JP2020069085A - Particle beam irradiation system - Google Patents

Abstract

To provide a particle beam irradiation system that has improved weight balance of a rotating part.SOLUTION: A particle beam irradiation system includes: a placing base on which an irradiation object is placed; a straight line accelerator for generating a charged particle beam in a straight path; an accelerator for accelerating the charged particle beam generated by the straight line accelerator; a transport device for transporting the charged particle beam emitted from the accelerator; an irradiation device for irradiating the charged particle beam transported by the transport device; and a gantry in which the transport device and the irradiation device are installed, and which rotates the irradiation device around the irradiation object. The accelerator is installed in the gantry so that the center of the accelerator is located on a side opposite to the transport device with respect to a rotation shaft of the gantry.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a particle beam irradiation system capable of rotating an irradiation nozzle that irradiates a particle beam.

  Conventionally, radiations such as X-rays, gamma rays, electron rays and fast neutron rays have been used for cancer treatment. However, these radiations have a maximum radiation dose on the surface of the body before reaching the affected area within the body of the patient. Therefore, when treating a cancer in the deep part of the body, there is an adverse effect of damaging normal tissues on the surface of the body or in the vicinity thereof.

  On the other hand, there is a technique of using a particle beam for cancer treatment. The particle beam obtained by accelerating to high energy using an accelerator can maximize the radiation dose to the cancer existing in a certain position in the deep part of the body, and the particle beam can reach the deep part. The normal tissue that penetrates is characterized by being less likely to be damaged.

  In order to efficiently perform such treatment with a particle beam, it is necessary to accurately irradiate the affected part in the deep part of the patient's body with the charged particle beam. Therefore, a particle beam therapy system has been developed in which an irradiation nozzle for irradiating a charged particle beam can be driven so that the charged particle beam can be irradiated at an appropriate position from a suitable angle.

  Patent Document 1 discloses a particle beam irradiation apparatus capable of driving an irradiation nozzle. The particle beam irradiation apparatus disclosed in Patent Document 1 has a structure that realizes downsizing of the apparatus, and an injection accelerator for accelerating charged particles generated by an ion source and a charged particle beam sent from the injection accelerator to a predetermined size. An annular accelerator for accelerating to energy, and an irradiation field forming unit for forming an irradiation field for irradiating the irradiation target with the charged particle beam emitted from the annular accelerator, and the annular accelerator, the incident accelerator, and the irradiation field formation. The unit and the irradiation unit rotate about the same rotation axis.

JP, 2016-115477, A

  In the particle beam irradiation apparatus of Patent Document 1, the beam transporting means for guiding the charged particle beam emitted from the annular accelerator to the irradiation field forming device is between the annular accelerator and the irradiation field forming unit. This beam transport means also rotates around the same rotation axis as the annular accelerator or the like. That is, the beam transportation means is also included in the system that rotates around the rotation axis. Since this beam transport means is configured to include a heavy deflection electromagnet, it affects the weight balance of the system rotating around the rotation axis.

Therefore, the particle beam irradiation apparatus of Patent Document 1 employs a configuration in which a rotating shaft is arranged at the center of the annular accelerator and the weight is balanced by a counterweight. Although the counterweight is originally not directly related to the treatment, it is indispensable to balance the weight with the deflection electromagnet of the beam transportation means, and contributes to an increase in manufacturing and installation costs.
It is an object of the present invention to provide a particle beam irradiation system with improved weight balance of rotating parts.

  A particle beam irradiation system according to one aspect of the present disclosure includes a mounting table on which an irradiation target is mounted, a linear accelerator that generates a charged particle beam in a linear path, and an accelerator that accelerates the charged particle beam generated by the linear accelerator. A transportation device for transporting the charged particle beam emitted from the accelerator, an irradiation device for irradiating the charged particle beam transported by the transportation device, the transportation device and the irradiation device, and the irradiation device. A gantry for rotating the gantry around the irradiation target, wherein the accelerator is arranged on the gantry such that the center of the accelerator is located on the side opposite to the transport device with respect to the rotation axis of the gantry. is set up.

  According to one aspect of the present disclosure, it is possible to provide a particle beam irradiation system in which the weight balance of rotating parts is improved.

