WO2020211581A1 - Système de thérapie par capture de neutrons - Google Patents

Système de thérapie par capture de neutrons Download PDF

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Publication number
WO2020211581A1
WO2020211581A1 PCT/CN2020/079653 CN2020079653W WO2020211581A1 WO 2020211581 A1 WO2020211581 A1 WO 2020211581A1 CN 2020079653 W CN2020079653 W CN 2020079653W WO 2020211581 A1 WO2020211581 A1 WO 2020211581A1
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WIPO (PCT)
Prior art keywords
neutron
wall
supplementary
reflector
unit
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PCT/CN2020/079653
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English (en)
Chinese (zh)
Inventor
陈韦霖
江涛
闫发智
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中硼(厦门)医疗器械有限公司
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Priority claimed from CN201910308298.5A external-priority patent/CN111821581A/zh
Priority claimed from CN201910623203.9A external-priority patent/CN111821584A/zh
Application filed by 中硼(厦门)医疗器械有限公司 filed Critical 中硼(厦门)医疗器械有限公司
Priority to EP20791113.2A priority Critical patent/EP3957362A4/fr
Priority to JP2021559125A priority patent/JP7312850B2/ja
Priority to AU2020260204A priority patent/AU2020260204B2/en
Priority to CA3135517A priority patent/CA3135517C/fr
Publication of WO2020211581A1 publication Critical patent/WO2020211581A1/fr
Priority to US17/494,874 priority patent/US12011615B2/en
Priority to JP2023112730A priority patent/JP2023123865A/ja
Priority to AU2023270215A priority patent/AU2023270215A1/en

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N5/00—Radiation therapy
    • A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
    • G21K1/02—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diaphragms, collimators

