Particle beam irradiation system and particle beam irradiation facility

Abstract

The present invention reduces the setting area of a particle beam therapy system. A particle beam irradiation system according to an aspect of the present disclosure includes an accelerator disposed on the ground and configured to accelerate a charged particle beam; a transport device configured to transport the charged particle beam emitted from the accelerator; an irradiation device configured to irradiate an irradiation target with the charged particle beam transported by the transport device; and a gantry disposed on the ground and configured to mount the irradiation device. In addition, the gantry includes a rotating body configured to rotate the irradiation device around the irradiation target, and a support device configured to support the rotating body from the ground at a position at which a projection of the rotating body on the ground and a projection of at least one of the accelerator or the transport device on the ground at least partially overlap.

Description

TECHNICAL FIELD

[0001] The present application relates to a particle beam irradiation system and a particle beam irradiation facility. BACKGROUND

[0002] Radiation therapy is a therapy method of irradiating a patient part with a radiation ray such as an X-ray or a particle beam. The most popular device among devices for radiation therapy is an X-ray therapy device. However, since the radiation dose of the X-ray is largest on the surface of the body, and attenuates while passing through the inside of the body, there is a concern that normal tissues located before and after the tumor are affected. On the other hand, the particle beam has a higher radiation dose distribution in a portion called a Bragg curve which is deep in the range. In particle beam therapy, the Bragg peak is adjusted to the position of the patient part, and irradiation is performed with improved radiation dose concentration, taking advantage of the feature that the portion deep in the Bragg peak is not given a radiation dose. Compared with X-ray therapy, particle beam therapy can improve the radiation dose concentration to the patient part, and suppress the influence on the periphery of the patient part. A particle beam therapy system that realizes such therapy is sought for further popularization.

[0003] However, the particle beam therapy system is higher in price than the X-ray therapy device, and is large in installation area, which hinders popularization. On the basis of further popularization of the particle beam therapy system, reduction in the installation area, miniaturization, and lower price of the particle beam therapy system are sought.

[0004] A miniaturized particle beam therapy system is disclosed in Patent Literature 1. The particle beam therapy system includes a synchrotron that accelerates a charged particle beam, a high-energy beam transport system that transports the charged particle beam accelerated by the synchrotron, and a rotating gantry that has an irradiation field forming device that irradiates the charged particle beam transported by the high-energy beam transport system to a patient. In the technology disclosed in Patent Literature 1, the high-energy beam transport system that transports the charged particle beam between the synchrotron and the rotating gantry is configured so that the center of the orbit of the charged particle beam from the synchrotron and the center of rotation of the rotating gantry are substantially in the same straight line, and reduction in the installation area of the particle beam therapy system is achieved.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Publication No. 2018-187308 SUMMARY

[0008] PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] An object of the present disclosure is to provide a technology that reduces the installation area of a particle beam therapy system.

[0010] Means for solving the problem

[0011] The particle beam irradiation system according to one aspect of the present disclosure includes an accelerator disposed on the ground and accelerating a charged particle beam; a transport device transporting the charged particle beam emitted from the accelerator; an irradiation device irradiating the charged particle beam transported by the transport device toward an irradiation target; and a gantry disposed on the ground and mounting the irradiation device. In addition, the gantry includes a rotating body rotating the irradiation device around the irradiation target and a support device supporting the rotating body from the ground at a position where a projection of the rotating body on the ground and a projection of at least one of the accelerator or the transport device on the ground overlap.

[0012] Effects of the invention

[0013] According to one aspect of the present disclosure, a particle beam irradiation system having a reduced installation area can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a bird's-eye view of a particle beam therapy system.

[0015] Figure 2 is a plan view of a particle beam therapy system.

[0016] Figure 3 is a side view of a particle beam therapy system.

[0017] Figure 4 is a front view of a particle beam therapy system.

[0018] Figure 5 is a view of a particle beam therapy system showing a state of rotation of a rotating body.

[0019] Figure 6 is a view showing a state in which a particle beam therapy system is disposed in a house. DETAILED DESCRIPTION

[0020] Embodiments of the present invention will be described with reference to the accompanying drawings.

[0021] Here, as an example of a particle beam irradiation system irradiating a particle beam toward an irradiation target, a particle beam therapy system irradiating a particle beam toward a cancer tissue of a cancer patient will be described.

[0022] Figure 1 is a bird's-eye view of a particle beam therapy system. Figure 2 is a plan view of a particle beam therapy system, Figure 3 is a side view of a particle beam therapy system, Figure 4 is a front view of a particle beam therapy system. Figure 2 is a plan view of a particle beam therapy system. Figure 1 is a view of the particle beam irradiation system shown inFigure 3 The side view is Figure 1 The diagram shows the particle beam irradiation system as observed from the direction of arrow B. Figure 4 The main view is Figure 1 The diagram shows the particle beam irradiation system as observed from the direction of arrow C.