It is a conceptual diagram for demonstrating the beam path structure of a particle beam irradiation system. It is a conceptual diagram for demonstrating the structure of a synchrotron. It is a conceptual diagram which shows the basic composition of a particle beam therapy system, and the installation state in a building. It is a perspective view of a particle beam therapy system. It is a right sectional view of a particle beam therapy system. It is a rear view of a rotating gantry. It is a rear view of the rotating gantry rotated from the state of FIG.

  Embodiments of the present invention will be described with reference to the drawings.

  Here, as an example of a particle beam irradiation system for irradiating an irradiation target with a particle beam, a particle beam therapy system for irradiating a cancer tissue of a cancer patient with the particle beam will be described.

  1A and 1B are conceptual diagrams for explaining the beam path configuration of the particle beam irradiation system. FIG. 1 shows a simplified two-sided view of an apparatus that constitutes a path of a particle beam in a particle beam therapy system S. FIG. 1A is a front view of the synchrotron 4, and FIG. 1B is a side view. In FIG. 1 (a) and FIG. 1 (b), the alternate long and short dash line represents the same height. The particle beam is emitted, accelerated, transported, and irradiated along this path.

  The beam path includes a linear accelerator 2, a low energy beam transport device 3, a synchrotron 4, a beam transport device 5, and a radiation irradiation nozzle 6.

  The linear accelerator 2 includes an ion source and a linear accelerator. The ion source generates charged particles by colliding a high-speed electron with a neutral gas and accelerates the charged particle beam by a linear accelerator to a state where it can be accelerated by the synchrotron 4. It is a device that emits toward. Here, the charged particle beam includes, for example, hydrogen, helium, carbon, nitrogen, oxygen, neon, silicon, and argon as the charged particles.

  The low energy beam transport device 3 is a device that is maintained in a high vacuum and transports the charged particle beam emitted from the linear accelerator 2 to the synchrotron 4.

  The synchrotron 4 is a device that is transported from the low-energy beam transport device 3 and efficiently accelerates the incident charged particle beam to an energy (about 70 MeV to 220 MeV) suitable for treating cancer. The synchrotron 4 has a deflection electromagnet 15A that deflects the charged particle beam and a vacuum duct 17A that is a path of the charged particle beam, and these are connected to each other to form an annular path in a plane. The charged particle beam is accelerated while orbiting an annular path. Details of the synchrotron 4 will be described later.

  The beam transport device 5 is a device that transports the charged particle beam accelerated by the synchrotron 4 to the radiation irradiation nozzle 6. The beam transport device 5 has a bending electromagnet 15B and a vacuum duct 17B, which are connected to each other to form a U-shaped path. The charged particle beam emitted outward from the annular path of the synchrotron 4 is deflected, for example, by the deflection electromagnet 15B in the direction orthogonal to the plane of the synchrotron 4, and is transported to the next deflection electromagnet 15B through the vacuum duct 17B. Then, the deflecting electromagnet 15B deflects the synchrotron 4 inwardly and sends it to the radiation irradiation nozzle 6. In the present embodiment, the beam transporting device 5 including two deflection electromagnets 15B for deflecting the charged particle beam by 90 degrees will be described as an example. However, the number of the deflection electromagnets 15B is not limited to two, and more than that. It may be less than that. Further, the beam transportation device 5 may include other devices such as a quadrupole magnet in addition to the deflection electromagnet 15B and the vacuum duct 17B.

  The radiation irradiation nozzle 6 is a device that processes the charged particle beam transported from the beam transport device 5 into a suitable dose distribution according to the shape of the cancer tissue of the patient and irradiates the affected area.

  The charged particle beam generated and emitted by the linear accelerator 2 is sent to the low energy beam transport device 3 via the connection point 20. The low energy beam transport device 3 has an incident deflector. The charged particle beam is deflected by the incident deflector and is incident on the synchrotron 4 which is the main accelerator. The charged particle beam sufficiently accelerated by the synchrotron 4 up to the energy required for treatment (usually 70 to 220 MeV for protons) is deflected again by the deflection electromagnet 15B of the beam transport device 5 and transported to the radiation irradiation nozzle 6. To be done. Thereafter, the charged particle beam is processed by the radiation irradiation nozzle 6 into a dose distribution suitable for cancer treatment, and is irradiated onto the isocenter 18.

  A quadrupole electromagnet 16 (not shown) is arranged in the path of the charged particle beam at an appropriate interval to control the horizontal and vertical convergence and / or divergence of the transported charged particle beam.

