JP2019092985A - Electromagnet adjustment method of beam transport system - Google Patents

Abstract

To obtain an electromagnet adjustment method of a beam transport system, the method enabling the start work of a particle beam therapy apparatus to be performed within a short period of time than before.SOLUTION: The electromagnet adjustment method of a beam transport system comprises: a constant dose control procedure of calculating an emission dose value (dosimeter measured value Dm) of a charged particle beam 28 based on dose measurement information sig2 measured with dosimetry equipment 9 arranged in a beam transport system 3, and controlling an accelerator by an emission amount control device (RFKO control device 5) so that the emission dose value (dosimeter measured value Dm) of the charged particle beam 28 falls within a dose tolerance including a target value (dose target value Di); and a current pattern determination procedure of calculating a beam position of the beam 28 based on position measurement information sig1 measured with position measurement equipment 8 arranged in the beam transport system 3 by using the beam 28 controlled in the constant dose control procedure, and determining a current pattern Ip1 of an electromagnet 7 of the upstream side using the arrangement position of the position measurement equipment 8 based on the beam position.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a particle beam therapy apparatus for treating a diseased part such as cancer by irradiating a charged particle beam such as a proton beam or a carbon ion beam to a beam, and a beam transport system for transporting the charged particle beam to an irradiation apparatus installed in an irradiation room. The invention relates to a method of adjusting an electromagnet of

  Patent Document 1 discloses a first beam transport system for transporting charged particle beams emitted from an accelerator of a charged particle beam generator to irradiation devices installed in four treatment rooms, and a branch from the first beam transport system A charged particle beam irradiation system is disclosed which comprises four second beam transport systems and a fast steerer arrangement. The high-speed steerer device is disposed in the middle of the first beam transport system, and includes a high-speed steerer electromagnet, a dosimeter, and a damper. The charged particle beam irradiation system (particle beam therapy device) of Patent Document 1 charges the irradiation device. The beam intensity (dose) of the charged particle beam was measured without transporting the particle beam, and the beam intensity (dose) of the charged particle beam emitted from the accelerator was adjusted.

  When taking out a charged particle beam from a synchrotron which is an accelerator, the RF KO (RF-knockout) method may be used. In particle radiotherapy apparatus equipped with a synchrotron, the irradiation target such as a diseased part is irradiated with a charged particle beam of constant intensity (constant dose) emitted by RFKO method applying spill feedback (see Non-patent document 1) There is a device configured as follows. In the case of a particle beam therapy system to which spill feedback is applied, after installation and assembly of the beam transport system and the irradiation apparatus are completed, feedback is made to the RFKO controller using the dose measured by the dose monitor of the irradiation apparatus. I needed it. For this reason, the electromagnet adjustment of the beam transport system and the installation and assembly of the equipment of the irradiation apparatus can not be performed at the same time, and the work of setting up the particle beam therapy apparatus has been long.

JP, 2009-148473, A (0021 stage-0046 stage, FIG. 1, FIG. 2)

“Development of beam current control system in RF-knockout slow extraction”, Nuclear Instruments and Methods in Physics Research B 269 (2011) 2915-2918

  The charged particle beam irradiation system (particle beam therapy apparatus) disclosed in Patent Document 1 uses a high-speed steerer apparatus disposed in the middle of the first beam transport system to transmit a charged particle beam without transporting the charged particle beam to the irradiation apparatus. The beam intensity (dose) was measured to adjust the beam intensity (dose) of the charged particle beam emitted from the accelerator. However, when spill feedback is applied to the charged particle beam irradiation system of Patent Document 1, after the installation and assembly of the beam transport system and the irradiation apparatus are completed, the dose measured by the dose monitor of the irradiation apparatus is used. Needs to be fed back to the RFKO controller, and it is not possible to simultaneously adjust the electromagnet of the beam transport system and the installation and there were.

  The present invention has been made to solve the above-mentioned problems, and even if the assembly of the equipment of the irradiation apparatus is not completed, the electromagnet adjustment of the beam transport system can be performed, and the particle beam therapy system is set up more than before. It is an object of the present invention to obtain a method of adjusting an electromagnet of a beam transport system which can perform the work in a short time.

  The electromagnet adjustment method of a beam transport system according to the present invention is an electromagnet adjustment method of a beam transport system for adjusting an electromagnet of a beam transport system for transporting a charged particle beam emitted from an accelerator to an irradiation apparatus, and arranged in the beam transport system The radiation dose value of the charged particle beam is calculated based on the dosimetry information measured by the selected dose measurement device, and the radiation amount control device is set so that the radiation dose value of the charged particle beam falls within the dose tolerance range including the target value. Charged particle based on position measurement information measured by a position measuring instrument disposed in a beam transport system using a constant dose control procedure for controlling an accelerator by the above and a charged particle beam controlled by a constant dose control procedure A current pattern determination procedure of calculating the beam position of the beam and determining the current pattern of the electromagnet upstream of the arrangement position of the position measurement device based on the beam position; Including. The current pattern determination procedure changes the current pattern of the electromagnet so that the beam position of the charged particle beam falls within the design range when the beam position of the charged particle beam exceeds the design range.

  The electromagnet adjustment method of the beam transport system according to the present invention is characterized in that the output dose value of the charged particle beam falls within the dose allowable range including the target value based on the dosimetry information measured by the dose measuring device arranged in the beam transport system. After adjustment, the beam transport system's electromagnets are adjusted, so even if the equipment of the irradiation system has not been completely assembled, the beam transport system's electromagnets can be adjusted, and the particle beam therapy system can be started more quickly than before. You can do it in the meantime.

It is a schematic block diagram of a particle beam therapy system which applies an electromagnet adjustment method of a beam transportation system by Embodiment 1 of the present invention. It is a figure which shows the structure of the electromagnet adjustment apparatus of FIG. It is a figure which shows the structure of the RFKO control apparatus of FIG. It is a figure which shows the signal characteristic of original signal wi1 of FIG. 3, and wi2. It is a figure which shows the structure of the dose signal processing apparatus of FIG. It is a figure which shows the structure of the image processing apparatus of FIG. It is a figure which shows the example of the camera image input into the image processing apparatus of FIG. It is a figure which shows the example of beam distribution which the image processing apparatus of FIG. 2 produced | generated. It is a figure which shows the electromagnet and port for measurement of the beam transport system of FIG. It is a figure which shows the port of FIG. It is a figure which shows the 1st example of the order which measures a beam position. It is a figure which shows the 2nd example of the order which measures a beam position. It is a flowchart explaining the electromagnet adjustment method of the beam transport system by Embodiment 1 of this invention. It is a flowchart explaining the electromagnet adjustment method of the other beam transport system by Embodiment 1 of this invention. It is a figure explaining the starting period of the particle beam therapy apparatus in, when the electromagnet adjustment method of the beam transport system by Embodiment 1 of this invention is applied. It is a figure which shows the structure of the electromagnet adjustment apparatus by Embodiment 2 of this invention. It is a figure which shows the structure of the electromagnet adjustment apparatus by Embodiment 3 of this invention. It is a figure which shows the structure of the dose signal processing apparatus of FIG. It is a figure which shows the monitor current of the position monitor of FIG. It is a figure which shows the structure of the position signal processing apparatus of FIG. It is a figure which shows the structure of the electromagnet adjustment apparatus by Embodiment 4 of this invention. It is a schematic block diagram of a particle beam therapy system which applies an electromagnet adjustment method of a beam transportation system by Embodiment 5 of the present invention. It is a figure which shows the structure of the position measurement apparatus in the electromagnet adjustment apparatus of FIG. 22, and a setting parameter production | generation apparatus. It is a figure which shows the structure of the RFKO control apparatus of FIG. It is a figure which shows the hardware constitutions which implement | achieve the function of a computer.