[0023] First, a brief overview of the structure and operation of the particle beam irradiation system will be provided.

[0024] The particle beam therapy system includes a linear accelerator 2, a low-energy beam delivery device 3, a synchrotron 4, a high-energy beam delivery device 5, a rotating gantry 1, and an irradiation nozzle 6.

[0025] Linear accelerator 2 accelerates charged particles, generating a charged particle beam. This beam is then transported by low-energy beam delivery device 3 and injected into synchrotron 4. The charged particle beam injected into synchrotron 4 is accelerated to the desired energy and ejected into high-energy beam delivery device 5. The charged particle beam ejected from synchrotron 4 passes through high-energy beam delivery device 5 and is transported to rotating gantry 1.

[0026] The rotating frame 1 has: a rotating body 11 that rotates about a rotation axis 30; a frame conveyor line 19 that is rotatably connected to the high-energy beam delivery device 5 relative to the high-energy beam delivery device 5 and rotates together with the rotating body 11; and a support device 14 that rotatably supports the rotating body 11.

[0027] Reference Figure 4 Inside the treatment chamber 8, an irradiation nozzle 6 is provided on the rotating frame 1, rotating together with the rotating body 11. The irradiation nozzle 6 has its front end facing the rotation axis 30 and rotates about the rotation axis 30. The treatment table 7 for placing the patient is configured to place the patient in the direction in which the front end of the irradiation nozzle 6 is facing.

[0028] A charged particle beam from the high-energy beam delivery device 5 is delivered to the irradiation nozzle 6 via the frame conveyor line 19, and irradiates the affected area of ​​the patient placed on the treatment table 7 from the front end of the irradiation nozzle 6. By rotating the rotating body 11, the irradiation nozzle 6 rotates around the treatment table 7, allowing the direction from which the charged particle beam is irradiated onto the patient's affected area to vary. In this embodiment, the treatment table 7 is described as an example of a treatment table having a top plate for placing the patient, three parallel drive mechanisms for driving the top plate in the XYZ axis direction, and a rotary drive mechanism for rotating the top plate around the Z axis, but it is not limited to this. For example, it could be another treatment table, such as a robotic arm type treatment table having a drive mechanism in the Z-axis direction, a first arm and a first arm rotation mechanism, a second arm and a second arm rotation mechanism, a top plate, and a rotary mechanism for rotating the top plate in pitch / roll / yaw directions.

[0029] Next, the structure and operation of each device included in the particle beam therapy system will be described.

[0030] The linear accelerator 2 is provided with an ion source and a linear accelerator. The ion source generates charged particles by colliding high-speed electrons with a neutral gas or the like. The linear accelerator accelerates the charged particles generated in the ion source to a charged particle beam in a state in which the charged particles can be accelerated by the synchrotron 4, and emits the charged particle beam to the low-energy beam transport device 3. The charged particle beam refers to a beam in which charged particles flow thinly. Here, as the charged particles, for example, hydrogen, helium, carbon, nitrogen, oxygen, neon, silicon, argon, or the like is used.

[0031] The low-energy beam transport device 3 is a device that transports the charged particle beam emitted from the linear accelerator 2 using a space in which high vacuum is maintained inside, and transports the charged particle beam to the synchrotron 4.

[0032] The synchrotron 4 is a device that accelerates the charged particle beam from the low-energy beam transport device 3 to an energy (70 MeV to 220 MeV or so) suitable for cancer treatment through a ring-shaped path. The ring-shaped path of the synchrotron 4 is configured by connecting the following components to each other: a bending electromagnet 15A that bends the charged particle beam to a predetermined angle; a quadrupole electromagnet 16A that controls convergence and / or divergence of the charged particle beam in a horizontal direction and a vertical direction; a vacuum duct 17A that is a path of the charged particle beam; and a high-frequency acceleration cavity 21 that accelerates the charged particle beam. In the present embodiment, four bending electromagnets 15A that bend the charged particle beam by 90 degrees are arranged at four corners, and the vacuum duct 17A penetrates through the bending electromagnets 15A, thereby configuring the ring-shaped path.

[0033] In the present embodiment, as a method of installing the synchrotron 4 to the building 100, a method of fixing the bending electromagnet 15A, the quadrupole electromagnet 16A, and the high-frequency acceleration cavity 21 on a stand 22 provided on a floor of the building 100 is adopted.

