CN106975162B - Neutron capture therapy system - Google Patents
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Classifications
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- G—PHYSICS
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- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
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- G01T3/06—Measuring neutron radiation with scintillation detectors
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- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N5/1048—Monitoring, verifying, controlling systems and methods
- A61N5/1064—Monitoring, verifying, controlling systems and methods for adjusting radiation treatment in response to monitoring
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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
- A61N5/103—Treatment planning systems
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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
- A61N5/1048—Monitoring, verifying, controlling systems and methods
- A61N5/1071—Monitoring, verifying, controlling systems and methods for verifying the dose delivered by the treatment plan
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- G01T3/00—Measuring neutron radiation
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- A—HUMAN NECESSITIES
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- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N2005/1085—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy characterised by the type of particles applied to the patient
- A61N2005/109—Neutrons
Abstract
An aspect of the present invention is to provide a radiation detection system for a neutron capture therapy system that improves accuracy of a neutron beam irradiation dose of the neutron capture therapy system and enables finding a failure site in time, wherein the neutron capture therapy system includes a charged particle beam, a charged particle beam inlet for passing the charged particle beam, a neutron generating section for generating a neutron beam through a nuclear reaction with the charged particle beam, a beam shaping body for adjusting a neutron beam flux and quality generated by the neutron generating section, and a beam outlet adjacent to the beam shaping body, wherein the radiation detection system includes a radiation detection device for detecting gamma rays instantaneously emitted after the neutron beam irradiation in real time. Another aspect of the present invention is to provide a radiation detection method for a neutron capture therapy system that improves accuracy of a neutron beam irradiation dose of the neutron capture therapy system and enables timely finding of a failure site.
Description
Technical Field
The present invention relates to radiation therapy systems, and more particularly to neutron capture therapy systems.
Background
With the development of atomic science, radiation therapy such as cobalt sixty, linac, electron beam, etc. has become one of the main means for cancer therapy. However, the traditional photon or electron treatment is limited by the physical condition of the radioactive rays, and a large amount of normal tissues on the beam path can be damaged while killing tumor cells; in addition, due to the different sensitivity of tumor cells to radiation, traditional radiotherapy often has poor therapeutic effects on malignant tumors with relatively high radiation resistance (such as glioblastoma multiforme (glioblastoma multiforme) and melanoma (melanoma)).
In order to reduce radiation damage to normal tissue surrounding a tumor, the concept of target treatment in chemotherapy (chemotherapy) has been applied to radiotherapy; for tumor cells with high radiation resistance, radiation sources with high relative biological effects (relative biological effectiveness, RBE) such as proton therapy, heavy particle therapy, neutron capture therapy, etc. are also actively developed. The neutron capture treatment combines the two concepts, such as boron neutron capture treatment, and provides better cancer treatment selection than the traditional radioactive rays by means of the specific aggregation of boron-containing medicaments in tumor cells and the accurate neutron beam regulation.
Boron neutron capture therapy (Boron Neutron Capture Therapy, BNCT) is carried out by using boron-containing 10 B) The medicine has the characteristic of high capture section for thermal neutrons by 10 B(n,α) 7 Li neutron capture and nuclear fission reaction generation 4 He (He) 7 Li two heavy charged particles. Referring to FIGS. 1 and 2, schematic and schematic diagrams of a boron neutron capture reaction are shown, respectively 10 B(n,α) 7 The Li neutron capture nuclear reaction equation has the average energy of two charged particles of about 2.33MeV, high linear transfer (Linear Energy Transfer, LET) and short range characteristics, and the linear energy transfer and range of alpha particles are 150keV/μm and 8 μm respectively 7 The Li heavy charged particles are 175 keV/mum and 5μm, the total range of the two particles is approximately equal to one cell size, so that the radiation injury caused to organisms can be limited at the cell level, and when boron-containing medicaments are selectively gathered in tumor cells, the purpose of killing the tumor cells locally can be achieved on the premise of not causing too great injury to normal tissues by matching with a proper neutron source.
Beam detection and diagnosis in neutron capture therapy systems is an important issue, directly related to the dose and effect of radiation therapy. Conventionally, there has been disclosed a neutron capture therapy system in which, for example, a gold wire for neutron beam measurement is attached to an irradiation subject in advance, the gold wire is removed during irradiation of a neutron beam, and the radiation dose of the neutron beam during irradiation is measured by measuring the radiation dose of the gold wire. And controlling (e.g., stopping, etc.) the neutron capture therapy system based on the measured irradiation dose so that the neutron beam is irradiated to the irradiation subject at the planned irradiation dose.
However, in this case, if the irradiation dose rate of the neutron beam varies after the irradiation amount of the gold wire is measured for some reason, it cannot sufficiently cope with such variation, and it may become difficult to irradiate the neutron beam to the irradiation subject at the planned irradiation dose. That is, in the neutron capture therapy system described above, the irradiation dose of the radiation cannot be detected in real time. In addition, once the detection equipment fails, the source of the failure cannot be quickly judged at all, so that time and labor are consumed in failure detection.
Accordingly, there is a need for a neutron capture treatment system that improves the accuracy of treatment planning.
Disclosure of Invention
An aspect of the present invention is to provide a radiation detection system for a neutron capture therapy system that improves accuracy of a neutron beam irradiation dose of the neutron capture therapy system and enables finding a fault location in time, wherein the neutron capture therapy system includes a charged particle beam, a charged particle beam inlet for passing the charged particle beam, a neutron generating section for generating a neutron beam through a nuclear reaction with the charged particle beam, a beam shaping body for adjusting a neutron beam flux and quality generated by the neutron generating section, and a beam outlet adjacent to the beam shaping body, and the neutron capture therapy system corrects a nonlinear relationship between a boron concentration and a tumor dose.
