Neutron capture therapy system

Abstract

The present application provides a neutron capture therapy system, comprising a neutron generating device and a beam shaping body, the neutron capture therapy system further comprising a concrete wall forming a space accommodating the neutron generating device and the beam shaping body and shielding radiation generated by the neutron generating device and the beam shaping body, a support module being arranged in the concrete wall, the support module being capable of supporting the beam shaping body and being used for adjusting a position of the beam shaping body, the support module comprising concrete and a reinforcing part arranged at least partially in the concrete. The neutron capture therapy system of the present application designs a locally adjustable support for the beam shaping body, so that the beam shaping body meets the accuracy requirement, improves the beam quality and meets the assembly tolerance of the target.

Description

TECHNICAL FIELD

[0001] The present application relates to a radiation irradiation system, in particular to a neutron capture therapy system. BACKGROUND

[0002] With the development of atomic science, radiotherapy such as cobalt-60, linear accelerator, electron beam, etc. has become one of the main means of cancer treatment. However, traditional photon or electron therapy is limited by the physical conditions of the radiation itself, which not only kills tumor cells but also causes damage to a large number of normal tissues along the beam path; in addition, due to the different sensitivity of tumor cells to radiation, the treatment effect of traditional radiotherapy on malignant tumors with high radiation resistance (such as glioblastoma multiforme and melanoma) is often poor.

[0003] In order to reduce the radiation damage to normal tissues around the tumor, the concept of targeted therapy in chemotherapy is applied to radiotherapy; and for tumor cells with high radiation resistance, radiation sources with high relative biological effectiveness (RBE) are actively developed, such as proton therapy, heavy particle therapy, and neutron capture therapy. Among them, neutron capture therapy combines the above two concepts, such as boron neutron capture therapy, which provides a better choice for cancer treatment than traditional radiotherapy by specific accumulation of boron-containing drugs in tumor cells and precise neutron beam regulation.

[0004] Various types of radiation are generated during radiotherapy, such as low-energy to high-energy neutrons and photons generated during boron neutron capture therapy, which can cause varying degrees of damage to normal tissues. Therefore, in the field of radiotherapy, how to achieve effective treatment while reducing radiation pollution to the external environment, medical personnel, or normal tissues of the irradiated body is a very important issue. Radiotherapy equipment is usually placed in a concrete structure building to isolate the radiation that may be generated by the equipment. In general, the steel bars in the reinforced concrete structure are activated by neutrons to produce long half-life radioactive isotopes, such as cobalt-60 with a half-life of 5.27 years, forming long-decay radioactive waste, which has a negative impact on the environment and radiation safety.

[0005] At the same time, in order to ensure beam quality and improve treatment effect, it is necessary to make the center of the high-energy beam tube coincide with the center of the beam shaping body as much as possible. The engineering tolerance is much higher than the precision requirement of the beam shaping body, and the conventional wooden formwork will also deform during the vibration of the concrete, which will affect the target and beam shaping body cooperation and neutron quality.

[0006] Therefore, it is necessary to provide a new technical solution to solve the above problems. SUMMARY

[0007] In order to solve the above problems, the present application provides a neutron capture therapy system in one aspect, comprising a neutron generating device and a beam shaping body, the neutron generating device comprises an accelerator and a target material, the accelerator accelerates charged particle lines to generate neutrons lines by interacting with the target material, the beam shaping body comprises a reflector, a moderator, a thermal neutron absorber, a radiation shield and a beam exit, the moderator slows down the neutrons generated from the target material to the epithermal neutron energy region, the reflector surrounds the moderator and guides the deviated neutrons back to the moderator to improve the intensity of the epithermal neutron beam, the thermal neutron absorber is used to absorb thermal neutrons to avoid excessive dose to the normal tissue in the shallow layer during treatment, the radiation shield is used to shield the leaked neutrons and photons to reduce the dose of the normal tissue in the non-irradiated area, the neutron capture therapy system further comprises a concrete wall forming a space accommodating the neutron generating device and the beam shaping body, a support module is arranged in the concrete wall, the support module can support the beam shaping body and is used to adjust the position of the beam shaping body, the support module comprises concrete and a reinforcing part at least partially arranged in the concrete. The concrete structure can shield the leaked neutrons and other radiation lines during the operation of the neutron capture therapy system, the reinforcing part can increase the rigidity of the concrete, improve the tensile strength and carrying capacity, and the support structure is modularized, so that the beam shaping body can be adjusted locally, the accuracy requirement is met, the beam quality is improved, and the assembly tolerance of the target is met.