[0034] In addition, in the present embodiment, the synchrotron 4 is installed to the floor via the stand 22, but the synchrotron 4 can be directly installed to the floor without using the stand 22.

[0035] Further, in the present embodiment, the structure in which four bending electromagnets 15A are arranged in the ring-shaped path is shown, but the structure of the synchrotron 4 is not limited to this. The number of the bending electromagnets 15A of the synchrotron 4 can be less than four, or more than five. Further, in the present embodiment, the bending angle of the bending electromagnets 15A is set to 90 degrees, but the structure of the synchrotron 4 is not limited to this. The bending angle of the bending electromagnets 15A can also be other angles. Further, the synchrotron 4 can also have devices other than the bending electromagnets 15A, the quadrupole electromagnets 16A, and the high-frequency accelerating cavity 21 on the ring-shaped path, the connection portion of the ring-shaped path and the low-energy beam transport device 3, or the connection portion of the ring-shaped path and the high-energy beam transport device 5.

[0036] Further, in the present embodiment, an example in which the linear accelerator 2 and the synchrotron 4 are used as accelerators to accelerate the charged particle beam is shown, but the structure is not limited to this. As other examples, other accelerators such as a cyclotron, a synchrocyclotron, a circular accelerator that makes the orbit of the charged particle beam eccentric to accelerate the charged particle beam, and emits the charged particle beam at an arbitrary energy, and the like can also be used.

[0037] The charged particle beam accelerated by the synchrotron 4 is transported to the high-energy beam transport device 5.

[0038] The high-energy beam transport device 5 is a device that transports the charged particle beam accelerated by the synchrotron 4 while bending it to the rotating gantry 1. The high-energy beam transport device 5 is configured by combining the bending electromagnets 15B, the quadrupole electromagnets 16B, and the vacuum duct 17B.

[0039] As shown in FIG. 5, the high-energy beam transport device 5 has a first beam transport portion 5(1) that transports the charged particle beam substantially horizontally, and a second beam transport portion 5(2) that transports the charged particle beam substantially vertically. Figure 3 Further, the high-energy beam transport device 5 has a bending electromagnet 15B1 that bends the charged particle beam by 90 degrees between the first beam transport portion 5(1) and the second beam transport portion 5(2), and a bending electromagnet 15B2 that bends the charged particle beam by 90 degrees between the second beam transport portion 5(2) and the rotating gantry 1.

[0040] The first beam transport portion 5(1) is a structure in which the substantially linear vacuum duct 17B penetrates the quadrupole electromagnets 16B that control the convergence and / or divergence of the charged particle beam. The first beam transport portion 5(1) is installed to the ground via the stand 22 by fixing the quadrupole electromagnets 16B to the stand 22 provided on the ground.

[0041] The second beam transport section 5(2) is also a structure in which a substantially linear vacuum duct 17B penetrates the quadrupole electromagnet 16B, like the first beam transport section 5(1). The second beam transport section 5(2) is fixedly installed to the wall surface of the building 100 in a state in which the quadrupole electromagnet 16B is fixed to the stand 22. By fixing the second beam transport section 5(2) to the wall surface, it is possible to reduce the installation area thereof and stabilize the installation thereof.

[0042] The charged particle beam emitted from the synchrotron 4 is transported to the bending electromagnet 15B1 through the quadrupole electromagnet 16B and the vacuum duct 17B of the first beam transport section 5(1). For example, the traveling direction of the transported charged particle beam is substantially horizontal with respect to the ground, and the first beam transport section 5(1) is connected from the synchrotron 4 to the bending electromagnet 15B1 on a substantially straight line.

[0043] The charged particle beam transported from the first beam transport section 5(1) to the bending electromagnet 15B1 is bent by the bending electromagnet 15B1 in a direction away from the ground. At this time, for example, the bending angle of the bending electromagnet 15B1 is 90 degrees, and the direction toward which the bent charged particle beam is directed is a substantially vertical direction upward. The charged particle beam bent by the bending electromagnet 15B1 is injected into the second beam transport section 5(2). The second beam transport section 5(2) transports the injected charged particle beam to the bending electromagnet 15B2.

[0044] The bending electromagnet 15B2 bends the charged particle beam from the second beam transport section 5(2) in a direction toward the rotating gantry 1 and injects it into the rotating gantry 1. At this time, for example, the bending angle of the bending electromagnet 15B2 is 90 degrees, and the direction toward which the bent charged particle beam is directed is a direction that is substantially horizontal with respect to the ground and toward the synchrotron 4. In other words, the charged particle beam from the bending electromagnet 15B2 is directed in a direction opposite to the direction in which it is emitted from the synchrotron 4.