Definitions

  • the invention relates to a radiation irradiation system, in particular to a neutron capture treatment system.
  • radiotherapy such as cobalt sixty, linear accelerator, and electron beam has become one of the main methods of cancer treatment.
  • traditional photon or electron therapy is limited by the physical conditions of radiation itself. While killing tumor cells, it will also cause damage to a large number of normal tissues along the beam path.
  • traditional radiotherapy For the more radiation-resistant malignant tumors (such as: glioblastoma multiforme, melanoma), the treatment effect is often poor.
  • neutron capture therapy is a combination of the above two concepts, such as boron neutron capture therapy, through the specific accumulation of boron-containing drugs in tumor cells, combined with precise neutron beam regulation, to provide better than traditional radiation Cancer treatment options.
  • BNCT Boron Neutron Capture Therapy
  • 10 B boron-containing drugs
  • 10 B (n, ⁇ ) 7 Li neutron capture and nuclear fission reaction Two heavily charged particles, 4 He and 7 Li, are produced. 1 and 2, which respectively show the schematic diagram of the boron neutron capture reaction and the 10 B(n, ⁇ ) 7 Li neutron capture nuclear reaction equation.
  • the average energy of the two charged particles is about 2.33 MeV, which has high linearity Transfer (Linear Energy Transfer, LET), short-range characteristics, the linear energy transfer and range of alpha particles are 150keV/ ⁇ m, 8 ⁇ m, and 7 Li heavy-load particles are 175keV/ ⁇ m, 5 ⁇ m, the total range of the two particles is approximately equivalent to The size of a cell, so the radiation damage caused to organisms can be limited to the cell level.
  • boron-containing drugs are selectively aggregated in tumor cells, with an appropriate neutron source, they can not cause too much damage to normal tissues. Under the premise, the purpose of locally killing tumor cells is achieved.
  • boron neutron capture therapy depends on the concentration of boron-containing drugs and the number of thermal neutrons at the tumor cell location, it is also called binary cancer therapy. It can be seen that, in addition to the development of boron-containing drugs, The improvement of neutron source flux and quality plays an important role in the research of boron neutron capture therapy.
  • a neutron capture treatment system including a neutron generation device and a beam shaping body
  • the neutron generation device includes an accelerator and a target, so The charged particle beam accelerated by the accelerator interacts with the target to generate neutrons, the neutrons form a neutron beam, the neutron beam defines a main axis
  • the beam shaping body includes a support part and a filling
  • the main body part in the support part includes a retarder, a reflector, and a radiation shield, and the retarder decelerates the neutrons generated from the target to the superthermal neutron energy zone.
  • the body surrounds the retarder body and guides the neutrons that deviate from the main axis back to the main axis to increase the intensity of the superthermal neutron beam.
  • the radiation shield is used to shield the leaking neutrons and photons to reduce non-irradiation The normal tissue dose of the area.
  • the supporting portion includes an outer wall circumferentially closed around the main shaft, the outer wall surrounds and forms a receiving portion, the main body portion is disposed in the receiving portion, and the receiving portion includes at least one receiving unit.
  • the accommodating unit accommodates at least one of the retarder, reflector and radiation shield.
  • the supporting portion further includes first and second side plates respectively provided on both sides of the outer wall along the direction of the neutron beam and connected with the outer wall, and are provided on each side along the direction of the neutron beam.
  • At least one horizontal plate between the first and second side plates is circumferentially closed around the main axis and extends between the first and second side plates or between the horizontal plate and the first/second side plates.
  • the first side plate is provided with a hole through which the transmission tube of the accelerator passes
  • the second side plate is provided with a hole forming a beam exit, so
  • a plurality of accommodating units are formed between the outer wall, the inner wall, the horizontal plate and the first and second side plates.
  • the radiation shielding body includes a neutron shielding body and a photon shielding body. At least one of the accommodating units simultaneously accommodates the retarder Body/neutron shield and reflector.
  • the inner wall includes a first and a second inner wall
  • the horizontal plate includes a first horizontal plate
  • the first inner wall extends between the first side plate and the first horizontal plate.
  • the second inner wall extends from the first horizontal plate along the neutron beam direction and is used to accommodate at least a part of the retarder.
  • the retarder body includes a basic part and a supplementary part
  • the accommodating unit includes a first accommodating unit and a second accommodating unit adjacent to each other, the basic part is accommodated in the first accommodating unit, and the basic part
  • a central hole is provided at the end facing the first side plate, the central hole is used to accommodate the transmission tube and the target, and at least a part of the supplementary part and the reflector is accommodated in the second accommodating unit
  • the first accommodating unit is surrounded by the second inner wall, and the radial distance from the first inner wall to the main shaft is smaller than the radial distance from the second inner wall to the main shaft.
  • the basic part of the retarder surrounds the target, so that the neutrons generated by the target can be effectively retarded in all directions, which can further improve the neutron flux and beam quality.
  • the material of the basic part is magnesium fluoride containing Li-6
  • the basic part also serves as a thermal neutron absorber
  • the supplementary part includes a first supplementary unit and a second supplementary unit.
  • the material of the unit is aluminum alloy
  • the material of the second supplementary unit is Teflon
  • the material of the reflector is lead
  • the reflector also serves as a photon shield
  • the first and second supplementary units are integrally arranged
  • the reflector in the second accommodating unit is divided into two cone shapes adjacent to each other in opposite directions, and the first and second supplementary units are arranged in sequence along the neutron beam direction, The interface of the first and second supplementary units is perpendicular to the direction of the neutron beam.
  • the aluminum alloy block and the Teflon block are respectively used as the first and second supplementary units of the retarder, which can reduce the manufacturing cost of the retarder, and at the same time, it will not have a large impact on the beam quality.
  • the first and second The supplementary unit is arranged as two cones adjacent to each other in opposite directions, which can obtain better beam quality and treatment effect. Teflon also has a better fast neutron absorption effect, which can reduce the fast neutron content in the beam.
  • a lead plate shielding plate is also arranged between the magnesium fluoride block in the first containing unit and the positioning ring/stop ring, and the basic part and the shielding plate are arranged in sequence along the neutron beam direction,
  • the positioning ring and the stop ring are made of a material with a short inherent half-life of the activated nucleus produced by the activation reaction, the material of the shielding plate is lead, and the lead plate shielding plate is in the direction of the neutron beam
  • the thickness is less than or equal to 5cm, it will not reflect neutrons passing through the retarder, and lead can absorb the gamma rays released from the retarder.
  • the outer wall, at least one inner wall, and at least one horizontal plate integrally form a main frame, and the material of the main frame, the first and second side plates is activated by neutrons, and the half-life of radioisotopes generated by neutrons is less than 7 days, so
  • the main frame, the first and second side plates are made of aluminum alloy, titanium alloy, lead-antimony alloy, cast aluminum, cobalt-free steel, carbon fiber, PEEK or high molecular polymer.
  • the material of the main frame is selected from aluminum alloy, it has good mechanical properties and the radioisotope produced by neutron activation has a short half-life; when the material of the first and second side plates is selected lead-antimony alloy, lead can play To further shield the role of radiation, at the same time the lead-antimony alloy has a higher strength.
  • the accommodating unit includes a third accommodating unit, at least a part of the neutron shielding body and at least a part of the reflector are accommodated in the third accommodating unit, and the neutron shielding body
  • the material is PE
  • the material of the reflector is lead
  • the reflector also serves as a photon shield
  • the reflector and the neutron shield in the third accommodating unit are arranged in sequence along the neutron beam direction
  • the interface between the reflector and the neutron shield in the third accommodating unit is perpendicular to the neutron beam direction.
  • the supporting portion further includes a radial partition that divides the accommodating unit into several sub-regions in the circumferential direction, and the radial partition is arranged between the first and second side plates or Between the horizontal plate and the first/second side plate or between the horizontal plate and the horizontal plate, and extend from the outer wall to the inner wall or between two inner walls.
  • a beam shaping body for a neutron capture treatment system the neutron capture treatment system includes a neutron generating device, and the neutrons generated by the neutron generating device form a neutron beam
  • the beam shaping body can adjust the beam quality of the neutron beam
  • the beam shaping body includes a support part and a main body part filled in the support part, the support part forms at least one accommodating unit, each The accommodating unit accommodates at least a part of the main body part.
  • a third aspect of the present invention provides a beam shaping body for a neutron capture therapy system
  • the neutron capture therapy system includes a neutron generation device
  • the neutron generation device includes an accelerator and a target
  • the accelerator The accelerated charged particle beam interacts with the target to generate the neutron
  • the neutron forms a neutron beam
  • the neutron beam defines a main axis
  • the beam shaping body includes a retarder and a reflector And a radiation shield