[0008] Further, the neutron capture therapy system further comprises an irradiation room and a charged particle beam generation room, the irradiation room and the charged particle beam generation room are spaces formed by surrounding the concrete wall, the neutron capture therapy system comprises a treatment table arranged in the irradiation room, the irradiated body on the treatment table performs the neutron line irradiation treatment in the irradiation room, and the charged particle beam generation room at least partially accommodates the accelerator, the support module and the beam shaping body are at least partially accommodated in the partition wall of the irradiation room and the charged particle beam generation room.

[0009] Further, the partition wall is provided with an accommodation groove at least partially accommodating the support module on the side close to the irradiation room, and a groove through which a transmission pipe for the accelerator passes on the side close to the charged particle beam generation room, the accommodation groove and the groove penetrate through the partition wall in the neutron line transmission direction, and in the plane perpendicular to the neutron line transmission direction, the cross-sectional profile of the support module is located between the cross-sectional profiles of the accommodation groove and the groove. Thus, the through slit in the beam transmission direction is avoided, the radiation is further reduced, and the support module is adjusted conveniently.

[0010] Further, the support module is provided with an adjusting member, and an adjusting device acts on the adjusting member to adjust the position of the support module and the beam shaping body, thereby improving the coincidence of the center of the beam shaping body and the center of the beam pipeline, and enabling the target to be placed in the center hole of the beam shaping body. A shielding body is filled between the partition wall and the support module to maintain the position of the support module and the beam shaping body, and prevent the rays from passing through the gap between the partition wall and the support module, and the material of the shielding body includes at least one of a photon shielding material and a neutron shielding material, and the shielding body includes at least one of a rigid solid, a flexible solid, a liquid and a powder.

[0011] Further, the partition wall is provided with a shielding plate close to one side of the irradiation chamber, and the shielding plate matches the cross-sectional profile of the support module in a plane perpendicular to the neutron line transmission direction. The shielding plate can shield the neutrons leaked from the gap between the support module and the partition wall, and can also enhance the shielding effect of the partition wall, inhibit the secondary radiation generated by the partition wall, and thereby avoid the radiation to the normal tissues of the patient.

[0012] Another aspect of the present application provides a support module for supporting a beam shaping body for adjusting the beam quality of the rays generated by a radiation generating device, the support module comprising concrete and a reinforcing part at least partially arranged in the concrete, the reinforcing part comprising a formwork and a rib arranged between the formwork, and the formwork and the rib being fixedly connected. The concrete structure can shield the neutrons and other radiation leaked during the operation of the neutron capture therapy system, and the reinforcing part arranged in the concrete can increase the rigidity, improve the tensile strength and increase the carrying capacity; the modular design provides a locally adjustable support for the beam shaping body, so that the beam shaping body meets the accuracy requirement, improves the beam quality and meets the assembly tolerance of the target.

[0013] Further, the elastic modulus of the material of the reinforcing part is not less than 40 GPa, the ultimate strength is not less than 200 MPa, and the yield strength is not less than 100 MPa; more than 90% (wt%) of the material of the reinforcing part is composed of at least one of C, H, O, N, Si, Al, Mg, Li, B, Mn, Cu, Zn, S, Ca, Ti, the half-life of the radioisotope generated after the neutron activation of the reinforcing part is less than 1 year, and the material of the reinforcing part is composed of elements with small neutron interaction cross section or short half-life of the radioisotope generated after the neutron activation, so that the radioactivity derived from the neutron activation is small, and in addition to reasonably inhibiting the dose caused by the secondary radiation, it is also beneficial for the future equipment removal.

[0014] As a kind of preferably, the template includes lower template, left template and right template being arranged in the two sides of the lower template, circular ring template being surrounded by the lower template and left and right template, the muscle includes horizontal transverse muscle, horizontal longitudinal muscle and vertical muscle being distributed in the concrete with predetermined interval in horizontal, vertical and the thickness direction of concrete.

[0015] Further, the horizontal transverse muscle is welded and anchored with the left template, right template and circular ring template, the vertical muscle is welded and anchored with the lower template, circular ring template and horizontal transverse muscle, and the horizontal longitudinal muscle is welded and anchored with the horizontal transverse muscle and vertical muscle.