[0045] The connection point of the high-energy beam transport device 5 to the rotating gantry 1 is located on the rotation axis 30 of the rotating gantry 1, and the traveling direction of the charged particle beam injected from the high-energy beam transport device 5 to the rotating gantry 1 coincides with the rotation axis 30 of the rotating gantry.

[0046] Further, in the present embodiment, the case where the high-energy beam transport device 5 is provided with two steering electromagnets 15B1, 15B2 that steer the charged particle beam by 90 degrees is described as an example, but the present embodiment is not limited to this configuration. As another example, the number of steering electromagnets 15B can be one or more than three. Further, the steering angle of the steering electromagnets 15B is not limited to 90 degrees, and can be another angle. For example, the charged particle beam emitted from the synchrotron 4 can be steered in a plane that is substantially horizontal to the ground, and then be introduced into the steering electromagnet 15B1. Further, for example, the charged particle beam steered by the steering electromagnet 15B2 can be steered in a plane that is substantially horizontal to the ground, and then be introduced into the rotating gantry 1.

[0047] Further, in the present embodiment, the case where the first beam transport section 5(1) is installed to the floor and the second beam transport section 5(2) is installed to the wall surface using the stand 22 is described as an example, but the present embodiment is not limited to this configuration. As another example, one or both of the first beam transport section 5(1) and the second beam transport section 5(2) can be installed to the floor or the wall surface without using the stand 22.

[0048] Further, in the present embodiment, the first beam transport section 5(1) is installed to the floor and the second beam transport section 5(2) is installed to the wall surface, but the installation positions are not limited to this. For example, the second beam transport section 5(2) can be fixed to the support device 14.

[0049] The rotating gantry 1 is provided with a front ring 9, a rear ring 10, a rotating body 11, a support roller 12, a gantry rotation motor (not shown), a support device 14, and a gantry transport line 19.

[0050] The rotating body 11 is provided with a first cylindrical portion 11(1), a conical portion 11(2), and a second cylindrical portion 11(3) in this order from the front ring 9 side toward the rear ring 10 side. The front ring 9 and the rear ring 10 are connected by the first cylindrical portion 11(1). The front ring 9 side of the rotating body 11 is open, and a treatment booth 8 that is a space in which a patient is irradiated with a charged particle beam for treatment is provided on the inside of the rotating body 11 and the front ring 9 side. The gantry transport line 19 is fixed to the rotating body 11.

[0051] The support device 14 is installed to the same floor as the synchrotron 4. The support roller 12 is rotatably fixed to the support device 14. The front ring 9 and the rear ring 10 are mounted on the support roller 12. That is, the support device 14 supports the front ring 9, the rear ring 10, the rotating body 11, and the gantry transport line 19 via the support roller 12.

[0052] The support roller 12 is rotated by the power of the gantry rotation motor, and transmits the power to the front ring 9 and the rear ring 10, whereby the front ring 9, the rear ring 10, the rotating body 11, and the gantry transport line 19 become one body and rotate around the rotation axis 30.

[0053] Figure 5 is a view of a particle therapy system showing a state in which the rotating body is rotated. In the above Figures 1 to 4 is shown a particle therapy system in a state in which the irradiation nozzle 6 is capable of irradiating a charged particle beam to a patient placed on the treatment table 7 from the upper direction of the vertical direction. The rotating body 11 is capable of rotating approximately 360 degrees including this state. In Figure 5 is shown a state in which the rotating body 11 is rotated 90 degrees clockwise when viewed from the front, and the irradiation nozzle 6 is capable of irradiating a charged particle beam in the horizontal direction from the front side of the patient.

[0054] The gantry transport line 19 is a device that transports a charged particle beam injected from the high-energy beam transport device 5 to the irradiation nozzle 6 while being deflected. The gantry transport line 19 is rotatably connected to the high-energy beam transport device 5 at a connection point 20 on the rotation axis 30. The gantry transport line 19 is configured by combining a plurality of components including the deflection electromagnet 15C, the quadrupole electromagnet 16C, and the vacuum duct 17C.

[0055] The gantry transport line 19 makes a charged particle beam injected from the high-energy beam transport device 5 in the direction of travel along the rotation axis 30 pass through the inside of the second cylindrical portion 11(3), and is deflected by a deflection electromagnet (not shown) in a direction away from the rotation axis 30. The gantry transport line 19 transports the charged particle beam deflected in the direction away from the rotation axis 30 to the outside of the rotating body 11.