Preferably, the neutron capture therapy system comprises a radiation detection system, the radiation detection system comprises a radiation detection device and a control device, the radiation detection device is used for detecting gamma rays which are instantaneously emitted after being irradiated by neutron beams in real time, and the control device sends out a human perception signal according to the detection result of the radiation detection device so as to confirm the next operation of the neutron capture therapy system. The human-perceived signal may be a signal that is perceived by a human functional device such as auditory, visual, tactile, or olfactory, such as one or more of an audible alarm, a warning light, vibration, or a pungent odor.
The term "gamma rays which are instantaneously emitted after being irradiated with a neutron beam" means gamma rays generated when a neutron beam is reacted with other elements, such as elements which are known in the art to generate gamma rays when a neutron capturing nuclear reaction occurs, but other elements are not limited to boron-10 elements. In the embodiment of the invention, the 'gamma rays instantaneously emitted after the neutron beam irradiates' are gamma rays generated when the neutron beam and the boron-10 element generate boron neutron capture reaction.
The neutron capture treatment system further comprises an accelerator for accelerating the charged particle beam, the control device comprises a control part and a display part, the control part displays the detection result of the radiation detection system through the display part and feeds back the detection result to the accelerator to confirm the next operation of the accelerator, and the display part can be common display equipment such as a television or a liquid crystal display.
The radiation detection device is a free chamber or a scintillation detector for detecting gamma rays, and the radiation detection system calculates the boron concentration value through the detected gamma signals.
Common radiation detection systems capable of realizing real-time detection have two different detection principles of an ionization chamber and a scintillation detector. Wherein, when gamma rays are detected, one mode can adopt an ionization chamber as an inflatable ionization chamber; another approach may be to employ a scintillation detector.
Preferably, the boron concentration value is calculated using formula a:
wherein B (t) is the boron concentration value at time t in ppm, time t in s, k is the measured value, and GC (t) is the gamma count of the detected preset energy interval minus the gamma count of the background at time t; the k is calculated by adopting a formula B:
wherein B (t) 0 ) For time t 0 Boron concentration in ppm, time t 0 Is in units of s, GC (t 0 ) For time t 0 Gamma total count for a preset energy interval is detectedSubtracting the gamma count of background presence, said B (t 0 ) The calculation is carried out by adopting a formula C:
B(t 0 )＝B blood vessel (t 0 )×R T/N (formula C)
Wherein B is Blood vessel (t 0 ) For time t 0 Measuring the boron concentration value in ppm in the blood; r is R T/N The ratio of the boron concentration in the tumor to the boron concentration in the normal tissue can be known from PET or experimental data or theoretical basis.
In order to accurately judge which detection devices or monitoring devices are malfunctioning, when the detection values below are greatly different from the standard values, it can be explained that the corresponding detection devices or monitoring devices are malfunctioning.
Tumor dose Rate D at time t T (t) is calculated using formula D:
D T (t)＝D B (t)+D n (t)+D γ (t) (equation D)
Wherein D is T (t) has the unit of w-Gy/s; d (D) B (t) is the boron dose rate at time t in w-Gy/s; d (D) n (t) is the neutron dose rate at time t in w-Gy/s; d (D) γ (t) is the photon dose rate at time t in w-Gy/s, said D B (t) is calculated using equation E:
the D is n (t) is calculated using formula F:
the D is γ (t) is calculated using formula G:
wherein D is B,ref 、D n,ref 、D γ,nbcap,ref And D γ,bcap,ref The unit is w-Gy/s for a given reference value of the boron dose rate or a given reference value of the neutron dose rate through correction, a given reference value of the photon dose rate generated by a non-boron neutron capture reaction and a given reference value of the photon dose rate generated by a boron neutron capture reaction in the treatment planning system respectively; s is S n (t) is a reading of the neutron beam intensity of the neutron monitoring device at time t in counts or selectable readings by the radiation detection device; s is S n,ref For a given value of neutron beam intensity or a given value of neutron beam intensity through correction in a treatment planning system; b (B) Blood vessel (t) is the measured boron concentration value at t in ppm in the blood sample; b (B) Blood, ref For a given value of boron concentration or a given value of boron concentration by correction in ppm in the treatment planning system; f (B) Blood vessel (t),B Blood, ref ) A set of functions pre-computed from the treatment plan to correct for the non-linear relationship between boron concentration and tumor dose.
The beam shaping body includes a reflector, a moderator surrounded by the reflector and adjacent to the neutron generating portion, a thermal neutron absorber adjacent to the moderator, and a radiation shield disposed within the beam shaping body.
Drawings
FIG. 1 is a schematic representation of a boron neutron capture reaction.
FIG. 2 is a schematic diagram of a conventional device 10 B(n,α) 7 And a Li neutron capture nuclear reaction equation.
FIG. 3 is a schematic plan view of a beam diagnostic system for a neutron capture therapy system in an embodiment of the invention.
FIG. 4 is a logical block diagram of the operation of a beam diagnostic system for a neutron capture therapy system in an embodiment of the invention.
Fig. 5 is a schematic plan view of another embodiment of a first neutron beam monitoring device in a beam diagnostic system.
Fig. 6 is a schematic plan view of a radiation detection system for detecting gamma rays emitted instantaneously after irradiation with a neutron beam in a beam diagnostic system.