[0016] Further, the outer wall of the beam shaping body cooperates with the inner surface of the circular ring template, and the beam shaping body is fixedly connected with the support module, so as to constrain the translational freedom and rotational freedom of the beam shaping body. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is the structural schematic diagram of neutron capture therapy system of the embodiment of the application;

[0018] Figure 2 It is the installation schematic diagram of beam shaping body support module of neutron capture therapy system of the embodiment of the application;

[0019] Figure 3 It is the structural schematic diagram of beam shaping body support module of Figure 2

[0020] Figure 4 It is the schematic diagram of A-A section; Figure 3

[0021] Figure 5 It is the schematic diagram of adjusting member of beam shaping body support module of the embodiment of the application;

[0022] Figure 6 It is the schematic diagram of adjusting member in another direction in Figure 5 DETAILED DESCRIPTION

[0023] The embodiment of the application is further described in detail below with reference to the drawings, so that those skilled in the art can implement according to the description and drawings.

[0024] As Figure 1 ​​​The neutron capture therapy system in the embodiment is preferably a boron neutron capture therapy system 100, which includes a neutron generating device 10, a beam shaper 20, a collimator 30, and a treatment table 40. The neutron generating device 10 includes an accelerator 11 and a target material T. The accelerator 11 accelerates charged particles (such as protons, deuterons, etc.) to generate a charged particle beam P (such as a proton beam), and the charged particle beam P irradiates the target material T to generate a neutron beam N. The target material T is preferably a metal target material. Suitable nuclear reactions are selected according to the required neutron yield and energy, the available accelerated charged particle energy and current size, and the physicochemical properties of the metal target material. Commonly discussed nuclear reactions include 7 Li(p,n) 7 Be and 9 Be(p,n) 9 B. Both of these reactions are endothermic reactions. The energy threshold values of the two nuclear reactions are 1.881 MeV and 2.055 MeV, respectively. Since the ideal neutron source for boron neutron capture therapy is a superthermal neutron with a keV energy level, in theory, if protons with an energy slightly higher than the threshold value are used to bombard a lithium metal target, relatively low-energy neutrons can be generated, which can be used in clinical practice without too much moderation. However, the interaction cross section of lithium metal (Li) and beryllium metal (Be) with protons at the threshold energy is not high. In order to generate a large enough neutron flux, protons with higher energy are usually selected to induce nuclear reactions. The ideal target material should have high neutron yield, neutron energy distribution close to the superthermal neutron energy range (which will be described in detail below), low production of strong penetrating radiation, safety, convenience, ease of operation, and high temperature resistance, but in reality, it is difficult to find a nuclear reaction that meets all the requirements. In the embodiment of the present application, a target material made of lithium metal is used. However, as is well known to those skilled in the art, the target material T can also be made of metal materials other than lithium and beryllium, such as tantalum (Ta) or tungsten (W); the target material T can be in the form of a circular plate, other solid shapes, or a liquid substance (liquid metal). The accelerator 11 can be a linear accelerator, a cyclotron, a synchrotron, or a synchrocyclotron. The neutron generating device 10 can also be a nuclear reactor without using an accelerator and a target material. Regardless of whether the neutron source for boron neutron capture therapy comes from a nuclear reactor or a nuclear reaction between an accelerator charged particle and a target material, the actual generated radiation field is a mixed radiation field, i.e., the beam contains neutrons, photons, and other radiation lines with low to high energy. For boron neutron capture therapy of deep tumors, the more the content of the remaining radiation lines other than superthermal neutrons, the greater the proportion of non-selective dose deposition in normal tissues, so these unnecessary dose radiation should be minimized. In addition, for the normal tissues of the irradiated body, various radiation lines should also be avoided to minimize unnecessary dose deposition.

[0025] The neutron beam N generated by the neutron generating device 10 irradiates the irradiated body 200 on the treatment table 40 in turn through the beam shaping body 20 and the collimator 30. The beam shaping body 20 can adjust the beam quality of the neutron beam N generated by the neutron generating device 10, and the collimator 30 is used to converge the neutron beam N so that the neutron beam N has higher targeting in the process of treatment. By adjusting the collimator 30, the direction of the beam and the positional relationship between the beam and the irradiated body 200 on the treatment table 40 can be adjusted. The position of the treatment table 40 and the irradiated body 200 can also be adjusted so that the beam is aligned with the tumor cells M in the irradiated body 200. These adjustments can be manually operated by a person or automatically implemented through a series of control mechanisms. It can be understood that the present application can also not have a collimator, and the beam directly irradiates the irradiated body 200 on the treatment table 40 after coming out of the beam shaping body 20.