[0056] On the outside of the rotating body 11, a portion configured by the deflection electromagnet 15C1, the quadrupole electromagnet 16C, the vacuum duct 17C, and the deflection electromagnet 15C2 is installed to the outer peripheral surface of the first cylindrical portion 11(1). A charged particle beam that has reached the outside of the rotating body 11 is deflected by 135 degrees in a plane perpendicular to the rotation axis 30 by the deflection electromagnet 15C1, is controlled to expand the beam by the quadrupole electromagnet 16C, and is transported along the circumferential direction of the rotating body 11 by the vacuum duct 17C. The charged particle beam transported by the vacuum duct 17C is deflected by 135 degrees in a direction toward the rotation axis 30 in a plane perpendicular to the rotation axis 30 by the deflection electromagnet 15C2. The charged particle beam deflected in the direction toward the rotation axis 30 enters the inside of the rotating body 11, and is irradiated to a patient in the treatment room 8 via the irradiation nozzle 6.

[0057] By providing the gantry transport line 19 with the above-described structure, it is possible to shorten the length in the front-rear direction of the rotation axis 30 of the rotating gantry 1, and reduce the installation area of the particle therapy system. The installation area of the particle therapy system referred to here is the floor area required to install the particle therapy system.

[0058] Further, in the present embodiment, the gantry transport line 19 is shown to have a structure in which three steering electromagnets are provided, but the structure of the gantry transport line 19 is not limited to this. The number of steering electromagnets in the gantry transport line 19 can be less than three, or can be four or more. Further, in the present embodiment, the steering angles of the steering electromagnets 15C1, 15C2 are set to 135 degrees, but are not limited to this. The steering angles of the steering electromagnets 15C1, 15C2 can also be other angles. Further, the gantry transport line 19 can also have devices other than the steering electromagnets 15C, the quadrupole electromagnets 16C, and the vacuum duct 17C.

[0059] Further, in the present embodiment, a gantry transport line of a structure in which the convergence and / or divergence of the charged particle beam is controlled while being transported along the circumference of the rotating body 11 is exemplified, but is not limited to this structure. As another example, the gantry transport line 19 can also be configured to steer the charged particle beam that is injected from the high-energy beam transport device 5 in the advancing direction along the rotation axis 30 in a direction away from the rotation axis 30, to steer the charged particle beam that has been steered in the direction away from the rotation axis 30 in a direction substantially parallel to the rotation axis 30, and to steer the charged particle beam that has been steered in the direction substantially parallel to the rotation axis 30 in a direction toward the rotation axis 30.

[0060] The support device 14 is of a height such that the gantry transport line 19 does not come into contact with the synchrotron 4 or the first beam transport section 5(1) of the high-energy beam transport device 5 when the rotating gantry 1 is rotated such that the gantry transport line 19 is positioned below. More specifically, the height of the support device 14 from the ground is greater than the sum of the height of the synchrotron 4 or the high-energy beam transport device 5 from the ground of the facility and the height of the steering electromagnet 15C1 or the steering electromagnet 15C2 from the outer circumferential surface of the first cylindrical section 11(1), which is the maximum value.

[0061] By having the support device 14 of a sufficient height, the rotating gantry 1 and the synchrotron 4 can be disposed so as to overlap on the same ground surface, thereby enabling the ground surface area of the entire particle therapy system to be reduced. Further, in contrast to the conventional technique in which only the ground surface of the passage area of the gantry transport line is lowered in order to avoid contact with the ground surface, by having the support device 14 of a sufficient height, it is not necessary to lower the ground surface of the building 100, and the building 100 can be of a simple structure.

[0062] In the present embodiment, the support device 14 has four legs, and the rotating body 11 is supported by the four legs. In the present embodiment, the support device 14 is composed of a first support device 14(1) and a second support device 14(2). The first support device 14(1) and the second support device 14(2) each have an arch shape with two legs, and are arranged in the direction of the rotation axis 30. The first support device 14(1) is located on the front ring 9 side, and the second support device 14(2) is located on the rear ring side. The first support device 14(1) is disposed further forward than the steering electromagnet 15C1 and the steering electromagnet 15C2 of the gantry conveyance line 19. The second support device 14(2) is disposed further rearward than the steering electromagnet 15C1 and the steering electromagnet 15C2 of the gantry conveyance line 19. By thus composing the support device 14 of the first support device 14(1) on the front side and the second support device 14(2) on the rear side, it is possible to pass the gantry conveyance line 19, which rotates together with the rotating body 11, between the first support device 14(1) and the second support device 14(2) when the rotating body 11 rotates, and it is possible to avoid collision of the support device 14 and the gantry conveyance line 19. The first support device 14(1) supports the support rollers 12 that carry the front ring 9. The second support device 14(2) supports the support rollers 12 that carry the rear ring 10.