FIG. 7 is a graph of boron concentration as a function of tumor dose in an example of the invention.
Detailed Description
Neutron capture therapy has been increasingly used in recent years as an effective means of treating cancer, where it is most common to supply neutrons from a boron neutron capture therapy to a nuclear reactor or accelerator. Taking accelerator boron neutron capture therapy as an example, the basic components of accelerator boron neutron capture therapy generally comprise an accelerator for accelerating charged particles (such as protons, deuterons and the like), a target and heat removal system and a beam shaping body, wherein the accelerated charged particles react with a metal target to generate neutrons, and proper nuclear reactions are selected according to the required neutron yield and energy, available energy and current of the accelerated charged particles, physicochemical properties of the metal target and the like, and the nuclear reactions often discussed are 7 Li(p,n) 7 Be and Be 9 Be(p,n) 9 And B, performing an endothermic reaction. The energy threshold values of the two nuclear reactions are respectively 1.881MeV and 2.055MeV, because the ideal neutron source for boron neutron capture treatment is epithermal neutrons with the energy level of keV, in theory, if protons with the energy only slightly higher than the threshold value are used for bombarding a metal lithium target material, relatively low-energy neutrons can Be generated, the nuclear reactions can Be clinically used without too much slowing treatment, however, the proton action cross sections of the two targets of lithium metal (Li) and beryllium metal (Be) and the threshold energy are not high, and in order to generate enough neutron flux, protons with higher energy are generally selected for initiating the nuclear reactions.
The ideal target should have the characteristics of high neutron yield, close neutron energy distribution generated to the epithermal neutron energy region (which will be described in detail later), no too much strong penetrating radiation generation, safety, low cost, easy operation, high temperature resistance, etc., but practically no nuclear reaction meeting all the requirements can be found, and the target is made of lithium metal in the embodiment of the invention. However, it is well known to those skilled in the art that the material of the target may be made of other metallic materials than those mentioned above.
The requirements for the heat removal system are then based onThe nuclear reaction chosen being different, e.g 7 Li(p,n) 7 Be has lower requirements for heat removal systems due to the lower melting point and thermal conductivity of the metal target (lithium metal) 9 Be(p,n) 9 B is high. In the embodiment of the invention adopts 7 Li(p,n) 7 Nuclear reaction of Be.
Whether the neutron source of the boron neutron capture treatment is from nuclear reaction of charged particles of a nuclear reactor or an accelerator and a target, the generated mixed radiation field is that the beam contains neutrons and photons with low energy to high energy; for boron neutron capture treatment of deep tumors, the more radiation content, except for epithermal neutrons, the greater the proportion of non-selective dose deposition of normal tissue, and therefore the less radiation that will cause unnecessary doses. In addition to the air beam quality factor, in order to better understand the dose distribution of neutrons in the human body, the embodiments of the present invention use a human head tissue prosthesis for dose calculation, and use the prosthesis beam quality factor as a design reference for neutron beams, as will be described in detail below.
The international atomic energy organization (IAEA) gives five air beam quality factor suggestions for neutron sources for clinical boron neutron capture treatment, and the five suggestions can be used for comparing the advantages and disadvantages of different neutron sources and serve as reference bases for selecting neutron production paths and designing beam shaping bodies. These five suggestions are as follows:
epithermal neutron beam flux Epithermal neutron flux>1x 10 9 n/cm 2 s
Fast neutron contamination Fast neutron contamination<2x 10 -13 Gy-cm 2 /n
Photon pollution Photon contamination<2x 10 -13 Gy-cm 2 /n
The ratio thermal to epithermal neutron flux ratio of thermal neutron to epithermal neutron flux is less than 0.05
Neutron current to flux ratio epithermal neutron current to flux ratio >0.7
Note that: the epithermal neutron energy region is between 0.5eV and 40keV, the thermal neutron energy region is less than 0.5eV, and the fast neutron energy region is more than 40keV.
1. Epithermal neutron beam flux:
the neutron beam flux and the boron-containing drug concentration in the tumor together determine the clinical treatment time. If the concentration of the boron-containing medicament in the tumor is high enough, the requirement on the neutron beam flux can be reduced; conversely, if the boron-containing drug concentration in the tumor is low, a high flux epithermal neutron is required to administer a sufficient dose to the tumor. IAEA requires a epithermal neutron beam flux of greater than 10 epithermal neutrons per square centimeter per second 9 The neutron beam at this flux can generally control the treatment time to within one hour for current boron-containing drugs, and short treatment times can more effectively utilize the limited residence time of boron-containing drugs within tumors in addition to advantages for patient positioning and comfort.
2. Fast neutron contamination:
since fast neutrons cause unnecessary normal tissue doses, which are positively correlated with neutron energy, as a matter of pollution, the fast neutron content should be minimized in the neutron beam design. Fast neutron contamination is defined as the fast neutron dose accompanied by a unit epithermal neutron flux, with IAEA recommended for fast neutron contamination as less than 2x 10 -13 Gy-cm 2 /n。
3. Photon pollution (gamma ray pollution):
gamma rays belonging to the intense penetrating radiation can cause non-selective dose deposition of all tissues on the beam path, so reducing the gamma ray content is also an essential requirement for neutron beam design, gamma ray pollution is defined as the gamma ray dose accompanied by the unit epithermal neutron flux, and the proposal of IAEA on gamma ray pollution is less than 2x 10 -13 Gy-cm 2 /n。
4. Ratio of thermal neutron to epithermal neutron flux:
because of high thermal neutron attenuation speed and poor penetrating capacity, most of energy is deposited on skin tissues after entering a human body, and thermal neutrons are required to be used as neutron sources for boron neutron capture treatment for superficial tumors such as melanoma and the like, so that the thermal neutron content is required to be reduced for deep tumors such as brain tumors and the like. The IAEA to thermal neutron to epithermal neutron flux ratio is recommended to be less than 0.05.