[0026] The beam shaping body 20 further comprises a reflector 21, a moderator 22, a thermal neutron absorber 23, a radiation shield 24 and a beam exit 25. The neutrons generated by the neutron generating device 10 have a wide energy spectrum. In addition to the epithermal neutrons that meet the treatment requirements, other types of neutrons and photons need to be reduced as much as possible to avoid harm to the operators or the irradiated body. Therefore, the neutrons from the neutron generating device 10 need to pass through the moderator 22 to adjust the fast neutron energy (> 40 keV) in the moderator 22 to the epithermal neutron energy range (0.5 eV-40 keV) and reduce the thermal neutrons (<0.5 eV) as much as possible. The moderator 22 is made of a material with a large fast neutron interaction cross section and a small epithermal neutron interaction cross section. As a preferred embodiment, the moderator 13 is made of at least one of D2O, AlF3, Fluental, CaF2, Li2CO3, MgF2 and Al2O3. The reflector 21 surrounds the moderator 22 and reflects the neutrons diffused to the four directions through the moderator 22 back to the neutron beam N to improve the utilization rate of the neutrons. The reflector 21 is made of a material with strong neutron reflection ability. As a preferred embodiment, the reflector 21 is made of at least one of Pb or Ni. The moderator 22 has a thermal neutron absorber 23 at the rear part. The thermal neutron absorber 23 is made of a material with a large thermal neutron interaction cross section. As a preferred embodiment, the thermal neutron absorber 23 is made of Li-6. The thermal neutron absorber 23 is used to absorb the thermal neutrons passing through the moderator 22 to reduce the content of thermal neutrons in the neutron beam N and avoid causing excessive dose to the shallow normal tissue during treatment. The radiation shield 24 is used to shield the neutrons and photons that leak from the part other than the beam exit 25. The material of the radiation shield 24 includes at least one of a photon shielding material and a neutron shielding material. As a preferred embodiment, the material of the radiation shield 24 includes the photon shielding material Pb and the neutron shielding material PE. The collimator 30 is arranged at the rear part of the beam exit 25. The epithermal neutron beam from the collimator 30 irradiates the irradiated body 200. After passing through the shallow normal tissue, the epithermal neutron beam is moderated to thermal neutrons to reach the tumor cells M. It can be understood that the beam shaping body 20 can also have other configurations as long as the epithermal neutron beam required for treatment can be obtained.

[0027] After the irradiated body 200 takes or injects the boron (B-10) containing drug, the boron containing drug selectively accumulates in the tumor cells M. Then, by using the characteristics that the boron (B-10) containing drug has a high capture cross section for thermal neutrons, the thermal neutron beam is converted into alpha particles and lithium nuclei by the following reaction: 10 B(n, α) 7 Li neutron capture and nuclear fission reaction produces 4 He and 7Li two heavy charged particles. The average energy of two charged particles is about 2.33 MeV, with high linear energy transfer (LET), short range characteristics, the linear energy transfer and range of alpha short particles are 150 keV / μm, 8 μm, respectively, while 7 Li heavy particles are 175 keV / μm, 5 μm, the total range of two particles is about equivalent to a cell size, so the radiation damage caused to the organism can be limited to the cell level, so as to achieve the purpose of killing tumor cells locally without causing too much damage to normal tissues.

[0028] In this embodiment, a radiation shielding device 50 is further provided between the irradiated body 200 and the beam exit 25, which shields the radiation of the beam from the beam exit 25 to the normal tissues of the irradiated body. It can be understood that the radiation shielding device 50 can also not be provided.

[0029] The boron neutron capture therapy system 100 is entirely contained in a building constructed of concrete. Specifically, the boron neutron capture therapy system 100 further includes an irradiation room 101 and a charged particle beam generating room 102. The irradiated body 200 on the treatment table 40 is subjected to neutron beam N irradiation treatment in the irradiation room 101. The charged particle beam generating room 102 at least partially contains the accelerator 11. The beam shaping body 20 is at least partially contained in the partition wall 103 between the irradiation room 101 and the charged particle beam generating room 102. It can be understood that the partition wall 103 can completely separate the irradiation room 101 and the charged particle beam generating room 102; or it can be a partial partition between the irradiation room 101 and the charged particle beam generating room 102, and the irradiation room 101 and the charged particle beam generating room 102 are communicated. The target material T can be one or more, and the charged particle beam P can selectively act on one or more target materials T or simultaneously act on multiple target materials T to generate one or more therapeutic neutron beams N. Corresponding to the number of target materials T, the beam shaping body 20, the collimator 30, and the treatment table 40 can also be one or more; multiple treatment tables can be provided in the same irradiation room, or a separate irradiation room can be provided for each treatment table.