Embodiment 1
FIG. 1 is a schematic block diagram of a particle beam therapy system to which a method of adjusting an electromagnet of a beam transport system according to a first embodiment of the present invention is applied. FIG. 2 is a view showing the configuration of the electromagnet adjustment device of FIG. 1, and FIG. 3 is a view showing the configuration of the RFKO control device of FIG. FIG. 4 is a diagram showing the signal characteristics of the original signals wi1 and wi2 of FIG. 3, and FIG. 5 is a diagram showing the configuration of the dose signal processing apparatus of FIG. FIG. 6 is a diagram showing the configuration of the image processing apparatus of FIG. FIG. 7 is a view showing an example of a camera image input to the image processing apparatus of FIG. 2, and FIG. 8 is a view showing an example of beam distribution generated by the image processing apparatus of FIG. FIG. 9 is a view showing an electromagnet and a port for measurement of the beam transport system of FIG. 1, and FIG. 10 is a view showing the port of FIG. FIG. 11 is a view showing a first example of the order of measuring beam positions, and FIG. 12 is a view showing a second example of the order of measuring beam positions. FIG. 13 is a flow chart for explaining an electromagnet adjustment method of a beam transportation system according to the first embodiment of the present invention, and FIG. 14 is a flow chart for explaining another electromagnet adjustment method of a beam transportation system according to the first embodiment of the present invention is there. FIG. 15 is a diagram for explaining the start-up period of the particle beam therapy system in the case of applying the electromagnet adjustment method of the beam transport system according to the first embodiment of the present invention.

  A particle beam therapy system 1 to which an electromagnet adjustment method of a beam transport system according to a first embodiment of the present invention is applied will be described. The particle beam therapy system 1 is transported by an accelerator 2 which is a synchrotron, a beam transport system 3 which transports a charged particle beam 28 accelerated to a required energy by the accelerator 2 to an irradiation apparatus 4, and a beam transport system 3 And an irradiation device 4 for irradiating the charged particle beam 28 to an affected part (irradiation target) of a patient. In addition, the particle beam therapy system 1 is generated by the RFKO control device (emission amount control device) 5 that controls the charged particle beam 28 to be extracted from the accelerator 2 using the radio frequency knockout (RFKO) method, and the RFKO control device 5 The amplifier 6 amplifies the control signal siga (see FIG. 3) and outputs the amplified signal to the RFKO electrode (adjustment electrode) 19 of the accelerator 2. In the particle beam therapy system 1 for which the start-up operation has been completed, the dose of the charged particle beam 28 measured by a dose monitor (not shown) disposed in the irradiation device 4, for example, is input to the RFKO controller 5. The RFKO controller 5 controls the charged particle beam 28 having a constant intensity (constant dose) to be emitted from the accelerator 2 based on the input dose (feedback dose). More specifically, the RFKO controller 5 controls the charged particle beam 28 of constant intensity (constant dose) to be an accelerator 2 so that the value of the input dose (feedback dose) falls within the dose tolerance range including the target value. Control to be emitted from The RFKO electrode 19 adjusts the dose of the charged particle beam 28 emitted from the accelerator 2.

  The schematic configuration of the particle beam therapy system 1 shown in FIG. 1 shows the schematic configuration during the start-up operation. An accelerator 2, a beam transport system 3, and an amplifier 6 are disposed in the accelerator chamber 12, an irradiation device 4 is disposed in the irradiation chamber 13, and an RFKO controller 5 is disposed in the power supply chamber 14. The beam transport system 3 includes an electromagnet 7, a vacuum duct 29, an electromagnet power supply 11 and the like. The electromagnet adjustment device 10 executing the electromagnet adjustment method of the beam transport system generates position measurement information sig1 which is measured position information of the charged particle beam 28 traveling through the vacuum duct 29 of the beam transport system 3. And the setting parameter information data1 including the current pattern of the electromagnet power supply 11 controlling the electromagnet 7 to be adjusted and the dosimetry device 9 generating the dosimetry information sig2 which is the measured dose information of the charged particle beam 28 And a setting parameter generation device 15. The electromagnet power supply 11 outputs a current pattern Ip1, which is a control command, to the electromagnet 7 based on the setting parameter information data1. The setting parameter generation device 15 outputs, to the RFKO control device 5, the dose value information sig3 in which the dose measurement information sig2 is converted into a digital signal when the adjustment operation of the electromagnet 7 is performed.

  As shown in FIG. 2, the setting parameter generation device 15 includes a dose signal processing device 25, an image processing device 27, and a current pattern setting device 31. The position measurement device 8 includes, for example, a screen monitor 22 and a camera 24. The dose measuring device 9 includes, for example, a dose monitor 21 and a high voltage generator 26. The screen monitor 22 is a fluorescent screen, and the screen monitor 22 emits light when the charged particle beam 28 strikes, and the light emission 56 is photographed by the camera 24. The image information including the light emission 56 of the charged particle beam 28 captured by the camera 24 is position measurement information sig1 used to calculate the beam position of the charged particle beam 28. The dose monitor 21 is, for example, a transmission multi-wire monitor. The dose monitor 21 detects the current of ions in which the enclosed gas such as argon or nitrogen is ionized by the passage of the charged particle beam 28, with the high voltage generated by the high voltage generator 26 using the applied wire. The minute current detected by the dose monitor 21 is dose measurement information sig2. That is, the dose measurement information sig2 is current information. The dose measurement information sig2 detected by the dose monitor 21 is output to the dose signal processing device 25.

  The dose signal processing device 25 includes, for example, a current-voltage converter 51, an amplifier 52, an AD converter 53, a transmission format converter 54, and an optical signal converter 55, as shown in FIG. The current-voltage converter 51 converts the dose measurement information sig2, which is a minute analog signal input thereto, into a voltage V1. The amplifier 52 amplifies the voltage V1 to the voltage V2. The AD converter 53 analog-digital converts (AD converts) the voltage V2 to generate a digital signal dt1. The transmission format converter 54 matches the digital signal dt1 with the transmission format, that is, converts the transmission format into a transmission signal fdt1. The optical signal converter 55 converts the transmission signal fdt1 into an optical signal to generate dose value information sig3. The transmission signal fdt1 and the dose value information sig3 include, in addition to the dose information, an enable signal defined in a transmission format.

  The image processing device 27 includes, for example, a computer 57, a display device 58, and a storage device 59 as shown in FIG. When adjusting the electromagnet 7 of the beam transport system 3, the downstream side of the screen monitor 22 (side of the irradiation device 4) prevents the residual beam transmitted through the screen monitor 22 from proceeding downstream, ie, charging A beam damper 23 for blocking the particle beam 28 is also arranged in the vacuum duct 29 of the beam transport system 3. The vacuum duct 29 is provided with a window 30 for photographing the screen monitor 22. The camera 24 captures light emission 56 by the charged particle beam 28 appearing on the screen monitor 22, and outputs position measurement information sig 1 to the computer 57. The calculator 57 generates a camera image 60 based on the position measurement information sig1. The computer 57 calculates the beam position (coordinates of the center), the beam size (spread), and the beam distribution 61 of the charged particle beam 28 from the luminance information of the camera image 60. The beam position, beam size, and beam distribution 61 are displayed on the display unit 58 and stored in the storage unit 59. The display device 58 is a display or the like, and the storage device 59 is a memory, a hard disk (HDD) or the like. The calculator 57 also outputs position information sig4 to the current pattern setting device 31. The position information sig 4 is the beam position (coordinates of center) of the charged particle beam 28, the beam size (spread), and the beam distribution 61.