  Further, the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 are installed in a rotating gantry 1 (not shown), and as one rotating system, a straight line connecting the isocenter 18 and the connection point 20 is used as a rotating shaft 30 to rotate the same. It rotates integrally around the axis 30. This makes it possible to irradiate the isocenter 18 with the charged particle beam from the radiation irradiation nozzle 6 from various angles.

  Here, the circular path of the synchrotron 4, that is, the center 31 of the orbit of the charged particle beam does not coincide with the rotation axis 30 of the rotating system. The center 31 of the annular path is in a direction (downward in FIG. 1) opposite to the beam transport device 5 with respect to the rotation axis 30. In other words, when viewed from the front of the synchrotron 4, the center 31 is at a position facing the beam transport device 5 with the rotary shaft 30 interposed therebetween. As a result, the weight balance of the rotary system including the synchrotron 4 and the beam transport device 5 is improved, and the counterweight conventionally required is no longer necessary. For example, if importance is attached to facilitating rotation of the rotating system, the rotating shaft 30 is attached to the center of gravity (not shown) of the rotating system including the gantry 1, the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 and rotating integrally. It is advantageous to match. It is stable whether the rotating system is stationary or rotating. In consideration of stability against earthquakes and the like when the system is stopped, the rotating shaft 30 is located between the center 31 of the annular path and the center of gravity of the rotating system, and the particle beam irradiation system S is The beam transport device 5 is preferably arranged above the synchrotron 4 when not in use.

FIG. 2 is a conceptual diagram for explaining the configuration of the synchrotron.
As shown in FIG. 2, the synchrotron 4 includes a deflection electromagnet 15A, a quadrupole electromagnet 16 and a vacuum duct 17A, and forms an annular path. Although not shown, a high-frequency applying cavity is also provided on the annular path to accelerate the circulating charged particle beam. In the example of FIG. 2, four deflection electromagnets 15A for deflecting the charged particle beam by 90 degrees are arranged at four corners, a vacuum duct 17A for passing the charged particle beam through the deflection electromagnet 15A penetrates, and an annular path is formed. I am configuring. The quadrupole electromagnet 16 suppresses horizontal and vertical focusing and / or divergence of the charged particle beam. Although FIG. 2 shows a configuration in which four deflection electromagnets 15A and four quadrupole electromagnets 16 are arranged in an annular path, the configuration of the synchrotron 4 is not limited to this. The deflection electromagnets 15A may be provided in less than four, or five or more. Further, less than four quadrupole electromagnets 16 may be provided, or five or more quadrupole electromagnets 16 may be provided. Further, other devices such as the bending electromagnet 15A, the quadrupole electromagnet 16, and the high-speed acceleration cavity may be provided on the annular path, or at the connection portion with the low energy transportation system 3 or the connection portion of the beam transportation device 5.

  The synchrotron 4 accelerates the charged particle beam in an annular path, increasing the energy required to treat cancer. The charged particle beam accelerated by the synchrotron 4 is sent to the beam transport device 5.

FIG. 3 is a conceptual diagram showing a basic configuration of the particle beam therapy system and an installation state in a building.
FIG. 4 is a perspective view of the particle beam therapy system. FIG. 5 is a right sectional view of the particle beam therapy system. The right side here is the right side when the particle beam treatment system S is viewed from the side of the treatment cage 8. FIG. 5 shows the particle beam therapy system S cut along a vertical plane parallel to the rotation axis 30 so that the internal structure of the rotation gantry 1 can be seen.
The building 100 is provided with a treatment room 101 and a gantry room 102 which are separated from each other by a partition wall 103. The particle beam therapy system S is generally installed in the gantry chamber 102, and the treatment table 7 on which the patient is placed can enter and leave the treatment cage 8 through the opening of the partition wall 103.

  The gantry chamber 102 is provided with a space having a radius of rotation from the rotary shaft 30 so that the rotary gantry 1 can freely rotate about 360 degrees. Since the floor level of the treatment room 101 is set in the vicinity of the rotating shaft 30 which secures a space of the turning radius, it is usually a position higher by about 6 to 8 m than the floor level of the gantry room 102.