  • the retarder decelerates the neutrons generated by the neutron generator to the superthermal neutron energy zone
  • the reflector surrounds the retarder and deflects the neutrons that deviate from the main axis.
  • the radiation shield is used to shield the leaking neutrons and photons to reduce the normal tissue dose in the non-irradiated area
  • the retarder includes a basic part and a surrounding area.
  • the supplementary part of the basic part, the beam shaping body further includes a support part for supporting the beam shaping body, the support part includes a wall surrounding the main axis, and the basic part and the supplementary part have different materials And separated by the wall.
  • the support part can prevent the deformation and damage of the main material of the beam shaping body, which will affect the target replacement and beam quality;
  • the supplementary part is made of easily available materials, which can reduce the manufacturing cost of the retarder and has a certain neutron retarding effect. , Will not have a big impact on the beam quality.
  • the wall includes a first wall and a second wall which are arranged in sequence along the direction of the neutron beam and are circumferentially closed around the direction of the neutron beam, and a second wall connecting the first wall and the second wall.
  • a horizontal plate the horizontal plate extends perpendicular to the direction of the neutron beam, the first wall is used to install the transmission tube of the accelerator, and the second wall forms a receiving cavity for the basic part of the retarder;
  • the material of the basic part includes at least one of D 2 O, Al, AlF 3 , MgF 2 , CaF 2 , LiF, Li 2 CO 3 or Al 2 O 3 , which has a large cross-section of interaction with fast neutrons and is superheated. The sub-action cross-section is small and has a good retarding effect; the basic part contains Li-6, and the basic part also serves as the thermal neutron absorber.
  • the basic part includes first and second end faces that are substantially perpendicular to the direction of the neutron beam, the first and second end faces are arranged in sequence along the direction of the neutron beam, and the first end face is provided with a center
  • the central hole is used to accommodate the transfer tube and the target, the radial distance from the first wall to the main shaft is smaller than the radial distance from the second wall to the main shaft, and the basic Partially surrounds the target material, so that the neutrons generated by the target material can be effectively slowed down in all directions, which can further improve the neutron flux and beam quality.
  • a shielding plate is arranged adjacent to the second end surface.
  • the shielding plate is a lead plate. Lead can absorb gamma rays released from the retarder.
  • the thickness of the shielding plate in the neutron beam direction is less than or equal to 5 cm. Will reflect neutrons passing through the slow body.
  • the supporting part further includes a radial partition that divides the supplementary part into at least two sub-modules in the circumferential direction around the main shaft, and the plane on which the radial partition is located extends through For the main shaft, the at least two sub-modules are separated by the radial partition.
  • the supplementary part includes adjoining first and second supplementary units, the materials of the basic part, the first and second supplementary units are all different, the basic part is columnar, and the first The whole arrangement with the second supplementary unit includes at least one cone shape, which can obtain better beam quality and treatment effect.
  • the material of the first supplementary unit includes at least one of Zn, Mg, Al, Pb, Ti, La, Zr, Bi, Si, and C
  • the material of the second supplementary unit is Teflon or graphite.
  • the first and second supplementary units are arranged in sequence along the direction of the neutron beam, and the first and second supplementary units are arranged as two cones adjacent to each other in opposite directions as a whole.
  • the first supplementary part of the retarder is made of easily available materials, which can reduce the manufacturing cost of the retarder, and has a certain neutron retarding effect, which will not have a greater impact on the beam quality; the second supplementary part is selected
  • the material with better fast neutron absorption effect than the first supplement part can reduce the fast neutron content in the beam.
  • the first supplementary unit is arranged in the shape of two cones adjacent to each other in opposite directions, and the first supplementary unit includes a first cone portion and a second cone portion sequentially arranged along the neutron beam direction ,
  • the radial dimension of the outer contour of the first cone portion gradually increases along the overall trend of the neutron beam direction
  • the radial dimension of the second cone portion on the outer contour of the first cone portion is the largest Is connected to the first cone portion
  • the radial size of the outer contour of the second cone portion gradually decreases along the overall trend of the neutron beam direction
  • the second supplementary unit is located in the second cone
  • the smallest radial dimension of the outer contour of the part is adjacent to the second cone part, and the radial dimension of the outer contour of the second supplementary unit gradually decreases along the overall trend of the neutron beam direction.
  • the cross-sectional contours of the first and second supplementary units along the plane where the main axis is located are irregular quadrilaterals or polygons, and the first supplementary unit has the same shape as that of the first cone.
  • the first side in contact with the reflector, the second side in contact with the reflector in the second cone portion, and the third side in contact with the second supplementary unit, in the first and second cones The body part has a fourth side in contact with the wall
  • the second supplementary unit has a fifth side in contact with the first supplementary unit, a sixth side in contact with the reflector, and is in contact with the wall
  • the third side and the fifth side adjoin and serve as the interface of the first and second supplementary units, and the interface is perpendicular to the direction of the neutron beam.
  • the fourth aspect of the present invention provides a beam shaping body for a neutron capture therapy system
  • the neutron capture therapy system includes a neutron generating device, and the neutrons generated by the neutron generating device form a neutron beam
  • the neutron beam defines a main axis
  • the beam shaping body can adjust the beam quality of the neutron beam
  • the beam shaping body includes a support part and a main body part filled in the support part.
  • the supporting part includes a supporting frame, the supporting frame is forged by the forging equipment to form a cylinder from the blank after being heated by the heating device, and the cylinder is processed and formed by the machining equipment after rough processing and heat treatment.
  • the support part can prevent the deformation and damage of the main body material itself, which affects the target change and beam quality; the support frame adopts less forging procedures and heating times, the structure is uniform, the forging performance is good, and the raw materials are saved; the blank is heated before forging Treatment can reduce deformation resistance and improve plasticity; rough processing of the forged column can ensure the overall material performance of the support frame after heat treatment.
  • the material of the support frame is aluminum alloy, and the mass percentage of Cu element in the aluminum alloy is ⁇ 7%, which can meet the requirement of short half-life of radioisotopes generated after the support frame is activated by neutrons;
  • the tensile strength is ⁇ 150MPa
  • the yield strength is ⁇ 100MPa, which can satisfy the support of the main body of the beam shaping body by the support frame.
  • the aluminum alloy is a deformed aluminum alloy
  • the forging equipment is a free forging equipment
  • the free forging equipment includes upsetting and drawing equipment. Free forging changes the structure and properties of aluminum alloys through plastic forming methods, and at the same time can further save raw materials.
  • the heating equipment is a radiant resistance heating furnace with circulating air in the furnace, which can keep the temperature accurate and uniform, the furnace temperature deviation is ⁇ 10°C, the maximum forging temperature is 520°C, and the final forging temperature is 450°C , The allowable limit temperature is 530°C.
  • the heating time can be determined according to the dissolution of the strengthening phase and the homogenized structure. In this state, it has better plasticity and can improve the forging performance of aluminum alloy.
  • the main body includes a retarder, a reflector and a radiation shield, the retarder decelerates the neutrons generated from the neutron generator to the superthermal neutron energy zone, and the reflector surrounds
  • the retarder body guides neutrons that deviate from the main axis back to the main axis to increase the intensity of the superthermal neutron beam, and the radiation shield is used to shield the leaking neutrons and photons to reduce the non-irradiated area.
  • the support frame forms at least one containing unit, each containing at least a part of the main body.
  • the accommodating unit includes a first accommodating unit accommodating at least a part of the retarder body, the first accommodating unit is located at the center of the support frame in the radial direction, and the rough machining is performed between the column and the The corresponding area of the first containing unit is perforated. It is difficult to directly heat the column body to ensure the performance of the center material of the column body. Therefore, the center position of the column body obtained by forging (that is, the region corresponding to the column body and the first housing unit) is punched through rough machining, and then the depth is carried out.
  • Heat treatment can ensure that the support frame is close to the center position (the main frame part forming the first containing unit) and the overall material properties after heat treatment; at the same time, the first containing unit contains the retarder, which can ensure the support of the retarder at this time, Prevent deformation and damage of retarder body, affecting target change and beam quality.
  • the accommodating unit includes a second accommodating unit accommodating at least one of the retarder, reflector, and radiation shield
  • the support frame includes an outer wall and at least one inner wall that are circumferentially closed around the main shaft