  In the camera image 60 shown in FIG. 7, for example, light and shade of luminance is shown in each rectangular area divided into small rectangular areas. The beam distribution 61 shown in FIG. 8 is an example in which the luminance of each rectangular area is numerically data. The rectangular area is an area divided at the position in the x direction and the position in the y direction. The traveling direction of the charged particle beam 28 is the z direction, the x direction is perpendicular to the z direction, and the y direction is perpendicular to the x direction and the z direction. A region indicated by C in the camera image 60 and the beam distribution 61 is a region where the beam brightness is the highest, and the beam position exists in this region C. Although FIG. 7 and FIG. 8 show 5 × 5 areas, they are actually divided into a larger number of rectangular areas than this.

  As shown in FIG. 3, the RFKO controller 5 includes a fundamental wave signal generator 45, a feedback controller 46, and an AM (amplitude modulation) modulator 37 which is a control signal generator. The fundamental wave signal generation unit 45 includes an original signal generator 32, three signal generators 33, 34, 35, and a three-wave combiner 36. The feedback control unit 46 includes an input unit 44 and a PI control circuit 49. The original signal generator 32 generates an original signal wi1 having the characteristic of the signal characteristic 47 shown in FIG. 4, an original signal wi2 having the characteristic of the signal characteristic 48 shown in FIG. 4, and an original signal wi3 having a constant frequency. The vertical axis of the characteristic of FIG. 4 is frequency, and the horizontal axis is time. The signal characteristic 47 is a signal characteristic in which the frequency periodically changes in a triangular shape, and the signal characteristic 48 is a signal characteristic in which the signal characteristic 47 is shifted by a half cycle. FIG. 4 shows an example in which the frequency change period is 1 ms.

  The signal generator 33 generates a frequency-modulated basic signal w1 from the original signal wi1, the signal generator 34 generates a frequency-modulated basic signal w2 from the original signal wi2, and the signal generator 35 generates a frequency from the original signal wi3. Generate a modulated basic signal w3. The three-wave combiner 36 combines the three basic signals w1, w2, w3 to generate a fundamental wave signal wa. The AM modulator 37 generates a control signal siga in which the fundamental wave signal wa is AM-modulated based on the modulation control signal sigc generated by the feedback control unit 46. The control signal siga is output to the amplifier 6.

  The input unit 44 of the feedback control unit 46 generates a dose measurement value Dm based on the dose value information sig3. The dose target value Di is a predetermined target value of the dose of the charged particle beam 28 output by the accelerator 2. The PI control circuit 49 executes PI control (proportional integral control) based on the dose measurement value Dm and the dose target value Di to generate a modulation control signal sigc. When executing PI control, the PI control circuit 49 calculates a dose difference which is a difference between the dose target value Di and the dose measurement value Dm, and based on the dose difference, the dose target value Di, and the dose measurement value Dm. A modulation control signal sigc is generated.

  The position information sig 4 generated by the computer 57 of the image processing device 27 is output to the current pattern setting device 31. The current pattern setting device 31 generates setting parameter information data1 including the current pattern Ip1 of the electromagnet power supply 11 according to the instruction of the operator based on the position information sig4. The setting parameter information data1 includes the type of charged particles of the charged particle beam 28, the energy, the type of charged particles, and the association information of the energy and the current pattern Ip1. FIG. 2 shows an example in which the setting parameter information data1 generated by the current pattern setting device 31 is stored in the memory in the control device of the electromagnet power supply 11. When the rising of the particle beam therapy system 1 is completed and the charged particle beam 28 is irradiated, the current pattern Ip1 corresponding to the type and energy of the charged particle is selected, and the electromagnet 7 is excited by the current pattern Ip1. . The setting parameter information data 1 may be stored in a storage device (HDD, memory, etc.) of a control device (control computer) (not shown) of the beam transport system 3. When one type of particle beam therapy system does not change the type of charged particles, the type of charged particles may not be included in the setting parameter information data1. When a plurality of particle beam therapy apparatuses are installed at the treatment facility, management classified into the type of charged particles of the setting parameter information data 1 can be easily performed based on the type of charged particles.

  The electromagnet adjustment method of the beam transportation system according to the first embodiment of the present invention will be described with reference to FIGS. There are a plurality of electromagnets 7 to be adjusted in the beam transport system 3. For example, as shown in FIG. 9, a deflection electromagnet for deflecting the charged particle beam 28, a quadrupole electromagnet for focusing or diverging the charged particle beam 28, a charged particle beam 28 It is a hexapole electromagnet etc. which corrects an aberration. In FIG. 9, two deflection electromagnets 62a and 62b, five quadrupole electromagnets 63a, 63b, 63c, 63d and 63e, and one hexapole electromagnet 64 are shown. Further, FIG. 9 shows five ports 65a, 65b, 65c, 65d and 65e. As shown in FIG. 10, the port 65 is a cylindrical container in which the dose monitor 21 for detecting the dose of the charged particle beam 28, the screen monitor 22 for detecting the beam position, and the beam damper 23 are taken in and out. The port code generally uses 65, and 65a to 65e are used in the case of distinction. FIG. 10 also shows the dose monitor 21a in a state in which the dose monitor 21 inserted into the vacuum duct 29 is retracted. Similarly, the screen monitor 22 inserted into the vacuum duct 29, the screen monitor 22a with the beam damper 23 retracted, and the beam damper 23a are also shown. Although FIG. 10 shows one port where the dose monitor 21, screen monitor 22 and beam damper 23 can be simultaneously put in and out at each measurement point of the beam transport system 3, the beam transport system 3 has dose monitor 21 at each measurement point, screen monitor 22, The beam damper 23 may have ports that can be taken in and out individually, that is, three ports. FIG. 10 shows an example in which the port 65 is provided with the window 30 through which the light 56 from the screen monitor 22 passes.

  The current pattern Ip1 of the electromagnet 7 (a deflection electromagnet, a quadrupole electromagnet, a hexapole electromagnet) of the beam transport system 3 is set for each energy of the charged particle beam 28. Therefore, the energy of the charged particle beam 28, the dose of the charged particle beam 28, and the order of measurement points for measuring the beam position can be considered in plural. In FIG. 11, the measurement point is changed from the upstream side to the downstream side for one energy to adjust the electromagnet 7, and after the adjustment at all the measurement points is finished, the next energy is changed to change the electromagnet 7 An example (first example) of performing adjustment of In FIG. 12, the energy is changed for one measurement point to adjust the electromagnet 7, and after adjustment with all the energy is finished, the next (downstream) measurement point is changed to change the electromagnet 7 The example (2nd example) which adjusts is shown. The current pattern Ip1 can be expressed as a current pattern Ip1 (t) because the current value changes according to the time t during irradiation of the charged particle beam 28, ie, the time t emitted from the accelerator 2.

  The measurement points P1, P2, P3, P4, and P5 shown in FIGS. 11 and 12 correspond to the positions of the ports 65a, 65b, 65c, 65d, and 65e in FIG. 9, respectively. 11 and 12 show four energies E1, E2, E3 and E4. The number of energy is not limited to four. As for the reference numerals of measurement points, P is used in a general manner, and P1 to P5 are used in the case of describing separately.

  The flowchart of the electromagnet adjustment method of the beam transport system shown in FIG. 13 corresponds to the measurement order of the first example of FIG. 11, and the flowchart of the electromagnet adjustment method of the beam transport system shown in FIG. It corresponds to the measurement order of the example. The flowchart of FIG. 13 will be described. First, the accelerator 2 is set to emit a charged particle beam of the first energy E1. In addition, at the first port 65 located downstream closest to the electromagnet 7 to be measured, the dose monitor 21, the screen monitor 22, and the beam damper 23 are inserted in advance by the operator into the vacuum duct 29 (detector insertion procedure). At step ST01, the position of the charged particle beam 28 emitted from the accelerator 2 is measured at the measurement point P on the downstream side of the electromagnet (measurement object electromagnet) 7 to be measured (beam position measurement procedure). The beam position measurement procedure includes multiple procedures. First, the accelerator 2 emits the charged particle beam 28 according to the instruction of the operator (a beam emission start procedure). Based on dose value information sig3 generated by the dose signal processing unit 25 of the setting parameter generation unit 15, the dose value (emission dose value) of the charged particle beam 28 emitted from the accelerator 2 is detected by the dose monitor 21. The RFKO controller 5 sets the output dose value of the accelerator 2 so that the dose value of the charged particle beam 28 falls within the dose tolerance range including the preset target value, that is, the dose value becomes a constant dose value. Control (constant dose control procedure). Note that the allowable dose range is set in advance. After the dose value of the charged particle beam 28 emitted from the accelerator 2 becomes a constant dose value, the position (beam position) of the charged particle beam 28 is measured (measurement procedure). In the beam position measurement procedure, the image processing device 27 calculates the beam position based on the position measurement information sig1 at regular intervals. More specifically, the calculator 57 of the image processing device 27 of the setting parameter generation device 15 calculates the beam position based on the position measurement information sig1.