  The rotating gantry 1 is a structure including a front ring 9, a rear ring 10, and a gantry body 11 and having a cylindrical portion coaxially coupled to each other. A synchrotron 4 having a deflection electromagnet 15A and a vacuum duct 17A, a beam transport device 5 having a deflection electromagnet 15B and a vacuum duct 17B (not shown), and a radiation irradiation nozzle 6 are fixedly installed on the rotating gantry 1. It is a rotating system. A plurality of or all of the devices forming the rotary system may be modularized. By completing the module at the factory, on-site installation work can be shortened and facilitated.

  Below the rotating gantry 1, a drive unit including a support roll 12 and a gantry rotation motor 13 connected to the support roll 12 is arranged. The front ring 9 and the rear ring 10 of the rotating gantry 1 are mounted on the support roll 12. The support roll 12 is rotated by the power of the gantry rotation motor 13, and the power is transmitted to the front ring 9 and the rear ring 10 to rotate the rotating gantry 1. As a result, the rotating gantry 1 rotates around the rotation axis 30 together with the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6.

  The synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 rotate integrally around the rotation axis 30 while maintaining the irradiation direction of the charged particle beam from the radiation irradiation nozzle 6 toward the patient on the treatment table 7. Will be done.

  The linear accelerator 2 is arranged in the rear ring 10 of the rotating gantry 1, but is not fixed to the rotating gantry 1 but is fixed to the building 100. Therefore, the linear accelerator 2 does not rotate even if the rotating gantry 1 rotates.

  The synchrotron 4 is installed on the gantry body 11 by the synchrotron installation seat 14, and forms an annular path in a plane orthogonal to the height direction of the cylindrical rotating gantry 1. A beam transport device 5 is installed on the outer peripheral surface of the cylindrical portion of the rotating gantry 1, receives the charged particle beam from the synchrotron 4, deflects it by 90 degrees, and transports it in the same direction as the axis of the cylindrical portion. It is deflected once and sent to the radiation irradiation nozzle 6. In the example of FIG. 3, a quadrupole electromagnet 16 is also provided between the beam transport device 5 and the radiation irradiation nozzle 6. The radiation irradiating nozzle 6 is fixed to the treatment table 7 in the treatment gauge 8 downstream of the beam transport device 5 with respect to the traveling direction of the charged particle beam, and irradiates the isocenter 18 with the charged particle beam. As shown in FIG. 1, the radiation irradiation nozzle 6 has a length such that the tip thereof does not reach the rotating shaft 30, and irradiates the charged particle beam transported by the beam transport device 5 from the tip of the nozzle.

  The treatment table 7 is attached to the treatment room 101, and in order to irradiate the affected area with the charged particle beam adjusted by the radiation irradiation nozzle 6 from around 360 degrees of the patient, the plane direction and the height direction can be adjusted appropriately. It has a movable mechanism.

  As shown in FIG. 5, the linear accelerator 2 is fixed to the floor surface protruding from the building 100, and is rotatably connected to the synchrotron at a connection point 20 arranged on the rotating shaft 30. There is. Therefore, the linear accelerator 2 does not rotate even if the rotating gantry 1 rotates. The linear accelerator 2 is connected to a waveguide having a hollow structure that is bent to transfer high-frequency charged particles to the acceleration tube of the synchrotron 4 and a large power source. Therefore, the linear accelerator 2 is not included in the rotary system but is fixed to the floor surface of the building 100. As a result, the linear accelerator 2 can be installed by the same installation method as that of a conventional system having a large number of operating records, and a stable supply of charged particles can be expected. Further, by installing the linear accelerator 2 so that the connection point 20 is located on the rotary shaft 30, even if the rotary shaft 30 and the center 31 do not coincide with each other, the connection point 20 does not expand and contract, and a simple structure can be obtained. ..

  On the other hand, as shown in FIGS. 4 and 5, the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 are fixed to the rotating gantry 1 in which the front ring 9, the gantry body 11, and the rear ring 10 are connected. And rotates with the rotating gantry 1. The rotating gantry 1 has a structure in which the front ring 9 and the rear ring 10 mounted on a plurality of support rolls 12 and a gantry rotation motor 13 connected to the support rolls rotate the entire structure by about 360 degrees.

  The charged particle beam emitted from the linear accelerator 2 is deflected and twisted by an incident deflector (not shown) when passing through the low energy beam transport device 3, and is incident on a synchrotron 4 which is a main accelerator.

  The synchrotron 4 is fixedly installed on a flat synchrotron installation seat 14. The annular path of the synchrotron 4 is arranged in a plane parallel to the synchrotron seat 14. The synchrotron installation seat 14 is installed perpendicularly to the rotating shaft 30 of the rotating gantry 1.