[0030] The irradiation room 101 and the charged particle beam generating room 102 are surrounded by a space formed by a concrete wall W (including the partition wall 103). The concrete structure can shield the leaked neutrons and other radiation lines during the operation of the boron neutron capture therapy system 100. In combination with the shielding effect of the shielding device 50, the leakage of the neutron beam N and other radiation lines can be effectively prevented. Figure 2The beam shaping body 20 is supported by a support module 60 arranged in the partition wall 103. An accommodating groove 1031 for at least partially accommodating the support module 60 is arranged on the side of the partition wall 103 close to the irradiation chamber 102, and a groove 1032 for the transmission tube of the accelerator to pass through is arranged on the side close to the charged particle beam generating chamber 101, so that the accommodating groove 1031 and the groove 1032 pass through the partition wall in the neutron beam N transmission direction. In this embodiment, the wall surface of the partition wall 103 is a plane, and the neutron beam N transmission direction is perpendicular to the wall surface of the partition wall 103. The support structure is modularized, so that the beam shaping body can be adjusted locally, meet the accuracy requirement, improve the beam quality, and meet the assembly tolerance of the target. In the plane perpendicular to the neutron beam N transmission direction, the cross-sectional profile of the support module 60 is located between the cross-sectional profiles of the accommodating groove 1031 and the groove 1032, so as to avoid the appearance of a through gap in the beam transmission direction, further reduce radiation, and facilitate adjustment of the support module 60. In this embodiment, the support module 60 is a cuboid as a whole, and the accommodating groove 1031 and the groove 1032 are both "L" shaped in the cross section perpendicular to the neutron beam N transmission direction. The side walls of the accommodating groove 1031 and the groove 1032 are parallel to the neutron beam N transmission direction. The partition wall 103 further comprises a shielding plate 70 arranged on the side close to the irradiation chamber 102. The shielding plate 70 can enhance the shielding effect of the partition wall, suppress the secondary radiation generated by the partition wall, and thus avoid radiation to the normal tissue of the patient. In the plane perpendicular to the neutron beam N transmission direction, the shielding plate 70 can match the cross-sectional profile of the support module 60, so as to shield the neutrons leaked from between the support module and the partition wall. The shielding plate is a PE plate. It can be understood that the side of the partition wall 103 close to the charged particle beam generating chamber 102 and the side of the support module 60 close to the irradiation chamber 101 can also be provided with a shielding plate. The shielding plate can be made of lead or other neutron or photon shielding materials, and can also not be provided with a shielding plate.

[0031] In combination Figures 3-4The support module 60 comprises concrete and a reinforcing part 61 (to be described below) arranged at least partially in the concrete. Since the tensile strength of concrete is low and it is easy to crack, and the beam shaping body is very sensitive to deformation, the support structure is required to have sufficient rigidity, and therefore the reinforcing part arranged in the concrete can increase the rigidity, improve the tensile strength, and enhance the carrying capacity. The elastic modulus of the material of the reinforcing part is not less than 40 GPa, the ultimate strength is not less than 200 MPa, and the yield strength is not less than 100 MPa. Since neutrons are generated in the beam shaping body, the material at the periphery is most seriously activated. The material of the reinforcing part is composed of elements with a small cross section for interaction with neutrons or a short half-life (less than 1 year) of a radioisotope generated after activation by neutrons, for example, more than 90% (weight percentage) of the material of the reinforcing part is composed of at least one of C, H, O, N, Si, Al, Mg, Li, B, Mn, Cu, Zn, S, Ca, and Ti. In this embodiment, the material of the reinforcing part is at least partially an aluminum alloy. The half-life of aluminum activated by neutrons is relatively short, only 2.2 minutes. In traditional reinforced concrete structures, elements such as iron, cobalt, and nickel in the reinforcing steel are activated by neutrons and have a long half-life, for example, the half-life of cobalt 60 is 5.27 years. The use of aluminum alloy greatly reduces the radioactivity derived from neutron activation within a limited time, which is more conducive to the future removal of equipment, in addition to reasonably inhibiting the dose caused by secondary radiation. The material of the reinforcing part can further be an aluminum-magnesium alloy, or a carbon fiber composite material, a glass fiber composite material, or a combination thereof.