  • the second accommodating unit is formed between the outer wall and the inner wall or the inner wall and the inner wall
  • the rough processing further includes preliminary processing of the area corresponding to the column and the second accommodating unit. It can be understood that the area corresponding to the column body and the second receiving unit may not be roughed to prevent the thin wall from being easily deformed when the heat treatment is performed after the roughing.
  • the heat treatment includes solution treatment and aging treatment.
  • the aluminum after the solution treatment is placed under a certain temperature and kept for a certain period of time, and the supersaturated solid solution will decompose, thereby causing the strength and hardness of the alloy to be greatly improved. .
  • a fifth aspect of the present invention provides a method for processing a beam shaping body support frame, including:
  • the support frame can prevent the deformation and damage of the main body material itself, which affects the target change and beam quality; the support frame adopts less forging procedures and heating times, uniform structure, good forging performance, and saving raw materials; heating the blank before forging
  • the treatment can reduce the deformation resistance and improve the plasticity; the central position of the forged column is punched before heat treatment, which can ensure that the support frame is close to the central position and the overall material performance after the heat treatment.
  • the blank is tested to meet the raw material requirements of the support frame material; before the forging step, the blank is processed to meet the processing requirements of the forging equipment; the forging is Free forging includes upsetting and drawing length.
  • the above two methods are repeated under the condition that the temperature of the forging is not lower than the specified temperature.
  • Static forging is carried out in accordance with the process to obtain precise grains within the structure.
  • the forging equipment has the ability to forge blanks.
  • the heat treatment includes solution treatment and aging treatment, the aluminum after solution treatment is placed under a certain temperature and kept for a certain period of time, the supersaturated solid solution will decompose, thereby causing the strength and hardness of the alloy to be greatly improved; Physical and chemical testing and inspection are performed after the heat treatment, including size testing, element testing, mechanical property testing, and ultrasonic flaw detection nondestructive testing.
  • the beam shaping body can prevent the deformation and damage of the beam shaping body material itself, and improve the flux and quality of the neutron radiation source.
  • Figure 1 is a schematic diagram of the boron neutron capture reaction
  • Figure 2 is the 10 B(n, ⁇ ) 7 Li neutron capture nuclear reaction equation
  • Figure 3 is a schematic diagram of a neutron capture therapy system according to an embodiment of the present invention.
  • FIG. 4 is a schematic diagram of a beam shaping body of a neutron capture therapy system according to an embodiment of the present invention.
  • FIG. 5 is a schematic diagram of the supporting part in FIG. 4;
  • Figure 6 is an exploded schematic diagram of the retarder in Figure 4.
  • Fig. 7 is a schematic diagram of the main frame in Fig. 5 viewed from the direction of the neutron beam N;
  • Fig. 8 is a schematic diagram of the main frame in Fig. 5 viewed from a direction opposite to the direction of the neutron beam N;
  • Fig. 9 is a flowchart of an embodiment of the main frame processing process in Fig. 5.
  • the neutron capture treatment system in this embodiment is preferably a boron neutron capture treatment system 100, which includes a neutron generator 10, a beam shaping body 20, a collimator 30 and a treatment table 40.
  • the neutron generator 10 includes an accelerator 11 and a target T.
  • the accelerator 11 accelerates charged particles (such as protons, deuterons, etc.) to produce a charged particle beam P such as a proton beam.
  • the charged particle beam P irradiates the target T and interacts with
  • the target material T acts to generate neutrons.
  • the neutrons form a neutron beam N.
  • the neutron beam N defines a main axis X.
  • the target material T is preferably a metal target material.
  • the direction of the neutron beam N in the figure and below does not represent the actual neutron movement direction, but the direction of the overall movement trend of the neutron beam N.
  • Select the appropriate nuclear reaction according to the required neutron yield and energy, the available accelerated charged particle energy and current size, and the physical and chemical properties of the metal target.
  • the nuclear reactions that are often discussed are 7 Li(p,n) 7 Be and 9 Be(p,n) 9 B, both of these reactions are endothermic reactions.
  • the energy thresholds of the two nuclear reactions are 1.881 MeV and 2.055 MeV, respectively.
  • the ideal neutron source for boron neutron capture therapy is superthermal neutrons with keV energy level, theoretically, if proton bombardment with an energy slightly higher than the threshold is used
  • the metallic lithium target can generate relatively low-energy neutrons and can be used in clinics without too much slowing treatment.
  • the two target materials of lithium metal (Li) and beryllium metal (Be) have proton interaction cross-sections with threshold energy Not high, in order to generate a large enough neutron flux, usually higher energy protons are used to initiate nuclear reactions.
  • the ideal target material should have the characteristics of high neutron yield, neutron energy distribution close to the super-thermal neutron energy region (described in detail below), no strong penetrating radiation, safe, cheap, easy to operate, and high temperature resistance.
  • the target material T may also be made of metal materials other than Li and Be, for example, Ta or W and alloys thereof.
  • the accelerator 11 may be a linear accelerator, a cyclotron, a synchrotron, or a synchrocyclotron.
  • the neutron source of the boron neutron capture therapy produces a mixed radiation field, that is, the beam contains low to high energy neutrons and photons; for the boron neutron capture therapy of deep tumors, except for the superthermal neutrons, the rest of the radiation
  • the human head tissue prosthesis is used for dose calculation, and the prosthetic beam quality factor is used as the neutron radiation
  • the design reference of the bundle will be described in detail below.
  • the International Atomic Energy Agency has given five recommendations for air beam quality factors for neutron sources for clinical boron neutron capture therapy. These five recommendations can be used to compare the pros and cons of different neutron sources and serve as Reference basis for selecting neutron generation methods and designing beam shaping bodies. The five recommendations are as follows:
  • Thermal neutron to epithermal neutron flux ratio thermal to epithermal neutron flux ratio ⁇ 0.05
  • the superthermal neutron energy range is between 0.5eV and 40keV, the thermal neutron energy range is less than 0.5eV, and the fast neutron energy range is greater than 40keV.
  • the neutron beam flux and the concentration of boron-containing drugs in the tumor jointly determine the clinical treatment time. If the concentration of boron-containing drugs in the tumor is high enough, the requirement for neutron beam flux can be reduced; conversely, if the concentration of boron-containing drugs in the tumor is low, high flux superthermal neutrons are required to give the tumor a sufficient dose.
  • the IAEA's requirement for the flux of the superthermal neutron beam is that the number of superthermal neutrons per square centimeter per second is greater than 10 9.
  • the neutron beam under this flux can roughly control the treatment of current boron-containing drugs Within one hour, short treatment time not only has advantages in patient positioning and comfort, but also can effectively utilize the limited residence time of boron-containing drugs in tumors.
  • fast neutrons can cause unnecessary normal tissue doses, they are regarded as pollution.
  • the dose is positively correlated with neutron energy. Therefore, the content of fast neutrons should be minimized in the design of neutron beams.
  • Fast neutron pollution is defined as the dose of fast neutrons per unit of superthermal neutron flux.
  • the IAEA's recommendation for fast neutron pollution is less than 2x 10 -13 Gy-cm 2 /n.
  • Gamma rays are strong penetrating radiation, which will non-selectively cause the dose deposition of all tissues in the beam path. Therefore, reducing the content of gamma rays is also a necessary requirement for neutron beam design.
  • Gamma-ray pollution is defined as the unit superheated neutron flux accompanying The IAEA’s recommendation for ⁇ -ray pollution is less than 2x 10 -13 Gy-cm 2 /n.
  • thermal neutrons Due to the fast attenuation speed and poor penetration ability of thermal neutrons, most of the energy is deposited in the skin tissue after entering the human body. Except for epidermal tumors such as melanoma, which need to use thermal neutrons as the neutron source for boron neutron capture therapy, it is targeted at the brain Deep tumors such as tumors should reduce thermal neutron content.
  • the IAEA recommends that the ratio of thermal neutron to superthermal neutron flux is less than 0.05.
  • the ratio of neutron current to flux represents the directionality of the beam. The larger the ratio, the better the forward direction of the neutron beam.
  • the high forward neutron beam can reduce the normal tissue dose caused by neutron divergence. It also improves the treatment depth and the flexibility of the posture.
  • the IAEA recommends that the ratio of neutron current to flux is greater than 0.7.
  • the prosthesis is used to obtain the dose distribution in the tissue, and the beam quality factors of the prosthesis are derived according to the dose-depth curve of the normal tissue and the tumor.
  • the following three parameters can be used to compare the therapeutic benefits of different neutron beams.
  • the tumor dose is equal to the depth of the maximum dose of normal tissue. After this depth, the dose of tumor cells is less than the maximum dose of normal tissue, that is, the advantage of boron neutron capture is lost. This parameter represents the penetration ability of the neutron beam. The larger the effective treatment depth, the deeper the tumor can be treated, and the unit is cm.
  • the effective treatment depth of tumor dose rate is also equal to the maximum dose rate of normal tissue. Because the total dose received by normal tissue is a factor that affects the total dose that can be given to the tumor, the parameter affects the length of the treatment time. The greater the effective treatment depth and the dose rate, the shorter the irradiation time required to give a certain dose to the tumor.