5. Neutron current to flux ratio:
the ratio of neutron current to flux represents the directionality of the beam, the larger the ratio is, the better the frontage of the neutron beam is, the high frontage neutron beam can reduce the surrounding normal tissue dose caused by neutron divergence, and the treatable depth and the posture setting elasticity are improved. IAEA is recommended to have a neutron current to flux ratio greater than 0.7.
The dose distribution in the tissue is obtained by using the prosthesis, and the quality factor of the prosthesis beam is deduced according to the dose-depth curve of normal tissue and tumor. The following three parameters can be used to make comparisons of the therapeutic benefits of different neutron beams.
1. Effective treatment depth:
the tumor dose is equal to the depth of the maximum dose of normal tissue, and at a position behind the depth, the tumor cells obtain a dose smaller than the maximum dose of normal tissue, i.e. the advantage of boron neutron capture is lost. This parameter represents the penetration capacity of the neutron beam, with a greater effective treatment depth indicating a deeper treatable tumor depth in cm.
2. Effective therapeutic depth dose rate:
i.e. the tumor dose rate at the effective treatment depth, is also equal to the maximum dose rate of normal tissue. Because the total dose received by normal tissues is a factor affecting the total dose size that can be given to a tumor, a larger effective treatment depth dose rate indicates a shorter irradiation time in cGy/mA-min, as the parameters affect the length of treatment time.
3. Effective therapeutic dose ratio:
the average dose ratio received from the brain surface to the effective treatment depth, tumor and normal tissue, is referred to as the effective treatment dose ratio; calculation of the average dose can be obtained from the integration of the dose-depth curve. The larger the effective therapeutic dose ratio, the better the therapeutic benefit of the neutron beam.
In order to make the beam shaping body have a comparative basis in design, besides the five IAEA suggested beam quality factors in air and the three parameters mentioned above, the following parameters for evaluating the neutron beam dose performance are also used in the embodiment of the present invention:
1. the irradiation time is less than or equal to 30min (the proton current used by the accelerator is 10 mA)
2. 30.0RBE-Gy with therapeutic depth of 7cm or more
3. The maximum tumor dose is more than or equal to 60.0RBE-Gy
4. The maximum dose of normal brain tissue is less than or equal to 12.5RBE-Gy
5. The maximum skin dose is less than or equal to 11.0RBE-Gy
Note that: RBE (Relative Biological Effectiveness) is a relative biological effect due to photons and neutrons
The biological effects are different, so the dose terms above are multiplied by the relative biological effects of different tissues, respectively, to find the equivalent dose.
Referring to fig. 3 and 4, in one aspect, the present invention is directed to improving accuracy of a neutron beam irradiation dose of a neutron capture therapy system and providing a beam diagnosis system capable of being used in the neutron capture therapy system for fault diagnosis, and in one aspect, a beam diagnosis system for the neutron capture therapy system is provided.
The neutron capture treatment system includes an accelerator 10, a beam expanding device 20, a charged particle beam inlet for passing a charged particle beam P, a neutron generating section T for generating a neutron beam N by nuclear reaction with the charged particle beam P, a beam shaping body 30 for adjusting the flux and quality of the neutron beam generated by the neutron generating section T, a beam outlet 40 adjacent to the beam shaping body 30, a body to be irradiated 50 irradiated with the beam exiting through the beam outlet 40, and a cooling device 60 for placing a cooling medium at the neutron generating section T to cool the neutron generating section T. The accelerator 10 is used to accelerate the charged particle beam P, and may be a cyclotron or a linear accelerator, which is suitable for an accelerator type neutron capture therapy system; the charged particle beam P here is preferably a proton beam; the beam expander 20 is provided between the accelerator 10 and the neutron generator T; the charged particle beam entrance is housed in the beam shaping body 30 in close proximity to the neutron generator T, and three arrows between the neutron generator T and the beam expander as shown in fig. 3 serve as charged particle beam entrances; the neutron generator T is preferably lithium metal, and is accommodated in the beam shaping body 30; the beam shaping body 30 comprises a reflector 31, a retarder 32 surrounded by the reflector 31 and abutting the neutron generating part T, a thermal neutron absorber 33 abutting the retarder 32, and a radiation shield 34 arranged in the beam shaping body 30, wherein the neutron generating part T and a charged particle beam P incident from a charged particle beam inlet are subjected to nuclear reaction to generate a neutron beam N, the neutron beam defines a main axis, the retarder 32 decelerates neutrons generated by the neutron generating part T to an epithermal neutron energy region, the reflector 31 guides neutrons deviating from the main axis back to the main axis to improve the epithermal neutron beam intensity, the thermal neutron absorber 33 is used for absorbing thermal neutrons to avoid excessive dose caused by shallow normal tissues during treatment, and the radiation shield 34 is used for shielding leaked neutrons and photons to reduce normal tissue dose of a non-irradiated region; the beam outlet 40, which may also be referred to as a neutron beam converging section or collimator, reduces the width of the neutron beam to focus the neutron beam; the neutron beam emitted through the beam outlet 40 irradiates a target site of the body 50 to be irradiated.