[0063] The first support device 14(1) is disposed such that one leg is disposed on the ground on the inner side of the circular ring of the synchrotron 4, and the other leg is disposed on the ground on the outer side of the circular ring, and the circular ring of the synchrotron 4 passes through the space between the legs of the first support device 14(1), passing through the arch-shaped space. In other words, the first support device 14(1) is disposed so as to straddle the circular ring of the synchrotron 4. In addition, the high-energy beam transport device 5 is disposed so as to pass through the space between the legs of the second support device 14(2), passing through the arch-shaped space. In other words, the second support device 14(2) is disposed so as to straddle the high-energy beam transport device 5. Thus, it is possible to dispose the synchrotron 4 and a part of the high-energy beam transport device 5 below the rotating body 11. It is possible to dispose the synchrotron 4 and / or the high-energy beam transport device 5 in a part of the support device 14 that does not contact the ground between a certain ground surface on which the support device 14 contacts the ground and another ground surface on which the support device 14 contacts the ground, and it is possible to reduce the installation area of the particle therapy system as a whole.

[0064] In particular, the charged particle beam emitted from the synchrotron 4 below the first support device 14(1) on the front side is transported toward the rear side through the space between the two legs of the second support device 14(2) by the high-energy beam transport device 5, and is transported upward on the rear side, and this configuration makes it possible to efficiently dispose the synchrotron 4 and the high-energy beam transport device 5 below the rotating body 11, and helps to reduce the installation area of the particle therapy system.

[0065] Further, the structure and arrangement of the support device 14 is not limited to the present embodiment. As long as the rotating body 11 is arranged at a higher position than at least one of the linear accelerator 2, the synchrotron 4, or the high-energy beam transport device 5, it is possible to further reduce the installation area of the entire particle therapy system. Further, by arranging the high-energy beam transport device 5 so as to extend in the substantially vertical direction, it is possible to reduce the installation area. However, it is not necessary to arrange the linear accelerator 2, the synchrotron 4, or the high-energy beam transport device 5 below the rotating body 11. By arranging the rotating body 11 at a higher position, it is possible to secure a space for arranging the control device, the power supply, and the like below the rotating body 11, and it is possible to reduce the installation area of the entire particle therapy system.

[0066] Further, in the present embodiment, the case where the support device has four legs is described as an example, but the number of legs is not limited to four, and can be three or less, or five or more. Further, in the present embodiment, the case where the first support device and the second support device are in the shape of an arch is described as an example, but the first support device 14(1) and the second support device 14(2) can be in a single structure, or a part or all of the legs can have different structures.

[0067] Further, the material of the support device 14 can be a metal such as iron, or a part or all of the support device 14 can be made of another material such as concrete. If the material of the support device 14 is a metal, it is possible to install the support device 14 after installing the synchrotron 4 and the high-energy beam transport device 5, and it is possible to easily install the synchrotron 4 and the high-energy beam transport device 5. On the other hand, by making the material of the support device 14 concrete and arranging the support device 14 between the control device (not shown) of the particle therapy system and the synchrotron 4 or the high-energy beam transport device 5, it is possible to function as a shielding wall for the control device.

[0068] Further, in the present embodiment, the case where the rotating gantry 1 rotates by substantially 360 degrees is described as an example, but the rotation angle can be 360 degrees or less, and other gantries such as a half gantry having a rotation angle of 300 degrees or less can be used.

[0069] The rotating gantry 1 has the above-described support device 14, whereby it is possible to arrange the devices so that the region in which the linear accelerator 2, the synchrotron 4, and the high-energy beam transport device 5 are arranged and the region in which the rotating gantry 1 is arranged are arranged in a superposed manner, and it is possible to reduce the installation area as a whole of the particle therapy system. In other words, it is possible to arrange the devices in such a manner that at least a part of the projection onto the floor of the linear accelerator 2, the synchrotron 4, and the high-energy beam transport device 5 and at least a part of the projection onto the floor of the rotating gantry 1 overlap, and it is possible to reduce the installation area as a whole of the particle therapy system.

[0070] The irradiation nozzle 6 is a device that processes the charged particle beam transported from the high-energy beam transport device 5 into an appropriate radiation dose distribution that matches the shape of the cancer tissue of the patient and irradiates the affected part. The irradiation nozzle 6 is attached to the rotating body 11 of the rotating gantry 1, and by rotating integrally with the rotating body 11 around the rotation axis 30, it is possible to irradiate the charged particle beam to the patient in the treatment booth 8 from an arbitrary direction.

[0071] Figure 6 is a view showing a state in which the particle therapy system is installed in a building.