  • the unit is cGy/mA -min.
  • the effective treatment dose ratio received by the tumor and normal tissue is called the effective treatment dose ratio; the average dose can be calculated by integrating the dose-depth curve.
  • RBE Relative Biological Effectiveness
  • the neutron beam N generated by the neutron generator 10 is irradiated to the patient 200 on the treatment table 40 through the beam shaping body 20 and the collimator 30 in sequence.
  • the beam shaping body 20 can adjust the beam quality of the neutron beam N generated by the neutron generator 10, and the collimator 30 is used to converge the neutron beam N so that the neutron beam N has a higher Targeting.
  • the beam shaping body 20 further includes a supporting portion 21 (not shown in FIG. 1 and detailed below) and a main body portion 23 filled in the supporting portion 21.
  • the supporting portion 21 forms at least one containing unit C1-C4, each containing The unit accommodates at least a part of the main body part 23.
  • the supporting part can prevent the deformation and damage of the main body material itself, which affects the target change and beam quality.
  • the main body 23 includes a retarder 231, a reflector 232, and a radiation shield 233.
  • the neutrons generated by the neutron generator 10 have a wide energy spectrum. Except for the superthermal neutrons to meet the needs of treatment, it is necessary to reduce other types as much as possible. The neutron and photon content of the neutron to avoid harm to operators or patients.
  • the body 231 is made of materials with a large interaction cross section with fast neutrons and a small interaction cross section with superthermal neutrons, such as D 2 O, Al, AlF 3 , MgF 2 , CaF 2 , LiF, Li 2 CO 3 or Al 2 O At least one of 3 ; the reflector 232 surrounds the retarder 231, and reflects the neutrons diffused through the retarder 231 back to the neutron beam N to improve the utilization of neutrons.
  • the reflector 232 has a neutral Made of materials with strong sub-reflection ability, such as including at least one of Pb or Ni; the radiation shielding body 233 is used to shield the leaking neutrons and photons to reduce the normal tissue dose in the non-irradiated area, and the material of the radiation shielding body 233 It includes at least one of photon shielding materials and neutron shielding materials, such as photon shielding material lead (Pb) and neutron shielding material polyethylene (PE). It can be understood that the main body can also have other structures, as long as the superthermal neutron beam required for treatment can be obtained.
  • the target T is arranged between the accelerator 11 and the beam shaping body 20.
  • the accelerator 11 has a transmission tube 111 for transmitting the charged particle line P.
  • the transmission tube 111 extends along the direction of the charged particle line P and enters the beam shaping body 20. , And sequentially pass through the retarder 231 and the reflector 232, the target T is set in the retarder 231 and at the end of the transmission tube 111 to obtain a better neutron beam quality.
  • the first and second cooling tubes D1 and D2 are arranged between the transmission tube 111 and the retarder 231 and the reflector 232. One end of the first and second cooling tubes D1 and D2 are respectively connected to the cooling target T The inlet (not shown) is connected to the cooling outlet (not shown), and the other end is connected to an external cooling source (not shown). It can be understood that the first and second cooling pipes can also be arranged in the beam shaping body in other ways, and when the target is placed outside the beam shaping body, it can also be eliminated.
  • the supporting portion 21 includes an outer wall 211 circumferentially closed around the main axis X and first and second side plates 221, 222 respectively arranged on both sides of the outer wall 211 along the neutron beam N direction and connected to the outer wall 211 ,
  • the first side plate 221 is provided with a hole 2211 through which the transmission tube 111 passes, and the second side plate 222 is provided with a hole 2221 forming a beam exit, and a receiving portion is formed between the outer wall 211 and the first and second side plates 221, 222 C, the main body part 23 is arranged in the accommodating part C.
  • the accommodating part C includes at least one accommodating unit C1-C4 (detailed below), each accommodating unit C1-C4 accommodates at least one of the retarder 231, the reflector 232 and the radiation shielding body 233, and at least one accommodating unit C1- C4 contains at least two of the retarder, the reflector and the radiation shield at the same time or contains at least two different materials at the same time. It can be understood that the first and second side plates may not be provided, and the receiving part is surrounded by the outer wall.
  • the supporting portion 21 also includes at least one inner wall which is circumferentially closed around the main axis X and extends between the first and second side plates 221 and 222.
  • the first and second inner walls 212 and 213 are respectively arranged radially inward. , Define the radial direction as the direction perpendicular to the main axis X.
  • the supporting part 21 also includes a first horizontal plate 223 arranged between the first and second side plates 221 and 222 along the neutron beam N direction, and is circumferentially closed around the main axis X and extends between the first horizontal plate 223 and the first side.
  • the third inner wall 214 between the plates 221 and the fourth inner wall 215 circumferentially closed around the main axis X and extending from the first horizontal plate 223 to the second side plate 222.
  • the third inner wall 214 is radially closer to the main axis X than the second inner wall 213, the fourth inner wall 215 is located between the second inner wall 213 and the third inner wall 214 in the radial direction, and the first transverse plate 223 extends between the third inner wall 214 and the fourth inner wall 214.
  • the inner surface of the third inner wall 214 and the side wall of the hole 2211 on the first side plate 221 are on the same surface, and the third inner wall 214 forms the installation part of the transmission pipe 111, the first and second cooling pipes D1, D2, etc.
  • a second transverse plate 224 is provided between the fourth inner wall 215 and the second side plate 222 adjacent to the fourth inner wall 215.
  • the second transverse plate 224 extends radially inward from the second inner wall 213, and the second transverse The plate 224 is provided with a hole 2241 through which the neutron beam N passes.
  • the inner wall of the hole 2241 is closer to the main axis X than the inner side of the fourth inner wall 215.
  • the second horizontal plate may not be provided, and the first horizontal plate may extend to the outer wall or other inner walls, and multiple horizontal plates may also be provided between the outer wall and the inner wall, and between the inner wall and the inner wall.
  • the beam shaping body is cylindrical as a whole, the cross-sections of the outer wall and the inner wall in the direction perpendicular to the main axis X are rings around the main axis X and extend parallel to the main axis X, and the side plates and horizontal plates are both perpendicular to the main axis X.
  • the flat plate extending from the main shaft X can also have other settings, such as the extension direction is inclined to the main shaft, and the outer contour of the outer wall in the direction perpendicular to the main shaft can also be square, rectangular or polygonal, which is convenient for transportation and installation.
  • a first accommodating unit C1 is formed between the outer wall 211, the first inner wall 212, the first side plate 221, and the second side plate 222.
  • a second accommodating unit C2 is formed between the second inner wall 213, the third inner wall 214, the fourth inner wall 215, the first side plate 221, the first horizontal plate 223, and the second horizontal plate 224 to form a third accommodating unit C3.
  • a PE block 241 of corresponding shape is arranged in the first accommodating unit C1; a lead block 242 and a PE block 241 are sequentially arranged in the second accommodating unit C2 along the neutron beam N direction, and the volume ratio of the lead block to the PE block is less than Equal to 10, the interface between the lead block and the PE block is perpendicular to the N direction of the neutron beam. It can be understood that it can also be in other proportions or other distributions.
  • the radiation shielding body 233 includes a neutron shielding body and a photon shielding body.
  • the PE block 241 serves as a neutron shielding body
  • the lead block 242 serves as a reflector 232 and a photon shielding body at the same time.
  • the third containing unit C3 is provided with a lead block 242, an aluminum alloy block 243, a Teflon block 244, and a PE block 241.
  • the aluminum alloy block 243 and the Teflon block 244 are integrally arranged to include at least one cone shape.
  • the PE block 241 is arranged adjacent to the second horizontal plate 224, and the lead block 242 fills the remaining area.
  • the aluminum alloy block 243 and the Teflon block 244 divide the lead block 242 in the third receiving unit C3 into two parts as a whole.
  • the aluminum alloy block 243 and the Teflon block 244 are used as the first and second supplementary parts of the retarder 231, which can reduce the manufacturing cost of the retarder, and at the same time, it will not have a large impact on the beam quality.
  • the whole arrangement with the second supplementary part includes at least one cone shape, which can obtain better beam quality and treatment effect.
  • the Teflon block 244 also has a better fast neutron absorption effect and can reduce the fast neutron content in the beam.
  • the lead block 242 serves as a reflector 232 and a photon shield at the same time.
  • the PE block 241 serves as a neutron shield, and it is understandable that the PE block may not be provided.
  • an aluminum alloy block 243 and a Teflon block 244 are sequentially arranged along the neutron beam N direction, and the aluminum alloy block 243 and the Teflon block 244 are integrally arranged into two cones adjacent to each other in opposite directions
  • the aluminum alloy block 243 itself is also arranged in the shape of two cones adjacent to each other in opposite directions.
  • the aluminum alloy block 243 includes a first cone portion 2431 and a second cone portion 2432 sequentially arranged along the neutron beam N direction.
  • the radial dimension of the outer contour of a cone portion 2431 gradually increases along the overall trend of the neutron beam N direction.
  • the second cone portion 2432 is at the maximum radial dimension of the outer contour of the first cone portion 2431 and the first cone portion 2431
