; and an irradiation device that has a charged particle beam scanning device and irradiates an irradiation spot to be irradiated with the charged particle beam emitted from the accelerator. ,
If an event that requires interruption of irradiation occurs during irradiation of the charged particle beam to the irradiation spot, the irradiation spot at that time is not immediately stopped without stopping the emission of the charged particle beam from the accelerator. A method for controlling a particle beam irradiation system, comprising: stopping emission of the charged particle beam from the accelerator at a time point when irradiation of all spots belonging to a predefined set of spots is completed. In the control method of the particle beam irradiation system according to claim 5,
When the event that the irradiation has to be interrupted is resolved after stopping the emission of the charged particle beam, the irradiation spot is immediately changed, and the emission of the charged particle beam from the accelerator is changed to the next set of spots. A method for controlling a particle beam irradiation system, wherein the irradiation is resumed from the first irradiation spot. In a method for controlling a particle beam irradiation system, comprising: an accelerator that emits a charged particle beam; and an irradiation device that has a charged particle beam scanning device and irradiates an irradiation spot to be irradiated with the charged particle beam emitted from the accelerator. ,
When the irradiation amount to the irradiation spot reaches the target irradiation amount, the charged particle beam scanning device is controlled in a state where the emission of the charged particle beam from the accelerator is stopped and the output of the charged particle beam is stopped. Changing the irradiation spot to the next spot, and starting the output of the charged particle beam from the accelerator after changing the irradiation spot;
If an event that requires interruption of irradiation occurs during irradiation of the charged particle beam to the irradiation spot, the control of the first procedure is continued until the irradiation amount to the irradiation spot reaches the target irradiation amount. When the irradiation amount to the irradiation spot reaches the target irradiation amount, the control of the first procedure is continued at the next spot, and irradiation is performed on all spots to which a predefined set of spots including these irradiation spots belong. A control method for a particle beam irradiation system, comprising: a second procedure that interrupts the control of the first procedure when it is completed and stops the emission of the charged particle beam from the accelerator. In the particle beam irradiation system according to claim 7,
The second procedure returns the control of the first procedure when the event that the irradiation must be interrupted after the emission of the charged particle beam is stopped,
In the first procedure, immediately after returning, the irradiation spot is changed by controlling the charged particle beam scanning apparatus, and after the change, the emission of the charged particle beam from the accelerator is changed to the head of the next set of spots. A method of controlling a particle beam irradiation system, wherein the method restarts from an irradiation spot.

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