[0072] The particle therapy system is installed in the building 100 that is a building, and a particle therapy facility is constituted by the particle therapy system and the building 100. In the building 100, an accelerator room 101 and a treatment room 102 are provided that are separated from each other by a treatment room wall 103. In the accelerator room 101, the linear accelerator 2, the synchrotron 4, the high-energy beam transport device 5, and the rotating gantry 1 are installed. In the treatment room 102, a treatment table 7 on which a patient is placed is provided. The treatment table 7 can enter and exit the treatment booth 8 from an opening of the treatment room wall 103.

[0073] The accelerator room 101 ensures a space at a rotation radius from the rotation axis 30 so that the rotating gantry 1 can rotate freely by approximately 360 degrees. In addition, by arranging the rotating gantry 1 in such a manner that the rotation axis 30 has an inclined angle with respect to the outer wall of the building 100, it is possible to use the space on the diagonal line of the building 100, and it is possible to further reduce the installation area. For example, as shown in Figure 2 , with respect to the substantially rectangular building 100, the rotation axis 30 is arranged in such a manner as to follow the diagonal line of the building 100.

[0074] In the present embodiment, an example in which the linear accelerator 2, the synchrotron 4, the high-energy beam transport device 5, and the rotating gantry 1 are installed in the accelerator room 101 is described, but it is not limited thereto, and for example, the linear accelerator 2 or the high-energy beam transport device 5 can be installed in another room outside the accelerator room 101. In addition, a control device (not shown) can be arranged in the accelerator room 101. At this time, a shielding wall between the synchrotron 4 and the control device can be installed in the accelerator room 101.

[0075] In the present embodiment, the synchrotron 4 is described as an example of an accelerator. The synchrotron 4 is capable of accelerating a charged particle beam to an arbitrary energy and emitting a charged particle beam of an arbitrary energy. On the other hand, a cyclotron and a synchrocyclotron, which are other accelerators, can only emit a charged particle beam accelerated to a maximum energy. In the cyclotron and the synchrocyclotron, the charged particle beam emitted at the maximum energy is passed through a device called a wedge to reduce the energy to an arbitrary value, and then irradiated to a patient. At this time, the wedge is radiated due to absorption of the energy. Therefore, in the case of the cyclotron, a thick radiation wall needs to be provided between a gantry on which the patient is placed and the accelerator in order to reduce the amount of radiation to the patient. On the other hand, the synchrotron 4, which does not need the wedge, does not need the radiation wall as in the cyclotron and the synchrocyclotron, and is capable of disposing the accelerator and the rotating gantry 1 in the same room.

[0076] By thus disposing the accelerator and the rotating gantry 1 in the same room, it is possible to suppress the height of the building 100, and to realize a small and low-cost particle therapy facility. However, the present embodiment is not limited to the synchrotron 4, and the effect of reducing the installation area can be obtained as long as it is an accelerator capable of emitting a charged particle beam of an arbitrary energy.

[0077] In addition, neutrons and the like generated from a circular or toroidal accelerator have a directional property toward the outer periphery of the circle. Since the treatment room 8 and the synchrotron 4 are not located on the same plane, the number of neutrons generated from the synchrotron 4 that are directed toward the patient on the treatment table 7 is small, and it is also possible not to make the floor of the treatment room 102 and the treatment room wall 103, such as a radiation wall, thick.

[0078] The floor level of the treatment room 102 is set in the vicinity of the rotation axis 30 of the space in which the radius of rotation is ensured, and is thus generally about 6 to 8 m higher than the floor level of the accelerator room 101.

[0079] In the present embodiment, the structure in which one rotating gantry 1 and one treatment room 102 are provided is described as an example, but the present embodiment is not limited thereto. Two or more rotating gantries 1 can be provided in the accelerator room 101, and the building 100 can be provided with two or more treatment rooms 102.

[0080] The above-described embodiments are examples for description, and are not intended to limit the scope of the present application to the embodiments. Those skilled in the art can implement the present application in other various ways without departing from the scope of the present application.

[0081] Symbol explanation

[0082] 1 - rotating gantry, 2 - linear accelerator, 3 - low energy beam transport, 4 - synchrotron, 5 - beam transport, 6 - irradiation nozzle, 7 - treatment table, 8 - treatment cell, 9 - front ring, 10 - rear ring, 11 - rotating body, 12 - support roller, 14 - support device, 15 - steering electromagnet, 16 - quadrupole electromagnet, 17 - vacuum duct, 19 - gantry transport line, 20 - connection point, 21 - high-frequency acceleration cavity, 22 - stand, 30 - rotation axis, 100 - building, 101 - accelerator room, 102 - treatment room, 103 - treatment room wall.