[0032] The reinforcing part 61 comprises a formwork 611 and a rib 612 arranged between the formworks, and the formwork 611 is fixedly connected to the rib 612. The formwork 611 comprises a lower formwork 6111, left and right formworks 6112 and 6113 arranged on both sides of the lower formwork 6111, and a circular ring formwork 6114 surrounded by the lower formwork and the left and right formworks. The formwork 611 is made of an aluminum alloy and serves as an anchor plate for the rib 612. In this embodiment, the beam shaping body 20 is in the shape of a cylinder, and it can be understood that when the beam shaping body is configured in other shapes, the circular ring formwork can be replaced by other shaped formworks accordingly. The rib 612 comprises horizontal cross ribs 6121, horizontal longitudinal ribs 6122, and vertical ribs 6123, which are distributed at a predetermined interval in the concrete between the circular ring formwork and the left and right formworks, the lower formwork, and the horizontal, vertical, and thickness directions of the concrete. The interval is determined according to specific conditions and is only schematically shown in the figure. The rib is also made of an aluminum alloy. In this embodiment, the horizontal cross ribs 6121 are welded and anchored to the left and right formworks 6112 and 6113 and the circular ring formwork 6114, the vertical ribs 6123 are welded and anchored to the lower formwork 6111, the circular ring formwork 6114, and the horizontal cross ribs 6121, and the horizontal longitudinal ribs 6122 are welded and anchored to the horizontal cross ribs 6121 and the vertical ribs 6123. It can be understood that the formwork and the rib can also have other arrangement modes, and the welding sequence and process can be performed according to other modes familiar to those skilled in the art, or other fixing modes can be used.

[0033] During construction, front and rear formworks (not shown in the figure) are also needed to support the front and rear sides and the upper side of the support module 60, which do not require anchoring, so traditional wooden formworks are used. The concrete is poured into the accommodating cavity formed between the lower formwork 6111, the left formwork 6112, the right formwork 6113, the circular ring formwork 6114 and the front and rear formworks. The upper side is not provided with a formwork, which is convenient for observing the state of the concrete during construction. After the concrete is poured full, the upper side is scraped flat with a board. After the concrete is poured and cured, the front and rear formworks are removed to form the support module 60, which is then transported to the partition wall 103 and installed in the accommodating groove 1031. Then, the beam shaping body 20 is placed in the support module 60, and the outer wall of the beam shaping body 20 is matched with the inner surface of the circular ring formwork 6114. In order to constrain the translational and rotational degrees of freedom of the beam shaping body 20, the beam shaping body 20 is fixedly connected with the support module 60, such as setting threaded holes on the circular ring formwork 6114 and holes on the corresponding position of the outer wall of the beam shaping body 20, and connecting the beam shaping body 20 and the circular ring formwork 6114 with bolts. It can be understood that other connection methods can also be used. Before pouring the concrete, the threaded holes of the circular ring formwork 6114 are stuffed with plastic protective sleeves to prevent the concrete from leaking out of the threaded holes and to protect the threads. In order to ensure the compactness of the concrete below the circular ring formwork, an opening can be made below the front or rear formwork, and the concrete is poured from the opening. After the concrete is poured and cured, the plastic protective sleeves stuffed in the threaded holes of the circular ring formwork 6114 are removed, the beam shaping body is placed in the accommodating cavity formed on the inner surface of the circular ring formwork 6114, and then the beam shaping body 20 and the support module 60 are connected with bolts. It can be understood that the construction process can also be carried out in other ways known to those skilled in the art.