  The synchrotron installation seat 14 and the synchrotron 4 are fixed to the rotating gantry 1 at positions eccentric to a direction in which the weight balance of the rotating gantry 1 on which the beam transport device 5 is mounted is improved. In this embodiment, the beam transport device 5 is mounted on the rotating gantry 1, and the center 31 of the orbit of the synchrotron 4 is eccentric to the opposite side of the rotating shaft 30 from the beam transport device 5. As a result, regardless of whether the rotating gantry 1 is stationary at the standard position, is stationary at a position rotated at an arbitrary angle, or is rotating, the rotating system of the rotating system can be operated without using the counterweight. A good weight balance is achieved.

  The charged particle beam accelerated by the synchrotron 4 is deflected 180 degrees by the two deflection electromagnets 15B when passing through the beam transport device 5 on the rotating gantry 1, and is transported to the radiation irradiation nozzle 6. The radiation irradiation nozzle 6 is equipped with monitors (not shown) for monitoring the dose of the charged particle beam and the passing position. The radiation irradiating nozzle 6 processes the charged particle beam into a dose distribution suitable for treatment while observing the dose and the passing position with monitors, and irradiates a patient (not shown) on the treatment table 7.

  As shown in FIG. 4, the treatment table 7 installed in the building 100 is arranged in a plane direction so that the treatment table 7 can be inserted from an opening at one end of the cylindrical portion of the rotating gantry 1 to a predetermined position inside the cylindrical portion. A movable mechanism including a robot arm capable of appropriately adjusting the height direction is provided, and the charged particle beam adjusted by the radiation irradiation nozzle 6 can be accurately irradiated to the affected area from around 360 degrees of the patient. Further, the treatment table 7 is arranged at a position where the plane on which the annular path of the synchrotron 4 is formed does not intersect with the patient. In other words, the synchrotron 4 is arranged closer to the other end than the predetermined position into which the treatment table 7 of the cylindrical portion of the rotating gantry 1 can enter. As a result, the direction of the charged particles accelerated in the annular path of the synchrotron 4 does not directly face the patient on the treatment table 7, and the risk of unnecessary exposure of the patient is suppressed.

  FIG. 6 is a rear view of the rotating gantry. FIG. 7 is a rear view of the rotating gantry rotated from the state of FIG. The back surface here is the side on which the linear accelerator 2 is installed. 6 and 7, the rear ring 10 which is a part of the rotating gantry 1 is not drawn so that the state of rotation can be clearly understood. The linear accelerator 2 installed in the building 100 is not drawn for the same reason.

  As described above, the rotating gantry 1 is rotatable about the rotating shaft 30 by approximately 360 degrees. When the rotating gantry 1 rotates at an arbitrary angle (for example, the gantry rotation angle 315 degrees), the synchrotron 4 installed on the synchrotron installation seat 14 on the rotating gantry 1 rotates in synchronization with the rotating gantry 1. Therefore, the positional relationship with respect to the beam transport device 5 on the rotating gantry 1 is unchanged. Therefore, the synchrotron 4 whose center of the orbit is eccentric to the side of the rotating shaft 30 opposite to the deflecting electromagnet 15B of the beam transporting device 5 can serve as a counterweight regardless of the angle of the rotating gantry 1.

  The present embodiment described above includes the following matters. However, the disclosure of the present embodiment is not limited to the items shown below.

  The synchrotron 4, which is an annular accelerator, the beam transport device 5, and the radiation irradiation nozzle 6 maintain the irradiation direction of the charged particle beam from the radiation irradiation nozzle 6 in the direction of the patient who is the irradiation target, and around the rotation axis 30. Rotate as one. Therefore, the rotating system including the annular accelerator, the transportation device, and the irradiation device fixedly connected to each other rotates around the rotation axis that is eccentric in the direction in which the transportation device is located from the center of the annular accelerator, so that the weight balance of the rotating system is improved. To be done.