  • the portion 2431 is connected, and the radial dimension of the outer contour of the second cone portion 2432 gradually decreases along the overall trend of the neutron beam N direction.
  • the Teflon block 244 is adjacent to the second cone portion 2432 at the point where the radial dimension of the outer contour of the second cone portion 2432 is the smallest.
  • the radial size of the outer contour of the Teflon block 244 gradually decreases along the neutron beam N direction.
  • contact with the PE block 241 at the smallest radial dimension of the outer contour.
  • the cross-sectional contours of the aluminum alloy block 243 and the Teflon block 244 along the plane where the main axis X is located are irregular quadrilaterals or polygons.
  • the aluminum alloy block 243 has a first side A1 in contact with the lead block 242 in the first cone portion 2431, a second side A2 in contact with the lead block 242 in the second cone portion 2432, and a second side A2 in contact with the Teflon block 244.
  • the third side A3 has a fourth side A4 in contact with the third inner wall 214, the fourth inner wall 215 and the first horizontal plate 223 in the first and second cone parts.
  • the fourth side A4 is a step surface.
  • the Teflon block 244 has a fifth side A5 in contact with the aluminum alloy block 243, a sixth side A6 in contact with the lead block 242, a seventh side A7 in contact with the fourth inner wall 215, and an eighth side in contact with the PE block 241 A8.
  • the third side A3 and the fifth side A5 are adjacent to each other and serve as the interface between the aluminum alloy block 243 and the Teflon block 244.
  • the interface is perpendicular to the neutron beam N direction.
  • the volume ratio of the aluminum alloy block 243 and the Teflon block 244 is 5-20. It can be understood that according to the neutron beam required for treatment, such as different irradiation depths, other ratios or other distributions can also be used.
  • the magnesium fluoride block 245 is provided as the basic part of the retarder 231 in the fourth accommodating unit C4.
  • the magnesium fluoride block 245 contains Li-6 and can be used as a thermal neutron absorber at the same time.
  • the first and second supplementary parts of the retarder in the storage unit C3 surround the basic portion of the retarder provided in the fourth storage unit C4.
  • the magnesium fluoride block 245 is cylindrical as a whole, including first and second end faces A9 and A10 that are substantially perpendicular to the direction of the neutron beam N.
  • the first and second end faces A9 and A10 are arranged in sequence along the neutron beam direction.
  • the first end face A9 Facing the first side plate 221, a central hole 2451 is provided.
  • the central hole 2451 is used to accommodate the transfer pipe 111, the first and second cooling pipes D1, D2 and the target material T.
  • the central hole 2451 is a cylindrical hole, and the side wall of the central hole 2451a is on the same surface as the inner surface of the third inner wall.
  • the radial distance L1 from the third inner wall 214 to the main axis X is smaller than the radial distance L2 from the fourth inner wall 215 to the main axis X, so that the basic part of the retarder 231 surrounds the target T, so that the neutrons generated by the target T can be effectively slowed down in all directions, which can further improve the neutron flux and beam quality.
  • a lead plate 246 is set between the magnesium fluoride block 245 and the second horizontal plate 224. The lead plate 246 serves as a photon shield.
  • the lead can absorb the gamma rays released from the retarder, and the lead plate 246 is in the neutron beam N direction
  • the thickness is less than or equal to 5cm and will not reflect the neutrons passing through the retarder. It is understandable that other settings are also possible.
  • the magnesium fluoride block 245 does not contain Li-6, but the magnesium fluoride block 245 and the second A separate thermal neutron absorber composed of Li-6 is arranged between the two horizontal plates 224, and the lead plate can also be eliminated.
  • the PE as the neutron shield in this embodiment can be replaced with other neutron shielding materials; the lead as the photon shield can be replaced with other photon shielding materials; the lead as the reflector can be replaced with other neutron reflection capabilities Strong material; magnesium fluoride, which is the basic part of the retarder, can be replaced with other materials with a large fast neutron cross section and a small superthermal neutron cross section; Li-6 as a thermal neutron absorber can be replaced with other materials A material with a large cross-section with thermal neutrons; the aluminum alloy as the first supplementary part of the retarder can be replaced with at least one of Zn, Mg, Al, Pb, Ti, La, Zr, Bi, Si, and C Materials, the selection of easily available materials can reduce the manufacturing cost of the retarder, and at the same time has a certain neutron retarding effect, which will not have a greater impact on the beam quality; as the second supplementary part of the retarder Flon can be replaced with graphite, etc.
  • the second supplement part uses a material with a better fast neutron absorption effect than the first supplement part, which can reduce the fast neutron content in the beam. It can be understood that at least two of the first and second supplementary parts and the basic part of the retarder can also be made of the same material.
  • the support part 21 is further provided with a radial partition 210.
  • the plane on which the radial partition 210 is located extends through the main shaft X, and divides each containing unit C1-C3 into at least two sub-regions in the circumferential direction. Therefore, the PE block, the lead block, the aluminum alloy block, and the graphite block arranged in each containing unit C1-C3 are divided into at least two sub-modules in the circumferential direction.
  • the first radial partition 2101 is provided between the first side plate 221 and the second side plate, and extends from the outer wall 211 to the second inner wall 213; the second radial partition 2102 is provided on the first side plate Between 221 and the second horizontal plate 224, it extends from the second inner wall 213 to the third inner wall 214 or the fourth inner wall 215.
  • the directional baffles and four of the first radial baffles are on the same plane; it can be understood that the radial baffles may also have other numbers or arrangements, or no radial baffles may be provided.
  • the radial partition 210, the outer wall 211, the first transverse plate 223 and the first, second, third, and fourth inner walls 212-215 are integrated.
  • the material is aluminum alloy and has Good mechanical properties and short half-life of radioisotopes produced by neutron activation.
  • the casting process can be used, and the supporting mold is integrally formed.
  • the template is wooden or aluminum mold, and the sand core can be red sand or resin sand.
  • the specific process is a common method in the industry. Since casting will be accompanied by a draft angle, according to the design and beam quality requirements, machining needs to remove them all.
  • the structure and casting process make the frame structure have the advantages of good integrity, high rigidity and high bearing capacity. Taking into account the limitations of the machining tool and the stress concentration on the right-angle side, all corners are rounded. It can also be plate rolling welding or forging an aluminum alloy cylinder first, and then machining the cylinder to form.
  • the main frame 21a is made of 6061 aluminum alloy, which can meet the requirements of the chemical composition and mechanical properties of the main frame material.
  • the types of aluminum alloy constituent elements and the mass ratio of each element should be controlled, such as the mass percentage of Cu element ⁇ 7%.
  • the chemical composition of the main frame material selected in this implementation meets Cu ⁇ 1.0%, Mn ⁇ 1.5%, Zn ⁇ 1.0% (mass percentage); the chemical composition table of 6061 aluminum alloy is shown in Table 1, for comparison It can be seen that 6061 aluminum alloy can meet the chemical composition required by the main frame 21a material.
  • the mechanical properties of the main frame need to meet the requirements; according to CAE simulation calculation and empirical adjustments, the tensile strength of the aluminum alloy main frame is selected in this implementation to be ⁇ 150MPa, and the yield strength ⁇ 100MPa.
  • the free forging method is adopted in this embodiment to change the structure and performance of the aluminum alloy through the plastic forming method, and at the same time save raw materials.
  • the quality of the forging largely depends on the metal structure obtained during the deformation process, especially the uniformity of the forging deformation. Because of the uneven deformation, not only the plasticity of the metal is reduced, but also due to the uneven recrystallization, an uneven structure will be obtained, which will make the performance of the forging worse. In order to obtain a uniform deformed structure and the best mechanical properties, the fewer the procedures, the less Well, the fewer heating times, the better.
  • the processing process of this embodiment is as follows:
  • Billet preparation aluminum factories and other manufacturers process aluminum ore into aluminum ingots, cast them into billets, and prepare them to meet the national standard 6061 aluminum alloy composition.
  • the billets are tested, such as alloy grades, melting furnaces, batch numbers, specifications, Data and experimental results of homogenization annealing, low power and oxide film inspection;
  • Blanking processing the blanks that meet the requirements by cutting, sawing, gas cutting, etc., such as face cutting, and timely removal of burrs, oil stains and sawdust to meet the processing needs of forging equipment;
  • Heating heat the blank before forging to reduce deformation resistance and improve plasticity. If a radiant resistance heating furnace is used, the furnace is equipped with circulating air, which can keep the temperature accurate and uniform, and the temperature deviation of the furnace can be controlled within the range of ⁇ 10°C. In this embodiment, the maximum forging temperature is 520°C, and the final forging temperature It is 450°C, and the allowable limit temperature is 530°C. It is understood that other heating devices can also be used. The determination of the heating and holding time should fully consider the thermal conductivity of the alloy, the specifications of the billet, and the heat transfer mode of the heating equipment. In this embodiment, the heating time is determined according to the dissolution of the strengthening phase and the homogenization of the structure.