  When the time (the settling time) at which the dose value of the charged particle beam 28 emitted from the accelerator 2 becomes a fixed dose value is known in advance, the position of the charged particle beam 28 after the settling time has elapsed ( The beam position may be measured. Optionally, the position of the charged particle beam 28 also uses the beam position or the beam position of the charged particle beam 28.

  In step ST02, it is determined whether the beam position is within the design range (beam position determination procedure). The calculator 57 of the image processing device 27 of the setting parameter generation device 15 displays on the display device 58 the determination result as to whether the beam position and the beam position are within the design range. In step ST02, when the beam position is within the design range, the process proceeds to step ST05, and when the beam position is not within the design range, the process proceeds to step ST03.

  In step ST05, the operator determines whether or not the measurement point P remains (a measurement point confirmation procedure). In step ST05, when measurement point P remains, it progresses to step ST06, and when measurement point P does not remain, it progresses to step ST07. In step ST06, the operator stops the emission of the charged particle beam 28 from the accelerator 2, and the dose monitor 21, the screen monitor 22, and the beam damper 23 at the port (first port 65) of the measurement point where the measurement is completed. The vacuum duct 29 is evacuated. After that, the operator inserts the dose monitor 21, the screen monitor 22, and the beam damper 23 into the vacuum duct 29 from the second port 65 located downstream closest to the electromagnet 7 to be measured next (measurement point changing procedure) . Returning to step ST01, the position of the charged particle beam 28 emitted from the accelerator 2 is measured at the next measurement point P on the downstream side.

  In step ST03, the operator operates the current pattern setting device 31 of the setting parameter generation device 15 so that the measurement on the upstream side of the measurement point P so that the beam position of the charged particle beam 28 falls within the design range. The current pattern Ip1 of the target electromagnet (measurement target electromagnet) 7 is changed (current pattern change procedure). Thereafter, in step ST04, the position (beam position) of the charged particle beam 28 is measured (beam position remeasurement procedure). The beam position remeasurement procedure is the same operation as the beam position measurement procedure. Thereafter, the process returns to step ST02, and the beam position determination procedure is performed.

  In step ST07, the operator determines whether to change the energy of the charged particle beam 28 (energy change determination procedure). When the adjustment of the electromagnet 7 is not completed with respect to the total energy of the charged particle beam 28 used in the particle beam therapy system 1, the worker determines that the change of the energy is necessary, and proceeds to step ST08. When the adjustment of the electromagnet 7 is completed with respect to the total energy of the charged particle beam 28 used in the particle beam therapy system 1, the operator determines that the change of the energy is not necessary and ends. In step ST08, the operator sets the charged particle beam of the second energy E2 to be emitted from the accelerator 2 (energy change procedure). Thereafter, the process returns to step ST01 to execute a beam position measurement procedure. In steps ST01 to ST04, the beam position of the charged particle beam 28 is determined by the image processing device 27 of the setting parameter generation device 15 based on the position measurement information sig1 measured by the position measurement device 8 arranged in the beam transport system 3. It is a current pattern determination procedure which is calculated and determines the current pattern Ip1 of the electromagnet 7 on the upstream side of the arrangement position of the position measurement device 8 from the beam position.

  The measurement order of the beam position and the electromagnet 7 to be adjusted will be described using FIG. The first measurement point P1 is the position of the port 65a. The electromagnets 7 to be adjusted at the first measurement point P1 are a hexapole electromagnet 64 and a quadrupole electromagnet 63a. The second measurement point P2 is the position of the port 65b. The electromagnets 7 to be adjusted at the second measurement point P2 are a deflection electromagnet 62a, and a six-pole electromagnet 64 and a four-pole electromagnet 63a on the upstream side thereof. At the second measurement point P2, there is almost no readjustment of the already adjusted hexapole electromagnet 64 and quadrupole electromagnet 63a. However, when the adjustment of the deflection electromagnet 62a is difficult, the hexapole electromagnet 64 and the quadrupole electromagnet 63a are readjusted. The readjustment of the already adjusted electromagnet at the downstream measuring point is also performed in the same way.

  The third measurement point P3 is the position of the port 65c. The electromagnets 7 to be adjusted at the third measurement point P3 are the quadrupole electromagnets 63b and 63c, and the hexapole electromagnet 64, the quadrupole electromagnet 63a, and the deflection electromagnet 62a on the upstream side thereof. The fourth measurement point P4 is the position of the port 65d. The electromagnets 7 to be adjusted at the fourth measurement point P4 are the deflection electromagnet 62b, the six-pole electromagnet 64 on the upstream side thereof, the four-pole electromagnets 63a to 63c, and the deflection electromagnet 62a. The fifth measurement point P5 is the position of the port 65e. The electromagnets 7 to be adjusted at the fifth measurement point P5 are the quadrupole electromagnets 63d and 63e, the hexapole electromagnet 64 on the upstream side of these, the quadrupole electromagnets 63a to 63c, and the deflection electromagnets 62a and 62b.

  The flowchart of FIG. 14 will be described. The flowchart of FIG. 14 corresponds to the measurement order of the second example of FIG. 12, and the positions of steps ST07 and ST08 in the flowchart of FIG. 13 are different. Parts different from FIG. 13 will be described. In step ST02, when the beam position is within the design range, the process proceeds to step ST07, and when the beam position is not within the design range, the process proceeds to step ST03. In step ST07, the operator determines whether to change the energy of the charged particle beam 28 (energy change determination procedure). When the adjustment of the electromagnet 7 is not completed with respect to the total energy of the charged particle beam 28 used in the particle beam therapy system 1, the worker determines that the change of the energy is necessary, and proceeds to step ST08. When the adjustment of the electromagnet 7 is completed with respect to the total energy of the charged particle beam 28 used in the particle beam therapy system 1, the operator determines that the change of the energy is not necessary, and proceeds to step ST05.

  In step ST08, the operator sets the charged particle beam of the second energy E2 to be emitted from the accelerator 2 (energy change procedure). Thereafter, the process returns to step ST01 to execute a beam position measurement procedure. When it is determined that the adjustment of the electromagnet 7 is completed with respect to the total energy of the charged particle beam 28 used in the particle beam therapy system 1 in step ST07, and no measurement point P remains in step ST05, That is, when the adjustment work at all measurement points is completed, the work of the flowchart of FIG. 14 is ended.

  The start-up period of the particle beam therapy system in the case of applying the electromagnet adjustment method of the beam transport system according to the first embodiment will be described with reference to FIG. The start-up period of the particle beam therapy system is determined by installation periods Ta1, Ta2 and Ta3 which are periods in which three devices are installed and assembled, and adjustment periods Tb1 and Tb2 which are periods in which beam adjustment of two devices is performed. The installation period Ta1 is a period of installation and assembly of the accelerator 2, the installation period Ta2 is a period of installation and assembly of the beam transport system 3, and the installation period Ta3 is a period of installation and assembly of the irradiation apparatus 4. The adjustment period Tb1 is a period in which the beam adjustment of the accelerator 2 and the beam transport system 3 is performed, and the adjustment period Tb2 is a period in which the beam adjustment of the irradiation device 4 is performed. The start-up period of the conventional particle beam therapy system is the total period of the assembly process 66a and the adjustment process 67a, and is the start-up period T1 shown in FIG. In the start-up of the conventional particle beam therapy system, work of installation periods Ta1, Ta2 and Ta3 is sequentially performed, and then work of adjustment periods Tb1 and Tb2 is sequentially performed.