  In addition, the beam transport device 5 transports the charged particle beam emitted from the synchrotron 4 in the radial outside direction of the synchrotron 4, and then deflects the charged particle beam inward in the radial direction of the synchrotron 4 and transports it to the radiation irradiation nozzle 6. The radiation irradiating nozzle 6 has a length such that the tip thereof does not reach the rotating shaft 30, and irradiates the charged particle beam transported by the beam transporting device 5 from the tip of the nozzle. The rotating shaft 30 is located closer to the beam transport device 5 than the center of the annular path. Since the radiation irradiation nozzle 6 has a length that does not reach the rotation axis 30, the radiation irradiation nozzle 6 can be configured with a short length. By shortening the radiation irradiating nozzle 6, it is expected that the adjustment accuracy of the irradiation direction is improved.

  Further, the linear accelerator 2 is fixed to the building 100 and is rotatably connected to the synchrotron 4 at a connection point 20 arranged on the rotating shaft 30. Therefore, the linear accelerator 2 including the pipe of the linear path and connected to various peripheral devices can be fixedly installed (for example, on the floor) in the building 100. Therefore, it is possible to reduce the risk that an error will occur in the pipe positioned on the straight path. In addition, the weight balance design is facilitated by not including the linear accelerator 2 with the peripheral equipment, which is not easy to consider the weight in advance in the weight balance design, in the rotary system. It is also expected to improve the weight balance of the rotating system.

  Further, the rotating gantry 1 has a cylindrical portion coaxial with the rotating shaft 30, the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 are mounted and rotates around the rotating shaft 30. The treatment table 7 is installed so as to be able to enter from an opening at one end of the cylindrical portion to a predetermined position inside the cylindrical portion. On the other hand, the synchrotron 4 is installed on the other end side of the predetermined position into which the treatment table 7 of the cylindrical portion can enter. Therefore, the space for irradiating the patient with the particle beam and the rotary system for relatively fixing the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 are efficiently realized by the bottomed cylindrical portion. be able to.

  Further, the beam transport device 5 deflects the charged particle beam emitted from the linear accelerator 2 by about 180 degrees by one or a plurality of deflection electromagnets 15B mounted on the outer peripheral surface of the cylindrical portion of the rotating gantry 1, and the radiation irradiation nozzle 6 The synchrotron 4 is mounted on the rotating gantry 1 with the center of the trajectory of the charged particle beam eccentric to the side opposite to the side on which the deflection electromagnet 15B is attached with respect to the rotating shaft 30. There is.

  The rotary shaft 30 is located between the center of the synchrotron 4 and the position of the center of gravity of the rotary system that includes the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 and rotates integrally. When the particle beam irradiation system S is not used, the beam transport device 5 is arranged above the synchrotron 4. Therefore, in the stopped state, the rotary shaft 30 is set above the position of the center of gravity of the rotary system, so that the position of the rotary system can be stabilized. For example, it is possible to prevent the rotating system from rotating under its own weight when there is a large earthquake.

  However, the rotating shaft 30 may be aligned with the center of gravity of the rotating system that includes the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 and rotates integrally. In that case, the weight can be more balanced and the rotary system can be rotated with a small driving force.

  Although the linear accelerator 2 does not rotate together with the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 in the present embodiment described above, the present invention is not limited to this. As another example, the linear accelerator 2 may rotate together with the synchrotron 4, the beam transport device 5, and the irradiation nozzle 6.

  Further, in the present embodiment, an example in which the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 are installed in the rotating gantry has been shown, but the present invention is not limited to this. As another example, a power supply, a cable, a control device, etc. may be installed in the rotating gantry 1.

  Further, in the present embodiment, an example in which the rotary shaft 30 of the rotary system including the synchrotron 4, the beam transport device 5, and the radiation irradiation nozzle 6 is orthogonal to the plane including the annular path of the synchrotron 4, has been shown. It is not limited to. As another example, the plane including the rotating shaft 30 and the annular path of the synchrotron 4 may be at an angle other than 90 degrees (for example, 80 degrees). In that case, when the rotating system rotates, the plane including the annular path of the synchrotron 4 changes. Even in that case, even if the rotation system is at any rotation angle, if the treatment table 7 is installed so that the patient does not intersect with the plane including the annular path of the synchrotron 4, unnecessary exposure of the patient will occur. The risk can be suppressed.

  Further, in the present embodiment, the synchrotron is shown as an example of the accelerator that accelerates the charged particle beam generated by the linear accelerator 2 in a predetermined plane, but the present invention is not limited to this. As another example, other circular accelerators such as a cyclotron and a synchrocyclotron can be similarly applied. In the case of a circular accelerator, the center 31 of the annular path can be read as the center 31 of the circle.