[0034] Then the positions of the support module 60 and the beam shaping body 20 are adjusted, combined with the Figures 5-6An adjusting member 62 is arranged on the support module 60. A jack or other adjusting device (not shown) acts on the adjusting member 62 to adjust the position of the support module 60 and the beam shaping body 20, so that the beam shaping body 20 moves between a first position and a second position. In the first position, the central axis of the beam shaping body 20 is substantially coincident with the central axis of the transmission tube of the accelerator. In the second position, the central axis of the beam shaping body 20 is not coincident with the central axis of the transmission tube of the accelerator. Thus, the coincidence of the central axis of the beam shaping body and the central axis of the beam pipeline is improved, and the target can be placed in the central hole of the beam shaping body. The adjusting member 62 is arranged at the lower part of the side wall of the support module 60 facing the irradiation chamber 101. It can be understood that the adjusting member can also be arranged at other positions. The adjusting member can also be arranged on the beam shaping body, and the beam shaping body is directly driven by the adjusting member to adjust the position. Since the jack acts on the adjusting member in the form of concentrated force, a torsion bar can be arranged at the corresponding position of the reinforcing part 61 to increase the strength. In the embodiment, the adjusting member 62 is an L-shaped bracket having a first side plate 621 and a second side plate 622 perpendicular to each other. The first side plate 621 is fixed to the lower part of the side wall of the support module 60 facing the irradiation chamber 101 by bolts or the like. The jack acts on the second side plate 622. The adjusting member 62 further includes a reinforcing rib plate 623 connecting the first and second side plates to increase the strength. The bracket is made of steel plate. It can be understood that other structures or other materials can also be used.

[0035] After adjustment, the support module 60 is fixed (for example, a steel plate is arranged in the gap between the support module and the floor, and the support module is fixed to the floor by bolts or the like), and a shielding body (not shown) is filled between the partition wall 103 and the support module 60 to maintain the position of the support module and the beam shaping body and prevent the rays from passing through the gap between the partition wall and the support module. The material of the shielding body includes at least one of a photon shielding material and a neutron shielding material, which can be a rigid solid cut to a suitable size, such as lead, lead-antimony alloy, Teflon, graphite, paraffin, PE, PE containing boron carbide or lithium carbonate or lithium fluoride, PMMA (acrylic), PMMA containing boron carbide or lithium carbonate or lithium fluoride; or a powder filled in a rigid container or a flexible container cut to a suitable size, such as boron carbide or lithium carbonate or lithium fluoride powder; or a liquid filled in a rigid container or a flexible container cut to a suitable size, such as water, heavy water, boric acid dissolving boron carbide or lithium carbonate or lithium fluoride powder; or a flexible solid, such as rubber or silicone. The adjusting member 62 can be removed, and then the shielding plate 70 is installed to shield the shielding body, further reducing radiation.

[0036] The boron neutron capture therapy system 100 can further include a preparation room, a control room and other spaces for assisting treatment, and each irradiation room can be configured with a preparation room for preparing the irradiated object to the treatment table, injecting boron medicine, simulating treatment planning and other preparations before irradiation treatment. A connecting passage is provided between the preparation room and the irradiation room, and after the preparation work is completed, the irradiated object is directly pushed into the irradiation room or automatically enters the irradiation room by the control mechanism through the track. The control room is used to control the accelerator, the beam transmission part, the treatment table and the like, and controls and manages the whole irradiation process. The management personnel in the control room can also monitor multiple irradiation rooms at the same time.

[0037] The concrete wall in the embodiment is a boron-containing barite concrete wall with a thickness of 1 m or more and a density of 3 g / c.c. The boron-containing concrete has better neutron absorption performance, which not only enhances the radiation shielding effect of the concrete, but also reduces the neutron exposure of the metal materials in the concrete. It can be understood that it can also have other thicknesses or densities or be replaced by other materials, and the thickness, density or material of the concrete walls of different parts can also be different. It can be understood that the present application can also be applied to other types of neutron irradiation systems; it can also be applied to other radiation irradiation systems, at this time the neutron generating device can be replaced by other radiation generating devices, and the materials of the concrete and the support module can be replaced as needed.

[0038] Although the above describes the specific embodiments of the present application in order to facilitate the understanding of the present application by those skilled in the art, it should be clear that the present application is not limited to the scope of the specific embodiments, and for those skilled in the art, as long as various changes are within the spirit and scope of the present application defined and determined by the appended claims, these changes are obvious and within the scope of the present application claimed.