Claims

1. A particle beam irradiation system comprising: an accelerator provided on a floor and accelerating a charged particle beam; a transport device transporting the charged particle beam emitted from the accelerator; an irradiation device irradiating a subject with the charged particle beam transported by the transport device; and a gantry provided on the floor independently of the accelerator and mounting the irradiation device, wherein the particle beam irradiation system is characterized in that the gantry has: a rotating body rotating the irradiation device around the subject; and a support device supporting the rotating body from the floor at a position where a projection of the rotating body onto the floor and a projection of at least one of the accelerator or the transport device onto the floor at least partially overlap, and at least a portion of a material of the support device is metal.

2. The particle beam irradiation system according to claim 1, wherein the accelerator and the gantry are arranged in a room divided into one space.

3. The particle beam irradiation system according to claim 2, wherein the support device is in contact with the floor at a first grounding surface and a second grounding surface, and at least a portion of at least one of the accelerator or the transport device is arranged between the first grounding surface and the second grounding surface.

4. The particle beam irradiation system according to claim 1, wherein the transport device has: a first steering electromagnet upwardly steering the charged particle beam accelerated by the accelerator; and a second steering electromagnet steering the charged particle beam steered by the first steering electromagnet toward a direction of an axis of rotation of the rotating body.

5. The particle beam irradiation system according to claim 1, wherein the gantry further has a third steering electromagnet steering the charged particle beam outside a peripheral surface of the rotating body, and the support device has: a first support portion arranged at a position in front of the third steering electromagnet in a direction of the axis of rotation of the rotating body; and a second support portion arranged at a position behind the third steering electromagnet.

6. The particle beam irradiation system according to claim 1, wherein the gantry further has a transport line transporting the charged particle beam to outside the peripheral surface of the rotating body, and a height of the support device is greater than a sum of a height of the transport line from the peripheral surface of the rotating body and a height of at least one of the accelerator or the transport device from the floor.

7. The particle beam irradiation system according to claim 1, wherein a portion of the transport device is fixed to a wall surface of a room in which the particle beam irradiation system is provided.

8. The particle beam irradiation system according to claim 1, wherein the gantry further has a transport line transporting the charged particle beam transported by the transport device to outside the peripheral surface of the rotating body, transporting along a circumferential direction of the rotating body, and transporting toward a direction of an axis of rotation of the rotating body.

9. The particle beam irradiation system according to claim 1, wherein the accelerator is a synchrotron accelerator accelerating the charged particle beam through a ring-shaped path. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10. The particle beam irradiation system according to claim 1, wherein at least a part of the material of the support device is concrete.

11. The particle beam irradiation system according to claim 1, wherein the transport device has a first beam transport section that transports the charged particle beam accelerated by the accelerator along the floor, and a second beam transport section that transports the charged particle beam upward downstream of the first beam transport section, the support device has the second beam transport section located at the back, straddles the first beam transport section with two legs, and contacts the floor.

12. A particle beam irradiation system comprising: an accelerator provided on a floor and accelerating a charged particle beam; a transport device that transports the charged particle beam emitted from the accelerator; an irradiation device that irradiates a charged particle beam transported by the transport device to an irradiation target; and a gantry provided on the floor independently of the accelerator and mounting the irradiation device, the particle beam irradiation system being characterized in that the gantry has: a rotating body that rotates the irradiation device around the irradiation target; and a support device that supports the rotating body from the floor at a position where a projection of the rotating body onto the floor and a projection of at least one of the accelerator or the transport device onto the floor overlap, the accelerator is a synchrotron accelerator that accelerates the charged particle beam through a ring-shaped path, in the support device, has a first leg and a second leg, and straddles the ring-shaped path with the first leg located inside the ring-shaped path and the second leg located outside the ring-shaped path, and contacts the floor.

13. The particle beam irradiation system according to claim 12, wherein the transport device has a first beam transport section that transports the charged particle beam accelerated by the accelerator along the floor, and a second beam transport section that transports the charged particle beam upward downstream of the first beam transport section, the support device has the second beam transport section located at the back, straddles the first beam transport section with two legs, and contacts the floor.

14. The particle beam irradiation system according to claim 12, wherein at least a part of the material of the support device is metal.

15. The particle beam irradiation system according to claim 12, wherein at least a part of the material of the support device is concrete.

16. A particle beam irradiation facility, characterized by comprising: a building; and the particle beam irradiation system according to any one of claims 1 to 15 provided in the building.

17. The particle beam irradiation facility according to claim 16, wherein the irradiation target is a patient, further comprising a partition wall provided between a treatment room provided with a treatment table on which the patient is placed and which can be entered into the rotating body, and a room provided with the accelerator and the gantry. ​

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