The beam diagnosis system comprises a charged particle beam diagnosis device and a neutron beam diagnosis device, and is used for simultaneously diagnosing whether the neutron capture treatment system and/or the beam diagnosis system are in fault. The beam diagnostic system improves the accuracy of the dose irradiated by the neutron beam by detecting both the charged particle beam and the neutron beam. In addition, the beam diagnostic system uses a series of detection results to determine which devices and/or components in the neutron capture therapy system are abnormal, or to determine whether the detection devices themselves in the beam diagnostic system are abnormal. Therefore, the method can achieve the purpose of partial discharge, improves the accuracy of the irradiation dose of the neutron beam, and greatly reduces the maintenance time and the cost.
The charged particle beam diagnostic apparatus further includes a first current detecting means 100 for detecting the intensity and stability of the charged particle beam P before entering the charged particle beam entrance and a second current detecting means 200 for detecting the intensity and variation condition of the charged particle beam P through the interaction with the neutron generating section T; the beam diagnosis system further includes a temperature detection device 300 for detecting the temperature of the cooling device 60 to thereby know the conditions in which the cooling device 60 and the neutron generating section T generate the neutron beam N; the neutron beam diagnostic device further comprises a first neutron beam monitoring device 400 for detecting the intensity variation and the spatial distribution of the neutron beam N in the beam shaping body 30 and embedded in the beam shaping body 30, and a second neutron beam monitoring device 500 for detecting the intensity variation and the spatial distribution of the neutron beam N at the beam outlet 40 and embedded at the beam outlet 40; the beam diagnostic system further comprises a displacement detection means 600 for diagnosing whether the displacement of the object 50 is moving. As one preferred, the first neutron beam monitoring device 400 is provided with two neutron beam monitoring members, namely a first neutron beam monitoring member 401 and a second neutron beam monitoring member 402; the second neutron beam monitoring device 500 is provided with two neutron beam monitoring members, namely a third neutron beam monitoring member 501 and a fourth neutron beam monitoring member 502; the displacement detection device 600 is provided with two displacement detection members, namely a first displacement detection member 601 and a second displacement detection member 602.
Although the first neutron beam monitoring device 400, the second neutron beam monitoring device 500, and the displacement detection device 600 are each provided with two respective monitoring/detection members, the number of these monitoring/detection members may be set as required, for example, 4, 6, or 8, as is well known to those skilled in the art. Such neutron beam monitoring components may be selected so long as they are embedded within (or adjacent to) the beam shaping body and/or within (or adjacent to) the beam outlet to be able to detect the intensity variation and spatial distribution of the neutron beam; such a displacement detecting member may be selected as long as it is disposed in (or adjacent to) the subject to be irradiated and can be used to detect a change in the displacement of the subject to be irradiated. In addition, the positions where these monitoring/detecting members are placed are not strictly limited as long as the placed positions can perform the respective corresponding detecting functions.
The arrangement is such that a wide variety of detection devices are provided from the source of the accelerator up to the terminal of the subject to be irradiated, by which the presence of anomalies in the various critical components of the neutron capture therapy system or in the detection device itself is determined. As a preferred arrangement detection means, from the source of the accelerator up to the terminal of the object to be illuminated: the accelerator comprises a vacuum tube, a neutron generator, a cooling device, a beam shaping body, a beam outlet, a detector and a detector.
In this embodiment, the first current detecting device 100 is a faraday cup (Faraday cup electrometer), which is a cup-shaped metal vacuum detector for measuring the incident intensity and stability of the charged particle beam, and the measured current can be used to determine the number of charged particle beams. When the charged particle beam enters the faraday cup, an electrical current is generated. For a continuous beam of singly charged particles: calculated using equation one, where N is the charged particle number, t is time (in seconds), I is the measured current (in amperes), e is the fundamental charge (about 1.60 x 10 -19 Coulomb). It can be estimated that if the measured current is 10 -9 A (1 nA), i.e. about 60 million charged particles are collected by the faraday cup.
Of course, as is well known to those skilled in the art, the first current detection device 100 may be any detection device suitable for measuring the intensity and stability of the charged particle beam incident at the accelerator vacuum tube, such as a wall current detector (Wall Current Monitor) and a beam transformer (Beam Current Transformer).
The wall current detector is characterized in that a sampling resistor is connected across the two ends of the ceramic isolation section, a voltage sampling signal can be obtained when the beam mirror current flows through the sampling resistor, and the wall current detector is calculated by adopting a formula II, wherein V is a detected voltage value, I b For charged particle beam current, Z can be equivalently a resistance at a specific frequency, and the wall current detector equivalent circuit is a parallel RLC circuit, as in equation three. Thus, according to the detected voltage valueThe current of the charged particle beam over a certain period t is deduced.
V＝-I b (t) Z (formula II)
The beam transformer is a transformer which uses a secondary winding on a magnetic core to couple out a current signal, and the current of the original charged particle beam can be obtained by analyzing the signal. It includes an alternating current transformer (AC Current Transformer, abbreviated ACCT), a fast current transformer (Fast Current Transformer, abbreviated FCT), a resonant current transformer (Tuned Current Transformer, abbreviated TCT), an integrating current transformer (Integrated Current Transformer, abbreviated ICT) and a direct current transformer (DC Current Transformer, abbreviated DCCT). The following description will not be given to beam transformers, but will be given by way of example only, as DCCTs, due to the large variety of transformers. The DCCT adopts a nonlinear magnetic modulation component to modulate a DC signal to be detected to the second harmonic of the excitation signal for detection.