Claims

1. A neutron capture therapy system, characterized in that, The system includes a neutron generating device and a beam shaper. The neutron generating device includes an accelerator and a target. The charged particle lines generated by the accelerator interact with the target to generate neutron lines. The beam shaper includes a reflector, a decelerator, a thermal neutron absorber, a radiation shield, and a beam exit. The decelerator slows down neutrons generated from the target to the hyperthermal neutron energy region. The reflector surrounds the decelerator and guides deviated neutrons back to the decelerator to increase the intensity of the hyperthermal neutron beam. The thermal neutron absorber absorbs thermal neutrons to avoid excessive dose to superficial normal tissues during treatment. The radiation shield shields leaked neutrons and photons to reduce the dose to normal tissues in non-irradiated areas. The neutron capture therapy system also includes a concrete wall forming a space to accommodate the neutron generating device and the beam shaper. A support module is disposed within the concrete wall. The support module supports the beam shaper and is used to adjust its position. The support module includes concrete and a reinforcement portion at least partially disposed within the concrete.

2. The neutron capture therapy system as described in claim 1, characterized in that, The neutron capture therapy system further includes an irradiation chamber and a charged particle beam generation chamber, which are spaces enclosed by the concrete wall. The neutron capture therapy system includes a treatment table disposed in the irradiation chamber, on which the irradiated body undergoes neutron beam irradiation therapy. The charged particle beam generation chamber at least partially houses the accelerator, and the support module and beam shaper are at least partially housed within the partition wall between the irradiation chamber and the charged particle beam generation chamber.

3. The neutron capture therapy system as described in claim 2, characterized in that, The partition wall has a receiving groove that at least partially accommodates the support module on the side near the irradiation chamber, and a groove for the transmission tube of the accelerator to pass through on the side near the charged particle beam generation chamber. The receiving groove and the groove penetrate the partition wall in the neutron line transmission direction. On a plane perpendicular to the neutron line transmission direction, the cross-sectional profile of the support module is located between the cross-sectional profiles of the receiving groove and the groove.

4. The neutron capture therapy system as described in claim 2, characterized in that, The support module is provided with an adjustment component, and the position of the support module and the beam shaper is adjusted by the adjustment device acting on the adjustment component. The space between the partition wall and the support module is filled with a shield to maintain the position of the support module and the beam shaper. The material of the shield includes at least one of photon shielding material and neutron shielding material, and the shield includes at least one of rigid solid, flexible solid, liquid and powder.

5. The neutron capture therapy system as described in claim 2, characterized in that, A shielding plate is provided on the side of the partition wall near the irradiation chamber. On a plane perpendicular to the neutron line transmission direction, the shielding plate matches the cross-sectional profile of the support module.

6. A support module for supporting a beam shaper, the beam shaper being used to adjust the beam quality of radiation generated by a radiation generating device, characterized in that, The support module is disposed within a concrete wall, which forms a space to accommodate the beam shaper. A receiving groove is provided on one side of the concrete wall, which at least partially accommodates the support module. The support module includes concrete and a reinforcing part disposed at least partially within the concrete. The reinforcing part includes a template and ribs disposed between the templates. The template and ribs are fixedly connected. The beam shaper is accommodated within the receiving cavity formed by the support module.

7. The support module for supporting the beam shaper as described in claim 6, characterized in that, The material of the reinforcing part has an elastic modulus of not less than 40 GPa, an ultimate strength of not less than 200 MPa, and a yield strength of not less than 100 MPa. More than 90% (by weight) of the material of the reinforcing part is composed of at least one element selected from C, H, O, N, Si, Al, Mg, Li, B, Mn, Cu, Zn, S, Ca, and Ti. The half-life of the radioactive isotope generated after the reinforcing part is activated by neutrons is less than 1 year.

8. The support module for supporting the beam shaper as described in claim 6, characterized in that, The template includes a lower template, a left template and a right template disposed on both sides of the lower template, and a circular template surrounded by the lower template and the left and right templates. The reinforcement includes horizontal horizontal bars, horizontal longitudinal bars and vertical bars distributed in the concrete at predetermined intervals in the horizontal, vertical and thickness directions of the concrete.

9. The support module for supporting a beam shaper as described in claim 8, characterized in that, The horizontal reinforcing bars are welded and anchored to the left template, right template, and circular template; the vertical reinforcing bars are welded and anchored to the lower template, circular template, and horizontal reinforcing bars; and the horizontal longitudinal reinforcing bars are welded and anchored to the horizontal reinforcing bars and vertical reinforcing bars.

10. The support module for supporting a beam shaper as described in claim 8, characterized in that, The outer wall of the beam shaper mates with the inner surface of the annular template, and the beam shaper is fixedly connected to the support module.

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