  The start-up period of the particle beam therapy system when the electromagnet adjustment method of the beam transport system according to the first embodiment is applied is a period when the adjustment step 67b started from the middle of the assembly step 66b and the assembly step 66b is completed, This is the rising period T2 shown in FIG. The electromagnet adjustment method of the beam transport system according to the first embodiment can perform spill feedback based on dosimetry information sig2 measured by the dose monitor 21 inserted in the vacuum duct 29 from the port 65 provided in the beam transport system 3 Therefore, the adjustment period Tb1 for performing the beam adjustment of the accelerator 2 and the beam transport system 3 can be started from the upstream device of which installation and assembly in the beam transport system 3 are completed. For this reason, in the electromagnet adjustment method of the beam transport system according to the first embodiment, it is started from the middle of the installation period Ta2. The start-up period T2 of the particle beam therapy system when applying the electromagnet adjustment method of the beam transport system according to the first embodiment is shorter than the start-up period T1 of the conventional particle beam therapy system. For example, it is assumed that the installation periods Ta1, Ta2, and Ta3 are two months, and the adjustment periods Tb1 and Tb2 are three and two months, respectively. The launch period T1 of the conventional particle beam therapy system is 11 months. On the other hand, the start-up period T2 of the particle beam therapy system when the electromagnet adjustment method of the beam transport system according to the first embodiment is applied is 7 to 8 months, which is 3 to 4 months more than the conventional one. Shortening becomes possible.

  As described above, when spill feedback is applied to the conventional particle beam therapy system, after the installation and assembly of the beam transportation system and the irradiation system are completed, the dose measured by the dose monitor of the irradiation system is It must be used to provide feedback to the RFKO controller. Therefore, the conventional particle beam therapy system can not simultaneously perform the electromagnet adjustment of the beam transport system and the installation and assembly of the equipment of the irradiation system, and the work of setting up the particle beam therapy system takes a long time. On the other hand, the particle beam therapy system 1 when the electromagnet adjustment method of the beam transport system according to the first embodiment is applied is a dose monitor 21 inserted into the vacuum duct 29 from the port 65 provided in the beam transport system 3. Since spill feedback can be performed based on the dosimetry information sig2 measured by the above, charged particle beam is obtained in the middle of the beam transport system 3 while obtaining the charged particle beam 28 of constant intensity (constant dose) to which spill feedback is applied. It becomes possible to observe 28 and adjust the apparatus which controls a beam position etc. In addition, since the charged particle beam 28 does not have to be introduced into the irradiation chamber 13, it is possible to carry out work in the irradiation room simultaneously with the accelerator adjustment work. Therefore, the particle beam therapy system 1 in the case of applying the electromagnet adjustment method of the beam transport system according to the first embodiment can perform the electromagnet adjustment of the beam transport system 3 even if the assembly of the irradiation device 4 is not completed. The start-up operation of the particle beam therapy system can be made in a shorter time than before.

  As described above, the electromagnet adjustment method of the beam transport system according to the first embodiment includes the beam transport system for adjusting the electromagnet 7 of the beam transport system 3 that transports the charged particle beam 28 emitted from the accelerator 2 to the irradiation device 4. In the electromagnet adjustment method, the radiation dose value (dose measurement value Dm) of the charged particle beam 28 is calculated based on the dose measurement information sig2 measured by the dose measurement device 9 disposed in the beam transport system 3, and charging is performed. Constant dose control procedure for controlling the accelerator by the dose control device (RFKO controller 5) so that the dose value (dose measurement value Dm) of the particle beam 28 falls within the dose allowable range including the target value (dose target value Di) And charging based on position measurement information sig1 measured by the position measurement device 8 disposed in the beam transport system 3 using the charged particle beam 28 controlled in the fixed dose control procedure. Is calculated beam position of a child beam 28, characterized in that it comprises a current pattern determination procedure for determining based on the current pattern Ip1 upstream of the electromagnet 7 in beam position than the arrangement position of the position measuring instrument 8. The current pattern determination procedure is characterized in that the current pattern Ip1 of the electromagnet 7 is changed so that the beam position of the charged particle beam 28 falls within the design range when the beam position of the charged particle beam 28 exceeds the design range. Do. Due to this feature, the electromagnet adjustment method of the beam transport system of the first embodiment is based on the radiation dose value of the charged particle beam 28 based on the dosimetry information sig2 measured by the dosimetry device 9 disposed in the beam transport system 3. Since the electromagnet 7 of the beam transport system 3 is adjusted after (dose measurement value Dm) comes within the dose tolerance range including the target value (dose target value Di), assembly of the apparatus of the irradiation apparatus 4 is completed. The electromagnet adjustment of the beam transport system 3 can be performed without it, and the start-up operation of the particle beam therapy system can be made in a shorter time than before.

Second Embodiment
FIG. 16 is a diagram showing the configuration of the electromagnet adjustment device according to the second embodiment of the present invention. The electromagnet adjustment device 10 according to the second embodiment is an example in which the dosimetry device 9 for generating dosimetry information sig2 of the charged particle beam 28 is disposed upstream of the electromagnet 7 to be measured. The dosimetry information sig2 is measured in order to perform spill feedback and emit a charged particle beam 28 of constant intensity (constant dose) from the accelerator 2, so the charged particle beam 28 can be from anywhere downstream of the accelerator 2. The dosimetry information sig2 may be generated by measuring the dose of For example, if the dose monitor 21 of the dose measuring instrument 9 is disposed on the side closest to the accelerator 2 of the beam transport system 3, there is no need to change the position of the dose monitor 21 when changing the measurement point of the beam position, The measurement of the next beam position can be started in a shorter period than that of the electromagnet adjustment device 10 of the first embodiment.

  Also in the case of using the electromagnet adjustment device 10 of the second embodiment, the method shown in the flowchart of FIG. 13 and the flowchart of FIG. 14 can be applied to the electromagnet adjustment method of the beam transport system. Therefore, the electromagnet adjustment method of the beam transport system of the second embodiment is the same as the electromagnet adjustment method of the beam transport system of the first embodiment, even if the assembly of the apparatus of the irradiation device 4 is not completed. Can be adjusted, and the work of launching particle beam therapy system can be made in a shorter time than before.

Third Embodiment
FIG. 17 is a diagram showing the configuration of the electromagnet adjustment device according to the third embodiment of the present invention. 18 shows the configuration of the dose signal processing apparatus of FIG. 17, FIG. 19 shows the monitor current of the position monitor of FIG. 17, and FIG. 20 shows the configuration of the position signal processing apparatus of FIG. It is. In the electromagnet adjustment device 10 according to the third embodiment, the position measurement device 8 includes the position monitor 72 and the high voltage generator 73, and the dose measurement device 9 is an example of the Faraday cup 71. The Faraday cup 71 is a metal that collects charges generated by the impact of charged particles, and is a detector that generates a current according to the number of charged particles that have entered. Since the Faraday cup 71 blocks the charged particle beam 28, it also has the function of the beam damper 23. Along with the change of the device configuration of the position measurement device 8 and the dose measurement device 9, the setting parameter generation device 15 is changed to a configuration including the dose signal processing device 74, the position signal processing device 75, and the current pattern setting device 31. ing.