  Further, the center 31 may be read as the center 31 of the annular path, the center 31 of the synchrotron 4, the center 31 of the accelerator 1, the center of gravity 31 of the accelerator, the center 31 of the orbit of the accelerator, and the center 31 of the acceleration orbit surface of the accelerator. it can.

  Further, in the present embodiment, the synchrotron 4 is installed on the synchrotron installation seat 14, and the synchrotron 4 is installed on the rotary gantry 1 by fixing the synchrotron installation seat 14 to the rotary gantry 14. The installation method of the tron 4 is not limited to this. For example, the synchrotron 4 may be directly fixed to the rotating gantry 1.

  Further, in the present embodiment, an example in which the synchrotron 4 is fixed to the back surface of the rotating gantry 1 has been shown, but the present invention is not limited to this. As another example, a thinktroton 4 or other accelerator may be installed behind the patient (closer to the back than the patient) inside the rotating gantry 1. Further, as another example, the synchrotron 4 may be installed on the side surface of the cylindrical rotating gantry 1.

  Further, in the present embodiment, the example in which the rotating gantry 1 has a cylindrical shape is shown, but a rectangular parallelepiped shape or a truss structure may be used. Furthermore, in the present embodiment, an example in which the rotating gantry 1 rotates about 360 degrees has been shown, but other gantry such as a half gantry having a rotation angle of 300 degrees or less may be used.

DESCRIPTION OF SYMBOLS 1 ... Rotating gantry, 2 ... Linear accelerator, 3 ... Low energy beam transport device, 4 ... Synchrotron, 5 ... Beam transport device, 6 ... Radiation irradiation nozzle, 7 ... Treatment table, 8 ... Treatment cage, 9 ... Front ring, 10 ... Rearing, 11 ... Gantry body, 12 ... Support roll, 13 ... Gantry rotation motor, 14 ... Synchrotron installation seat, 15A ... Bending electromagnet, 15B ... Bending electromagnet, 16 ... Quadrupole electromagnet, 17A ... Vacuum duct, 17B ... Vacuum duct, 18 ... Isocenter, 20 ... Connection point, 30 ... Rotation axis, 31 ... Center, 100 ... Building, 101 ... Treatment room, 102 ... Gantry room, 103 ... Partition wall

Claims (9)

A mounting table on which the irradiation target is mounted,
A linear accelerator that generates a charged particle beam in a linear path,
An accelerator for accelerating the charged particle beam generated by the linear accelerator;
A transport device for transporting the charged particle beam emitted from the accelerator,
An irradiation device for irradiating the charged particle beam transported by the transport device,
A gantry in which the transport device and the irradiation device are installed, and the irradiation device is rotated around the irradiation target,
Have
The accelerator is installed in the gantry such that the center of the accelerator is located on the side opposite to the transportation device with respect to the rotation axis of the gantry.
Particle beam irradiation system. The accelerator, the transport device, and the gantry rotate together.
The particle beam irradiation system according to claim 1. The linear accelerator is fixed with respect to the building,
The particle beam irradiation system according to claim 1. The connection point is arranged on the rotation axis,
The particle beam irradiation system according to claim 3. The gantry has a cylindrical portion coaxial with the rotation axis,
The mounting table is installed so as to be able to enter from an opening at one end of the cylindrical portion to a predetermined position inside the cylindrical portion,
The accelerator is installed on the other end side of the predetermined position into which the mounting table of the cylindrical portion can enter.
The particle beam irradiation system according to claim 1. The transporting device deflects the charged particle beam emitted from the linear accelerator by approximately 180 degrees by one or a plurality of deflection electromagnets mounted on the outer peripheral surface of the cylindrical portion of the gantry and makes it enter the irradiation device. ,
The linear accelerator is mounted on the rotating gantry with the center of the trajectory of the charged particle beam eccentric to the side opposite to the side on which the deflection electromagnet is attached with respect to the rotation axis.
The particle beam irradiation system according to claim 5. The rotation axis is between the center of the accelerator and the position of the center of gravity of a rotating system that integrally rotates including the accelerator, the transport device, and the irradiation device,
The particle beam irradiation system according to claim 1. The rotation axis coincides with the center of gravity of a rotation system that integrally rotates including the accelerator, the transportation device, and the irradiation device,
The particle beam irradiation system according to claim 1. The accelerator is a synchrotron,
The particle beam irradiation system according to claim 1.

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