  • the billet can also be heated before cutting in step 2. At this time, the billet should be cleaned of oil, debris and other dirt before heating, such as before entering the heating furnace, to avoid polluting the air in the furnace.
  • the material of 6061 aluminum alloy is polycrystalline. There are grain boundaries between the grains, and there are sub-grain and phase boundaries inside the grains. Therefore, the plasticity of the material is used to produce plastic deformation with the help of external force. , To be able to obtain forgings with the required shape (such as cylinder), size and certain organizational properties.
  • the forging deformation eliminates the as-cast structure of the metal blank and greatly improves the plasticity and mechanical properties.
  • free forging methods are used, such as upsetting and drawing, and the above two methods are repeated under the condition that the temperature of the forging is not lower than the specified temperature, and static forging is performed according to the process to obtain precise grains in the structure.
  • the forging equipment has the precision of forging the blank.
  • the cylinder is obtained by forging in step 4, and the cylinder is directly heat-treated, which makes it difficult to ensure the performance of the central material of the cylinder. Therefore, the central position of the forging cylinder (that is, the area corresponding to the fourth accommodating unit C4) is punched through rough machining, and then deep heat treatment is performed to ensure that the main frame is close to the central position after heat treatment (forming the fourth The main frame part of the accommodating unit C4) and the overall material properties; at the same time, the fourth accommodating unit C4 accommodates the basic part of the retarder.
  • rough machining may also include preliminary machining of the hollow area between the outer wall 211 and the inner wall 212-215 of the main frame (that is, the area corresponding to the column and the first, second, and third housing units C1, C2, C3). , Such as drilling, milling, cutting and forging to obtain the solid part of the cylinder in the area; in this embodiment, the area is not roughed to prevent heat treatment after roughing, the wall thickness is thin and easy to deform. In the case that the process can guarantee the material properties of the central area and other areas, it is not necessary to do rough machining; there should be a margin for rough machining for subsequent further machining.
  • the heat treatment process used in this embodiment is T6 (Solid Solution + Aging).
  • Solution treatment is the precedent process for precipitation hardening of the alloy.
  • the solid solution formed during solid solution is rapidly cooled to obtain a metastable supersaturated solid solution, which creates conditions for natural aging and artificial aging, and significantly improves strength and hardness.
  • aging treatment is needed. Put the aluminum after solution treatment under a certain temperature and keep it for a certain period of time.
  • the supersaturated solid solution will decompose, which will cause the strength and hardness of the alloy to increase greatly. It can be room temperature. Keep or heat.
  • Aging treatment is the last process of heat treatment, which can improve and determine the final mechanical properties of aluminum alloy.
  • the heating temperature and holding time can be selected according to the actual situation. It can be understood that other heat treatment processes can also be used, as long as the mechanical properties required for use can be met.
  • Physical and chemical testing and inspection After the heat treatment is completed, physical and chemical testing and testing are required, including size testing, element testing, mechanical property testing, ultrasonic flaw detection and non-destructive testing. It can be the inspection performed by the heat treatment personnel after the heat treatment, or the inspection by the mechanical processing (see below) before the mechanical processing.
  • the mechanical performance test can be performed by cutting part of the material in the relevant area of the workpiece after heat treatment.
  • the part that is punched at the center position during rough machining can be heat treated at the same time, and the detection of this part is approximately representative of the position close to the spindle X
  • the performance of the inner walls 214, 215; the area between the outer wall 211 and the inner walls 212-215 is tested by cutting the heat-treated forged cylinder in the area. It can be understood that when the hollow area between the outer wall 211 and the inner wall 212-215 is rough-processed, the rough-cut part of the area can also be inspected after heat treatment at the same time, which can also approximately represent the performance of the area. The selection can be marked on the drawing. The above-mentioned area is sampled for mechanical experiments to obtain the yield strength and tensile strength.
  • the non-destructive testing adopts ultrasonic flaw detection, which can be a comprehensive inspection or a partition inspection. In this embodiment, the ultrasonic flaw detection is performed on the inner wall near the center.
  • the main frame 21a and the second horizontal plate 224 are connected by bolts.
  • the first threaded hole is uniformly machined on the end surface of the fourth inner wall 215 facing the second side plate 222, and the position on the second horizontal plate 224 corresponds to the first threaded hole.
  • the first through hole is uniformly machined on the upper side, and the bolt passes through the first through hole to connect with the first threaded hole.
  • the aperture of the first through hole is slightly larger than the aperture of the first threaded hole, and the number of the first threaded hole and the first through hole only needs to satisfy the connection strength.
  • the first and second side plates 221, 222 and the second horizontal plate 224 are made of lead-antimony alloy materials.
  • the outer contours of the first and second side plates 221 and 222 are consistent with the outer contour of the outer wall 211.
  • the first and second side plates 221, 222 and the second horizontal plate 224 are connected to the main frame by bolts.
  • the end faces of the inner wall of the main frame 21a facing the first, second and second horizontal plates are respectively uniformly machined.
  • Two threaded holes, the second through holes are uniformly machined at the positions corresponding to the second threaded holes on the first, second side plates 221, 222 and the second horizontal plate 224.
  • the second through hole The aperture is slightly larger than the aperture of the second threaded hole, and the number of the second threaded holes and the second through holes only needs to meet the connection strength.
  • the materials of the main frame, side plates, and end plates (second horizontal plates) in this embodiment have a certain strength and the radioisotopes generated after activation by neutrons have a short half-life (such as less than 7 days).
  • the material performance can satisfy the support beam shaping body, such as aluminum alloy, titanium alloy, lead antimony alloy, cobalt-free steel, carbon fiber, PEEK, polymer, etc.; side plate, end plate (second horizontal plate)
  • Other detachable connections or non-detachable connections can be used with the main frame. When the detachable connection is adopted, it is convenient to replace various parts of the main body.
  • the supporting part of the beam shaping body and the main body part filled in the supporting part can also have other structures.
  • the main frame 21a During construction, first put the main frame 21a in the mounting hole reserved for the beam shaping body support part, and connect the outer wall 211 of the main frame 21a and the beam shaping body support part with bolts or the like. Then carry out the filling of the main body and the installation of the first and second side plates and the second horizontal plate. Due to the low density of PE, aluminum alloy and graphite, the corresponding area can be filled as a whole; because the lead is relatively heavy, it can be installed along the neutron The N-direction of the beam is divided into pieces manually, or with the aid of a mechanical overall filling; magnesium fluoride can also be filled in whole or in pieces. After the beam shaping body is installed, install the transmission tube, target, collimator and other components.
  • the collimator 30 is installed behind the beam exit, and the superthermal neutron beam from the collimator 30 irradiates the patient 200 , After passing through the superficial normal tissues, they are slowed down to thermal neutrons to reach tumor cells M.
  • the collimator is fixed to the main frame 21a by bolts, etc.
  • a third threaded hole is reserved on the end surface of the second inner wall 213 facing the second side plate, and the second side plate 222 corresponds to the third threaded hole
  • the third through hole is machined uniformly in position. Considering the bolt assembly, the diameter of the third through hole is slightly larger than that of the third threaded hole, and the number of third threaded holes and third through holes can meet the connection strength.
  • the collimator 30 can also be fixed by other connection methods, and the collimator 30 can also be eliminated or replaced by other structures, and the neutron beam exits the beam exit to directly irradiate the patient 200.
  • a radiation shielding device 50 is further provided between the patient 200 and the beam exit to shield the radiation from the beam exit to the normal tissue of the patient. It is understandable that the radiation shielding device 50 may not be provided.
  • the "cylinder” or “cylinder-shaped” in the embodiment of the present invention refers to a structure whose overall trend of the outer contour is basically unchanged from one side to the other side of the direction shown in the figure.
  • One of the outer contours The line can be a line segment, such as a corresponding contour line in a cylindrical shape, or a circular arc close to the line segment with a larger curvature, such as a corresponding contour line in a spherical shape with a larger curvature.
  • the entire surface of the outer contour can be smooth Transitions can also be non-smooth transitions, for example, many protrusions and grooves are made on the surface of a cylinder or a spherical body with a larger curvature.
  • the "cone” or “cone-shaped” in the embodiment of the present invention refers to a structure whose outer contour gradually becomes smaller from one side to the other side in the direction shown in the figure.
  • One of the outer contours The line can be a line segment, such as a cone-shaped corresponding contour line, or a circular arc, such as a spherical corresponding contour line.
  • the entire surface of the outer contour can be smooth or non-smooth transition, such as Many protrusions and grooves are made on the cone-shaped or spherical surface.