  Although the dose signal processing device 74 is basically the same as the dose signal processing device 25 of the first embodiment, as shown in FIG. 18, the dose measurement information sig2 which is an input minute analog signal is converted to the voltage V1. The current-voltage converter 51 to be converted is changed to a current-voltage converter 76. Since the current output from the dose monitor 21 and the current output from the faraday cup 71 are different even if the current dose converter 76 has the same dose, that is, the characteristics of the current and the dose are different, It has been corrected to be

  The position monitor 72 is provided with a plurality of wires for the x direction and the y direction as shown in FIG. 19, and the current of the ions obtained by ionizing the enclosed gas such as argon or nitrogen by passing the charged particle beam 28. Is detected by a plurality of wires to which the high voltage generated by the high voltage generator 73 is applied. The position monitor 72 is a transmissive position monitor through which the charged particle beam 28 passes. The minute current detected by the position monitor 72 is position measurement information sig1. That is, the position measurement information sig1 is current information. The position measurement information sig1 detected by the position monitor 72 is output to the position signal processing device 75. In FIG. 19, five wires are shown respectively for the x direction and the y direction. Wires for the x direction are labeled wx1, wx2, wx3, wx4, wx5, and wires for the y direction are labeled wy1, wy2, wy3, wy4, wy5. Monitor currents Ix1, Ix2, Ix3, Ix4, Ix5 are detected from the wires wx1, wx2, wx4, wx5 respectively, and monitor currents Iy1, Iy2, Iy3, Iy4 from the wires wy1, wy2, wy3, wy4, wy5 respectively , Iy5 are detected. The monitor currents Ix1, Ix2, Ix3, Ix4, Ix5 are position measurement information sig1x in the x direction, and the monitor currents Iy1, Iy2, Iy3, Iy4, Iy5 are position measurement information sig1y in the y direction. The position measurement information sig1 includes position measurement information sig1x in the x direction and position measurement information sig1y in the y direction.

  For example, as shown in FIG. 20, the position signal processing device 75 performs signal conversions 91a and 91b for converting the monitor currents of the position measurement information sig1x and sig1y, a numerical operation unit 80, an output unit 81, a computer 82, and a display device. 83, a storage unit 84 is provided. The signal conversion unit 91a that performs signal conversion of the position measurement information sig1x includes a current-voltage conversion unit 77, an amplifier unit 78, and an AD conversion unit 79. The signal conversion unit 91b that performs signal conversion of the position measurement information sig1y includes a current-voltage conversion unit 77, an amplifier unit 78, and an AD conversion unit 79. The current-voltage conversion unit 77 of the signal conversion unit 91a includes a plurality of current-voltage converters corresponding to the number of monitor currents, and the monitor currents Ix1 and Ix2 of the position measurement information sig1x which are input minute analog signals. Each of Ix3, Ix4, and Ix5 is converted to a voltage V1x. The amplifier unit 78 includes a plurality of amplifiers corresponding to the number of monitor currents, and each amplifier amplifies the voltage V1x to a voltage V2x. The AD conversion unit 79 includes a plurality of AD converters corresponding to the number of monitor currents, and each AD converter performs analog-digital conversion (AD conversion) on the voltage V2x to generate a digital signal dt1x. The voltage V1x, the voltage V2x, and the digital signal dt1x are generated by the number corresponding to the number of monitor currents.

  The current-voltage conversion unit 77 of the signal conversion unit 91 b is the same as the current-voltage conversion unit 77 of the signal conversion unit 91 a. The current-voltage conversion unit 77 of the signal conversion unit 91b includes a plurality of current-voltage converters corresponding to the number of monitor currents, and monitor currents Iy1 and Iy2 of the position measurement information sig1y which are input minute analog signals, Each of Iy3, Iy4 and Iy5 is converted to a voltage V1y. The amplifier unit 78 includes a plurality of amplifiers corresponding to the number of monitor currents, and each amplifier amplifies the voltage V1y to a voltage V2y. The AD conversion unit 79 includes a plurality of AD converters corresponding to the number of monitor currents, and each AD converter performs analog-digital conversion (AD conversion) on the voltage V2y to generate a digital signal dt1y. The voltage V1y, the voltage V2y, and the digital signal dt1y are generated by the number corresponding to the number of monitor currents.

  The numerical operation unit 80 calculates the position information digital signal dtp1x in the x direction of the charged particle beam 28 from the plurality of digital signals dt1x, and calculates the position information digital signal dtp1y in the y direction of the charged particle beam 28 from the plurality of digital signals dt1y Do. The position information digital signal dtp1x is a beam position (coordinates of center) of the charged particle beam 28 in the x direction, a beam size (spread) in the x direction, and a beam distribution in the x direction. The position information digital signal dtp1y is a beam position (coordinates of center) of the charged particle beam 28 in the y direction, a beam size (spread) in the y direction, and a beam distribution in the y direction. The beam size (spread) is a length corresponding to 1σ of a one-dimensional Gaussian distribution. The beam distribution is a distribution of current values or voltage values corresponding to the position of each wire.

  The output unit 81 matches the transmission format of the position information digital signals dtp1x and dtp1y with the transmission format to the computer 82, that is, converts the transmission format, and generates transmission signals fdtp1x and fdtp1y. The computer 82 restores the beam position (coordinates of the center), beam size (spread), and beam distribution in the x and y directions from the transmission signals fdtp1x and fdtp1y. The beam position, beam size, and beam distribution 61 in the x and y directions output from the computer 82 are displayed on the display unit 83 and stored in the storage unit 84. The display device 83 is a display or the like, and the storage device 84 is a memory, a hard disk (HDD) or the like. The calculator 82 also outputs position information sig4 to the current pattern setting device 31. Position information sig4 is beam position (coordinate of center) in x direction and y direction in charged particle beam 28, beam size (spread) in x direction and y direction, and beam distribution in x direction and y direction.

  Also in the case of using the electromagnet adjustment device 10 of the third embodiment, the method shown in the flowchart of FIG. 13 and the flowchart of FIG. 14 can be applied to the electromagnet adjustment method of the beam transport system. Therefore, the electromagnet adjustment method of the beam transport system of the third embodiment is the same as the electromagnet adjustment method of the beam transport system of the first embodiment, even if the assembly of the apparatus of the irradiation device 4 is not completed. Can be adjusted, and the work of launching particle beam therapy system can be made in a shorter time than before.

  Further, the electromagnet adjustment device 10 according to the third embodiment needs to dispose the beam damper 23 as in the electromagnet adjustment method of the beam transport system according to the first and second embodiments by using the faraday cup 71 as the dose measurement device 9. There is no In the beam transport system 3 which is started up using the electromagnet adjustment device 10 of the third embodiment, the installation work of the device at each measurement point P is reduced, and the size of the port 65 can be reduced. When the port for the beam damper 23 is provided, the port for the beam damper 23 can be eliminated. The beam transport system 3 which is started up using the electromagnet adjustment device 10 of the third embodiment can reduce the size of the port 65 or eliminate the port for the beam damper 23, so shortening and heightening the vacuum duct 29 of the beam transport system 3 It is possible to evacuate.

Fourth Embodiment
FIG. 21 is a diagram showing the configuration of the electromagnet adjustment device according to the fourth embodiment of the present invention. In the electromagnet adjustment device 10 according to the fourth embodiment, the position measurement device 8 includes the screen monitor 22 and the camera 24, and the dose measurement device 9 is an example of the Faraday cup 71. In the electromagnet adjustment device 10 of the fourth embodiment, the dose monitor 21 and the high voltage generator 26 of the electromagnet adjustment device 10 of the first embodiment are changed to a faraday cup 71, and the dose signal of the electromagnet adjustment device 10 of the first embodiment The processing unit 25 is changed to the dose signal processing unit 74 described in the third embodiment. Since the Faraday cup 71 also has the function of a beam damper, the screen monitor 22 is disposed upstream of the Faraday cup 71. The Faraday cup 71 measures the dose of the charged particle beam 28 transmitted through the screen monitor 22. The thickness and the material of the screen monitor 22, that is, the thickness and the material of the fluorescent plate are selected in accordance with the detection sensitivity of the Faraday cup 71.