In this embodiment, the second current detecting device 200 is a galvanometer (galvanometer), one end of which is electrically connected to the neutron generating section T, and the other end of which is grounded to form a detection loop, so as to obtain the current on the neutron generating section T during the process of bombarding the neutron generating section T by the charged particle beam P. The galvanometer is made according to the principle that a current-carrying coil is deflected by a moment in a magnetic field. In a common electricity meter, a coil is arranged on a bearing, balance is maintained by a spring hairspring, and deflection is indicated by a pointer. The measured current cannot be too weak due to friction of the bearing. The galvo uses very fine metal suspension wires instead of bearings suspended in a magnetic field, and because the suspension wires are thin and long, the opposing moment is small, so that a very weak current through the coil is sufficient to cause it to deflect significantly. Thus, the galvanometer is much more sensitive than a normal ammeter, and can measure micro-current (10 -7 -10 -10 A) Or micro-voltage (10) -3 -10 - 6 V), such as photocurrent, physiological current, thermoelectromotive force, etc. The first recording of the nerve action potential is achieved with such instruments.
Of course, as is well known to those skilled in the art, the second current detecting device 200 may be any detecting device suitable for detecting the intensity and variation of the charged particle beam that has acted on the neutron generating section in the vicinity of the neutron generating section, such as an ammeter, voltmeter, etc.
In this embodiment, the temperature detecting device 300 is a thermocouple (thermocouple), two conductors (called thermocouple wires or thermodes) with different components are connected together to form a loop, and when the temperatures of the connection points are different, an electromotive force is generated in the loop, which is called a thermoelectric effect, and the electromotive force is called a thermoelectric force. Thermocouples are temperature-measuring using this principle, wherein one end, which is directly used as a measuring medium temperature, is called a working end (also called a measuring end), and the other end is called a cold end (also called a compensating end); the cold end is connected with a display instrument or a matched instrument, and the display instrument can indicate the thermoelectric voltage generated by the thermocouple.
Of course, it is well known to those skilled in the art that the temperature detecting device 300 may be any detecting device, such as a resistance thermometer, which is adapted to be disposed in or adjacent to the cooling device for detecting the temperature of the cooling device to obtain the condition of the neutron beam generated by the cooling device and the neutron generating section, and which uses a temperature sensor made of a material with a known characteristic of resistance varying with temperature to measure the temperature according to the law of the change of the conductor resistance with temperature.
The common neutron beam monitoring device capable of realizing real-time detection has two different detection principles of an ionization chamber and a scintillation detector. Wherein the ionization chamber structure is used as a substrate and is provided with a He-3 proportional counter and BF 3 The ratio counter, the split free chamber and the boron ionization chamber can be divided into organic and inorganic materials, and for the use of detecting thermal neutrons, the scintillation detector is added with high thermal neutron capturing section elements such as Li or B. In short, the neutron energy detected by such detectors is mostly thermal neutrons, and is the charged particles and nuclear fission fragments released by the capturing or nuclear fission reaction of elements and neutrons, a large number of ionization pairs (ion pairs) are generated in an ionization chamber or a scintillation detector head, and after the charges are collected, the charges are properly processedThe current signal can be converted into a voltage pulse signal by the circuit conversion of the circuit. Neutron signals and gamma signals can be easily distinguished by analyzing the magnitude of the voltage pulses. In a high-intensity neutron field, such as BNCT, the gas pressure of an ionization chamber, the concentration of a cleavable material or boron coating or the concentration of a high neutron capture section element in a scintillation detector head can be properly reduced, so that the sensitivity of the scintillation detector to neutrons can be effectively reduced, and the condition of signal saturation is avoided.
More preferably, the first neutron beam monitoring device 400 is a dissociation chamber (dissociation chamber), and when the neutron beam passes through the dissociation chamber, the neutron beam is dissociated with gas molecules inside the dissociation chamber or walls of the dissociation chamber to generate electrons and positively charged ions, which are called ion pairs. Because of the high voltage of the applied electric field in the split free chamber, electrons move toward the central anode wire and positively charged ions move toward the surrounding cathode wall, thus producing a measurable electronic pulse signal. The energy required to generate an ion pair for a gas molecule is called the average free energy, and this value varies depending on the gas species, for example, the average free energy of air is about 34eV. If there is a neutron beam of 340keV, this will cause air to produce about 10k ion pairs.
Of course, as is well known to those skilled in the art, the first neutron beam monitoring device 400 may be any detection device suitable for being embedded in the beam shaping body for detecting the intensity variation and spatial distribution of the neutron beam in the beam shaping body, such as He-3 proportional counter, BF 3 A proportional counter, a boron ionization chamber, a scintillation detection head, etc.
More preferably, the second neutron beam monitoring device 500 is a scintillation detector (scintillator detector) and certain substances emit visible light after absorbing energy, such substances being referred to as scintillating substances. Electrons in crystals or molecules are excited to an excited state by free-radical emission, and fluorescence emitted when the electrons return to a ground state is collected and used for neutron beam monitoring. The visible light emitted by the scintillation detector after acting with the neutron beam can be converted into electrons by utilizing a photomultiplier tube, and the electrons are multiplied and amplified, and the multiplication and amplification rate of the electrons can reach 107 to 108 generally. The number of electrons output by the anode is proportional to the energy of the incoming neutron beam, so that the scintillation detector can measure the energy of the neutron beam.
Of course, as is well known to those skilled in the art, the second neutron beam monitoring device 500 may be any detection device suitable for being placed within or adjacent to the beam outlet for detecting the intensity variation and spatial distribution of the neutron beam at the beam outlet, such as He-3 proportional counter, BF 3 Proportional counter, boron ionization chamber, split free chamber, etc.