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Abstract

L'invention concerne un système de thérapie par capture de neutrons, qui peut éviter la déformation et la dégradation d'un matériau de corps de mise en forme de faisceau en lui-même, et peut améliorer le flux et la qualité d'une source de neutrons. Le système (100) de thérapie par capture de neutrons de bore comprend un appareil (10) de génération de neutrons et un corps (20) de mise en forme de faisceau, l'appareil (10) de génération de neutrons comprenant un accélérateur (11) et un matériau cible (T) ; un faisceau de particules chargées (P) généré au moyen de l'accélération de l'accélérateur (11) interagissant avec le matériau cible (T) pour générer des neutrons ; les neutrons formant un faisceau de neutrons (N) et le faisceau de neutrons (N) définissant un axe principal (X) ; et le corps (20) de mise en forme de faisceau comprenant une partie de support (21) et une partie (23) de corps principal chargée dans la partie de support (21).
PCT/CN2020/079653 2019-04-17 2020-03-17 Système de thérapie par capture de neutrons WO2020211581A1 (fr)

Priority Applications (7)

Application Number Priority Date Filing Date Title
EP20791113.2A EP3957362A4 (fr) 2019-04-17 2020-03-17 Système de thérapie par capture de neutrons
JP2021559125A JP7312850B2 (ja) 2019-04-17 2020-03-17 中性子捕捉療法システム
AU2020260204A AU2020260204B2 (en) 2019-04-17 2020-03-17 Neutron capture therapy system
CA3135517A CA3135517C (fr) 2019-04-17 2020-03-17 Systeme de therapie par capture de neutrons
US17/494,874 US12011615B2 (en) 2019-04-17 2021-10-06 Neutron capture therapy system
JP2023112730A JP2023123865A (ja) 2019-04-17 2023-07-10 中性子捕捉療法システム
AU2023270215A AU2023270215A1 (en) 2019-04-17 2023-11-21 Neutron capture therapy system

Applications Claiming Priority (6)

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CN201910308298.5 2019-04-17
CN201910308039 2019-04-17
CN201910308298.5A CN111821581A (zh) 2019-04-17 2019-04-17 中子捕获治疗系统及用于中子捕获治疗系统的射束整形体
CN201910308039.2 2019-04-17
CN201910623203.9 2019-07-11
CN201910623203.9A CN111821584A (zh) 2019-04-17 2019-07-11 中子捕获治疗系统及用于中子捕获治疗系统的射束整形体

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023045327A1 (fr) * 2021-09-26 2023-03-30 散裂中子源科学中心 Corps de mise en forme de ligne de faisceau pour thérapie par capture de neutrons

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006047115A (ja) * 2004-08-04 2006-02-16 Mitsubishi Heavy Ind Ltd 中性子発生装置及びターゲット、並びに中性子照射システム
CN104771837A (zh) * 2015-04-03 2015-07-15 中国中原对外工程有限公司 一堆三照射座布局的抗癌核素中子刀
CN107802968A (zh) * 2017-11-24 2018-03-16 北京新核医疗科技有限公司 减速过滤装置及中子放射治疗系统
CN107998517A (zh) * 2016-10-31 2018-05-08 南京中硼联康医疗科技有限公司 中子捕获治疗系统
CN108136200A (zh) * 2015-05-06 2018-06-08 中子医疗股份有限公司 用于硼中子俘获治疗的中子靶
CN108926784A (zh) * 2017-05-26 2018-12-04 南京中硼联康医疗科技有限公司 中子捕获治疗系统及用于粒子线产生装置的靶材
CN208335758U (zh) * 2018-06-20 2019-01-04 新奥科技发展有限公司 一种防护装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006047115A (ja) * 2004-08-04 2006-02-16 Mitsubishi Heavy Ind Ltd 中性子発生装置及びターゲット、並びに中性子照射システム
CN104771837A (zh) * 2015-04-03 2015-07-15 中国中原对外工程有限公司 一堆三照射座布局的抗癌核素中子刀
CN108136200A (zh) * 2015-05-06 2018-06-08 中子医疗股份有限公司 用于硼中子俘获治疗的中子靶
CN107998517A (zh) * 2016-10-31 2018-05-08 南京中硼联康医疗科技有限公司 中子捕获治疗系统
CN108926784A (zh) * 2017-05-26 2018-12-04 南京中硼联康医疗科技有限公司 中子捕获治疗系统及用于粒子线产生装置的靶材
CN107802968A (zh) * 2017-11-24 2018-03-16 北京新核医疗科技有限公司 减速过滤装置及中子放射治疗系统
CN208335758U (zh) * 2018-06-20 2019-01-04 新奥科技发展有限公司 一种防护装置

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023045327A1 (fr) * 2021-09-26 2023-03-30 散裂中子源科学中心 Corps de mise en forme de ligne de faisceau pour thérapie par capture de neutrons

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