  Also in the case of using the electromagnet adjustment device 10 of the fourth embodiment, the method shown in the flowchart of FIG. 13 and the flowchart of FIG. 14 can be applied to the electromagnet adjustment method of the beam transport system. Therefore, the electromagnet adjustment method of the beam transport system of the fourth embodiment is the same as the electromagnet adjustment method of the beam transport system of the first embodiment, even if the assembly of the apparatus of the irradiation device 4 is not completed. Can be adjusted, and the work of launching particle beam therapy system can be made in a shorter time than before. Further, since the electromagnet adjustment device 10 of the fourth embodiment does not need to dispose the beam damper 23, the beam transport system 3 is started up using the electromagnet adjustment device 10 of the fourth embodiment as in the third embodiment. The installation work of the device at each measurement point P is reduced, and the size of the port 65 can be reduced. When the port for the beam damper 23 is provided, the port for the beam damper 23 can be eliminated. The beam transport system 3 which is started up using the electromagnet adjustment device 10 of the fourth embodiment can reduce the size of the port 65 or eliminate the port for the beam damper 23, so shortening and heightening the vacuum duct 29 of the beam transport system 3. It is possible to evacuate.

Embodiment 5
FIG. 22 is a schematic block diagram of a particle beam therapy system to which the electromagnet adjustment method for beam transport system according to the fifth embodiment of the present invention is applied. FIG. 23 is a diagram showing the configuration of the position measurement device and the setting parameter generation device in the electromagnet adjustment device of FIG. 22, and FIG. 24 is a diagram showing the configuration of the RFKO control device of FIG. The electromagnet adjustment device 10 according to the fifth embodiment is the same as the electromagnet adjustment device 10 according to the first embodiment than the DCCT (DC Current Transformer) measuring device 85 in which the dose measuring device 9 measures the beam residual amount (residual dose) of the accelerator 2. The residual dose measurement information sig5, which is DCCT measurement information measured by the dose measurement device 9, is input to the RFKO control device 5, and the setting parameter generation device 15 sets the image processing device 27 and the current pattern. The difference is that the device 31 is changed. Parts different from the first embodiment will be described.

  The DCCT measuring device 85 measures the direct current of the charged particle beam 28 in the accelerator 2, that is, the current residual amount of beam (DCCT current). The electromagnet adjustment device 10 of the fifth embodiment outputs, to the RFKO controller 5, residual dose measurement information sig5 which is information of the current remaining amount of beam (DCCT current) in the accelerator 2. The RFKO controller 5 generates a control signal siga based on the estimated value of the beam decrease amount (decreased dose) calculated from the value of the beam residual amount (residual dose) as an output dose value, It controls so that the charged particle beam 28 of fixed intensity (fixed dose) is emitted from the accelerator 2. More specifically, the RFKO controller 5 controls the charged particle beam to have a constant intensity (constant dose) such that the estimated outgoing dose value estimated from the value of the beam residual amount (residual dose) falls within the dose allowable range including the target value. Control is performed such that 28 is emitted from the accelerator 2. As shown in FIG. 24, the RFKO control device 5 of the fifth embodiment is different from the RFKO control device 5 of the first embodiment in the circuit configuration for outputting to the PI control circuit 49 from the input unit 44 of the feedback control unit 46. . The PI control circuit 49 receives a dose estimated value Ds which is an estimated output dose value generated by the dose estimated value generation circuit 90. The dose estimated value generation circuit 90 includes an input unit 44, a delay circuit 87, a difference calculator 88, and a correction circuit 89.

  An AD converter 86 generates DCCT current of an analog signal measured by the DCCT measuring instrument 85, and residual dose measurement information sig5 of a digital signal. The input unit 44 of the feedback control unit 46 of the RFKO controller 5 generates a DCCT measurement value Dd based on the residual dose measurement information sig5. The delay circuit 87 generates a delayed DCCT measurement value Ddd in which a predetermined delay time td is delayed. The delayed DCCT measurement value Ddd corresponds to a DCCT measurement value that is earlier by the delay time td than the current DCCT measurement value Dd. The difference calculator 88 calculates a decreased dose value Ds0 obtained by subtracting the DCCT measurement value Dd from the delay DCCT measurement value Ddd. The correction circuit 89 corrects the reduced dose value Ds0 to be in the same range as the dose target value Di to generate a dose estimate value Ds. The dose estimated value Ds is input to the PI control circuit 49, and the PI control circuit 49 executes PI control (proportional integral control) based on the dose estimated value Ds and the dose target value Di to generate a modulation control signal sigc. When executing PI control, the PI control circuit 49 calculates a dose difference which is a difference between the dose target value Di and the dose estimate value Ds, and based on the dose difference, the dose target value Di, and the dose estimate value Ds. A modulation control signal sigc is generated.

  In the electromagnet adjustment device 10 according to the fifth embodiment, since the dose value to be compared with the dose target value Di is not directly measured in the beam transport system 3, that is, an operation delay including a delay time td occurs in the calculated dose estimated value Ds. Therefore, the dose estimated value Ds calculated by the dose estimated value generation circuit 90 is reset as necessary. When the dose target value Di is changed during beam emission, the DCCT measurement value Dd which is the output of the input unit 44 and the delay DCCT measurement value Ddd which is the output of the delay circuit are reset, and then the residual dose measurement information sig5 is obtained. Data acquisition, that is, updating of the DCCT measurement value Dd of the input unit 44 is performed.

  Also in the case of using the electromagnet adjustment device 10 of the fifth embodiment, the method shown in the flowchart of FIG. 13 and the flowchart of FIG. 14 can be applied to the electromagnet adjustment method of the beam transport system. Therefore, the electromagnet adjustment method of the beam transport system of the fifth embodiment is the same as the electromagnet adjustment method of the beam transport system of the first embodiment, even if the assembly of the apparatus of the irradiation device 4 is not completed. Can be adjusted, and the work of launching particle beam therapy system can be made in a shorter time than before. Unlike the electromagnet adjustment device 10 according to the first embodiment, the electromagnet adjustment device 10 according to the fifth embodiment does not need to change the position of the dosimetry device 9 when changing the measurement point of the beam position. The measurement of the next beam position can be started in a period shorter than that of the electromagnet adjustment device 10 of 1.

  As described above, the electromagnet adjustment method of the beam transport system according to the fifth embodiment includes the beam transport system for adjusting the electromagnet 7 of the beam transport system 3 for transporting the charged particle beam 28 emitted from the accelerator 2 to the irradiation device 4. A charged particle emitted from the accelerator 2 on the basis of residual dose measurement information sig5 which is information on the residual dose of the charged particle beam 28 measured by the dose measurement device 9 disposed in the accelerator 2, which is an electromagnet adjustment method. The dose control device is configured so that the radiation dose value of the beam 28 is estimated, and the estimated radiation dose value (dose estimation value Ds) of the estimated charged particle beam 28 falls within the dose tolerance range including the target value (dose dose value Di). A fixed dose control procedure for controlling the accelerator 2 by (RF KO controller 5) and a charged particle beam 28 controlled by the fixed dose control procedure, The beam position of the charged particle beam 28 is calculated based on the position measurement information sig1 measured by the measuring device 8, and the current pattern Ip1 of the electromagnet 7 on the upstream side of the arrangement position of the position measuring device 8 is based on the beam position. And C. determining a current pattern determination procedure. The current pattern determination procedure is characterized in that the current pattern Ip1 of the electromagnet 7 is changed so that the beam position of the charged particle beam 28 falls within the design range when the beam position of the charged particle beam 28 exceeds the design range. Do. The electromagnet adjustment method of the beam transport system according to the fifth embodiment estimates the charged particle beam 28 estimated based on the residual dose measurement information sig5 measured by the dose measurement device 9 disposed in the accelerator 2 according to this feature. Since the electromagnet 7 of the beam transport system 3 is adjusted after the output dose value (dose estimate value Ds) comes within the dose tolerance range including the target value (dose target value Di), the assembly of the equipment of the irradiation apparatus 4 Even if it is not completed, the electromagnet adjustment of the beam transport system 3 can be performed, and the start-up work of the particle beam therapy system can be made in a shorter time than in the past.