More preferably, the displacement detecting device 600 is an infrared detector that operates by detecting infrared rays emitted from a human body. The detector collects external infrared radiation and then gathers the infrared radiation on the infrared sensor. Infrared sensors typically employ pyroelectric elements that release charge outwardly upon receipt of a change in infrared radiation temperature, and an alarm is generated after the detection process. The detector is aimed at detecting human radiation. The radiation-sensitive element must be very sensitive to infrared radiation having a wavelength of around 10 μm.
Of course, as is well known to those skilled in the art, the displacement detection device 600 may be any detection device suitable for detecting a change in displacement of a body to be illuminated, such as a displacement sensor. The displacement sensor determines whether the object to be irradiated moves according to the displacement change of the object to be irradiated relative to a certain reference object. It is also well known to those skilled in the art that the displacement detection device may be used not only to detect a change in displacement of the object to be irradiated, but also to detect a change in displacement of a support member and/or a treatment table, etc. to which the object to be irradiated is fixed, so as to indirectly learn about the change in displacement of the object to be irradiated.
As is well known to those skilled in the art, the number of the first current detecting means, the second current detecting means, the temperature detecting means, the first neutron beam monitoring means, the second neutron beam monitoring means, and the displacement detecting means and the detecting elements are not limited, and the number and the detecting elements in the present embodiment are merely examples.
The components that fail can be clearly enumerated based on the functional relationship of the detection results of the detection and/or monitoring device to each other, and the following are several failure diagnosis conditions based on the corresponding detection results.
When any one of the first current detecting device 100, the second current detecting device 200, the temperature detecting device 300, the first neutron beam monitoring device 400 and the second neutron beam monitoring device 500 is detected to be abnormal, and the other detecting or monitoring devices are normal, the abnormal detecting or monitoring device is deduced to be in fault; when an abnormality is detected in the displacement detection device 600 and other detection or monitoring devices are normal, it is inferred that the displacement of the object 50 is changed or the displacement detection device 600 is malfunctioning.
When it is detected that the first current detecting device 100, the second current detecting device 200, the temperature detecting device 300, the first neutron beam monitoring device 400, and the second neutron beam monitoring device 500 are abnormal, it is inferred that the accelerator 10 is malfunctioning.
When it is detected that the second current detecting device 200, the temperature detecting device 300, the first neutron beam monitoring device 400, and the second neutron beam monitoring device 500 are abnormal and the first current detecting device 100 and the displacement detecting device 600 are normal, it is inferred that the beam expanding device 20 is malfunctioning.
When it is detected that the temperature detection device 300, the first neutron beam monitoring device 400, and the second neutron beam monitoring device 500 are abnormal and the first current detection device 100, the second current detection device 200, and the displacement detection device 600 are normal, it is inferred that the neutron production section T and/or the cooling device 60 are/is malfunctioning.
When it is detected that the first neutron beam monitoring device 400 and the second neutron beam monitoring device 500 are abnormal and the first current detecting device 100, the second current detecting device 200, the temperature detecting device 300 and the displacement detecting device 600 are normal, it is inferred that the beam shaping body 30 is malfunctioning.
When an abnormality of any one of the first neutron beam monitoring means 401 and the second neutron beam monitoring means 402 and/or an abnormality of any one of the third neutron beam monitoring means 501 and the fourth neutron beam monitoring means 502 is detected, it is inferred that the abnormal neutron beam detecting means itself has failed or that uniformity of the neutron beam has been abnormal.
Of course, it is well known to those skilled in the art that the above-described fault diagnosis conditions based on the detection result are just listed as several common cases, and there are many arrangements and combinations, and it is still possible to determine which neutron capture treatment systems or detection devices have faults in themselves in the above manner. Although not listed here, the changes made according to such spirit still belong to the inventive content of the present invention.
The beam diagnostic system includes a control device 700 with a control portion 710, the control portion 710 signaling human perception based on the detection results of the beam diagnostic system to confirm the next operation of the neutron capture therapy system. The human-perceived signal may be a signal that is perceived by a human functional device such as auditory, visual, tactile, or olfactory, such as one or more of an audible alarm, a warning light, vibration, or a pungent odor. As one preferable aspect, the control apparatus 700 further includes a display unit 720, where the display unit 720 is configured to display the detection result of the detection apparatus and/or the fault diagnosis condition based on the detection result on a display device, and the display device may be a common display device such as a television or a liquid crystal display. By feedback from the control device, the operator can easily ascertain the faulty component, and thus the maintenance work of the partial-vector centralised mid-capture treatment system and/or beam diagnostic system.
Referring further to FIG. 5, another embodiment of the first neutron beam monitoring device is shown with the reference numeral 400', wherein like elements are shown with like numerals as those of FIG. 3, and wherein the cooling device and other detection/monitoring devices are omitted for ease of illustration.
The first neutron beam monitoring device 400' may include one or more neutron beam monitoring members, and may be disposed adjacent to the beam shaping body 30 to detect the neutron beam overflowed through the neutron generating section T to directly detect the intensity variation and the spatial distribution of the neutron beam, or disposed adjacent to the beam shaping body 30 to detect the gamma rays generated by the charged particle beam P acting on the neutron generating section T, or indirectly detect the intensity variation and the spatial distribution of the neutron beam according to the functional relationship between the gamma rays and the neutron beam. The control device 700' includes a control section 710' and a display section 720'. The display unit 720 'is configured to display the detection result of the detection device 400' and/or the fault diagnosis condition according to the detection result on a display device, which may be a common display device such as a television or a liquid crystal display. Through feedback from the control device, the operator can easily ascertain the faulty component, so that some of it is directed to the accelerator 10 for the next operation.