  The current pattern setting device 31 of the first to fifth embodiments includes a computer. The computer of the current pattern setting device 31 and the computers 57 and 82 are provided with a processor 98 and a memory 99 as shown in FIG. The computer implemented by the current pattern setting device 31 and the functions implemented by the computers 57 and 82 are implemented by the processor 98 and the memory 99. FIG. 25 is a diagram showing a hardware configuration for realizing the function of a computer. The computer of the current pattern setting device 31 and the functions of the computers 57 and 82 are realized by the processor 98 executing a program stored in the memory 99. Further, the functions of the computers 57 and 82 may be such that a plurality of processors 98 and a plurality of memories 99 cooperate to execute the functions. Moreover, in the present invention, it is possible to combine each embodiment or to appropriately modify or omit each embodiment within the scope of the invention.

  DESCRIPTION OF SYMBOLS 2 ... accelerator, 3 ... beam transport system, 4 ... irradiation apparatus, 5 ... RFKO control apparatus (emission amount control apparatus), 6 ... amplifier, 7 ... electromagnet, 8 ... position measurement apparatus, 9 ... dosimetry apparatus, 19 ... RFKO Electrode (adjusting electrode) 21, 21a: dose monitor 22, 22, 22a: screen monitor, 24: camera, 28: charged particle beam, 37: AM modulator (control signal generator), 60: camera image (image information) 62a, 62b: deflection electromagnet, 63a, 63b, 63c, 63d, 63e: quadrupole electromagnet, 64: hexapole electromagnet, 71: faraday cup, 72: position monitor, sig1, sig1x, sig1y, position measurement information, sig2: dose Measurement information, sig3 ... dose value information, sig5 ... residual dose measurement information, siga ... control signal, Dm ... dose measurement value, Ds ... dose estimated value, Di ... dose eye Value, Ip1 ... current pattern, P, P1, P2, P3, P4, P5 ... measurement point, E1, E2, E3, E4 ... energy, Ix1, Ix2, Ix3, Ix4, Ix5 ... monitor current, Iy1, Iy2, Iy3 , Iy4, Iy5 ... Monitor current

Claims (12)

An electromagnet adjustment method of a beam transport system for adjusting an electromagnet of a beam transport system for transporting a charged particle beam emitted from an accelerator to an irradiation apparatus,
A dose value of the charged particle beam is calculated based on dosimetry information measured by a dose measuring device arranged in the beam transport system, and the dose tolerance of the charged particle beam includes a target value. A constant dose control procedure for controlling the accelerator by the dose control device to be within the range;
Using the charged particle beam controlled by the fixed dose control procedure, the beam position of the charged particle beam is calculated based on position measurement information measured by a position measurement device arranged in the beam transport system. A current pattern determination procedure of determining a current pattern of the electromagnet upstream of an arrangement position of the position measurement device based on the beam position;
The current pattern determination procedure
Changing the current pattern of the electromagnet so that the beam position of the charged particle beam falls within the design range when the beam position of the charged particle beam exceeds the design range How to adjust the electromagnet of the system. The emission amount control device receives dose value information obtained by digitizing the dose measurement information, and generates a dose measurement value generated based on the dose value information and the target value of the dose of the charged particle beam. A control signal generator that generates a control signal based on the dose difference;
The electromagnet adjustment of a beam transport system according to claim 1, wherein the accelerator includes an adjusting electrode for adjusting the emission dose value of the charged particle beam based on a signal obtained by amplifying the control signal by an amplifier. Method. The position measuring device comprises a screen monitor and a camera.
The method according to claim 1, wherein the position measurement information is image information including light emission of the charged particle beam captured by the camera. The position measuring device is a position monitor through which the charged particle beam is transmitted,
The method of claim 1 or 2, wherein the position measurement information is current information measured by the position monitor. The dosimetry device is a dose monitor through which the charged particle beam passes;
The electromagnet adjustment method of a beam transport system according to any one of claims 1 to 4, wherein the dose measurement information is current information measured by the dose monitor. 6. The method of claim 5, wherein the dose monitor is disposed upstream of the electromagnet. The position measuring device is a position monitor through which the charged particle beam is transmitted,
The position measurement information is current information measured by the position monitor,
The dosimetry device is a faraday cup disposed downstream of the position monitor,
The method of claim 1 or 2, wherein the dosimetry information is current information measured by the Faraday cup. The position measuring device comprises a screen monitor and a camera.
The position measurement information is image information including light emission of the charged particle beam captured by the camera,
The dosimetry device is a faraday cup disposed downstream of the screen monitor,
The method of claim 1 or 2, wherein the dosimetry information is current information measured by the Faraday cup. An electromagnet adjustment method of a beam transport system for adjusting an electromagnet of a beam transport system for transporting a charged particle beam emitted from an accelerator to an irradiation apparatus,
Based on residual dose measurement information, which is information on the residual dose of the charged particle beam measured by a dose measuring device arranged in the accelerator, an emitted dose value of the charged particle beam emitted from the accelerator is estimated. A constant dose control procedure for controlling the accelerator by an emission control device such that the estimated emission dose value of the charged particle beam estimated falls within a dose allowable range including a target value;
Using the charged particle beam controlled by the fixed dose control procedure, the beam position of the charged particle beam is calculated based on position measurement information measured by a position measurement device arranged in the beam transport system. A current pattern determination procedure of determining a current pattern of the electromagnet upstream of an arrangement position of the position measurement device based on the beam position;
The current pattern determination procedure
Changing the current pattern of the electromagnet so that the beam position of the charged particle beam falls within the design range when the beam position of the charged particle beam exceeds the design range How to adjust the electromagnet of the system. The emission amount control device generates a control signal based on a dose difference between the estimated emission dose value estimated based on the received residual dose measurement information and the target value of the dose of the charged particle beam. Equipped with a signal generator,
10. The electromagnet adjustment of a beam transport system according to claim 9, wherein the accelerator includes an adjusting electrode for adjusting the emission dose value of the charged particle beam based on a signal obtained by amplifying the control signal by an amplifier. Method. Where the current patterns of the plurality of electromagnets are determined for the plurality of energies of the charged particle beam,
The current pattern determination procedure for all the electromagnets to be adjusted for the first energy is performed,
After that, changing the next energy, the current pattern determination procedure targeting all the electromagnets to be adjusted with respect to the changed energy is performed until all the energy is finished. The electromagnet adjustment method of the beam transport system according to any one of claims 1 to 10. Where the current patterns of the plurality of electromagnets are determined for the plurality of energies of the charged particle beam,
The current pattern determination procedure
Based on the beam position calculated based on the position measurement information at which the beam position is measured at the first measurement point for each energy of the charged particle beam, on the upstream side of the arrangement position of the position measurement device A first determination procedure is performed to determine the current pattern of the electromagnet,
After that, based on the beam position calculated based on the position measurement information, the beam position is measured for each energy of the charged particle beam at a measurement point downstream of the previous measurement point. 11. A method according to any one of the preceding claims, characterized in that a second determination procedure for determining the current pattern of the electromagnet upstream of the position of the position measuring device is carried out until the end of the last measurement point. The electromagnet adjustment method of the beam transport system as described in a term.

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