Referring further to fig. 6, which is a schematic plan view of a radiation detection system for detecting gamma rays emitted instantaneously after being irradiated by a neutron beam in a beam diagnosis system, a radiation detection device (i.e., a gamma ray detection device emitted instantaneously after being irradiated by a neutron beam) is denoted by numeral 800, the same devices/components as those in fig. 3 are still denoted by the same numerals, and a cooling device and other detection/monitoring devices are omitted for convenience of illustration.
The gamma ray detection device 800 may include one or more gamma ray detection components that are free chambers or scintillation detectors that detect gamma rays. The gamma rays are instantaneous gamma rays after boron neutron capture reaction after neutron beam irradiation. Knowing the gamma count of the measured preset energy interval (0.48 MeV generated during the boron neutron capture reaction, for example only), the boron concentration value can be deduced from the functional relationship between gamma rays and boron concentration. The control device 700 "includes a control unit 710" and a display unit 720". The display unit 720″ is configured to display the detection result of the detection device 800 and/or the fault diagnosis condition based on the detection result on a display device, which may be a common display device such as a television or a liquid crystal display. Through feedback from the control device, the operator can easily ascertain the faulty component, so that some of it is directed to the accelerator 10 for the next operation.
The term "gamma rays which are instantaneously emitted after being irradiated with a neutron beam" means gamma rays generated when a neutron beam is reacted with other elements, such as elements which are known in the art to generate gamma rays when a neutron capturing nuclear reaction occurs, but other elements are not limited to boron-10 elements. In the embodiment of the invention, the 'gamma rays instantaneously emitted after the neutron beam irradiates' are gamma rays generated when the neutron beam and the boron-10 element generate boron neutron capture reaction.
Preferably, the boron concentration value is calculated using formula a:
wherein B (t) is the boron concentration value at time t in ppm, time t in s, k is the measured value, and GC (t) is the gamma count of the detected preset energy interval minus the gamma count of the background at time t; the k is calculated by adopting a formula B:
wherein B (t) 0 ) For time t 0 Boron concentration in ppm, time t 0 Is in units of s, GC (t 0 ) For time t 0 When a gamma count of a preset energy interval minus a gamma count of the background presence is detected, said B (t 0 ) The calculation is carried out by adopting a formula C:
B(t 0 )＝B blood vessel (t 0 )×R T/N (formula C)
Wherein B is Blood vessel (t 0 ) For time t 0 Measuring the boron concentration value in ppm in the blood; r is R T/N The ratio of the boron concentration in the tumor to the boron concentration in the normal tissue can be known from PET or experimental data or theoretical basis.
In order to accurately judge which detection devices or monitoring devices are malfunctioning, when the detection values below are greatly different from the standard values, it can be explained that the corresponding detection devices or monitoring devices are malfunctioning.
Tumor dose Rate D at time t T (t) is calculated using formula D:
D T (t)＝D B (t)+D n (t)+D γ (t) (equation D)
Wherein D is T (t) has the unit of w-Gy/s; d (D) B (t) is the boron dose rate at time t in w-Gy/s; d (D) n (t) is the neutron dose rate at time t in w-Gy/s; d (D) γ (t) is the photon dose rate at time t in w-Gy/s, said D B (t) is calculated using equation E:
the D is n (t) is calculated using formula F:
the D is γ (t) is calculated using formula G:
wherein D is B,ref 、D n,ref 、D γ,nbcap,ref And D γ,bcap,ref The unit is w-Gy/s for a given reference value of the boron dose rate or a given reference value of the neutron dose rate through correction, a given reference value of the photon dose rate generated by a non-boron neutron capture reaction and a given reference value of the photon dose rate generated by a boron neutron capture reaction in the treatment planning system respectively; s is S n (t) is a reading of the neutron beam intensity of the neutron monitoring device at time t in counts or selectable readings by the radiation detection device; s is S n,ref For a given value of neutron beam intensity or a given value of neutron beam intensity through correction in a treatment planning system; b (B) Blood vessel (t) is the measured boron concentration value at t in ppm in the blood sample; b (B) Blood, ref For a given value of boron concentration or by correction of boron concentration in a treatment planning systemIn ppm; f (B) Blood vessel (t),B Blood, ref ) A set of functions pre-computed from the treatment plan to correct for the non-linear relationship between boron concentration and tumor dose.
Preferably, the tumor dose rate at time t can also be calculated from the following formula H:
wherein S is B (t) is the reading of the radiation detection device at time t in counts or alternatively by the radiation detection device, S B (t) is calculated from the following formula I; c is a calculated value calculated from formula J:
wherein N is NB,ref A reference value for the number of boron neutron capture reactions occurring in the treatment plan; k (k) BG Is the correction of the background; sigma is the detection efficiency of the radiation detection device; s is S n (t 0 ) For time t 0 The neutron beam intensity of the neutron monitoring device is read in counts or alternatively by the radiation detection device; b (B) Blood vessel (t 0 ) For measuring at t in the blood sample 0 Boron concentration in ppm; f (B) Blood vessel (t 0 ),B Blood, ref ) Correcting a nonlinear relationship between boron concentration and tumor dose for a set of functions pre-calculated from a treatment plan; s is S B (t 0 ) The reading of the radiation detection device, which is set at the initial stage of irradiation, is given in counts or alternatively by the radiation detection device.
As shown in FIG. 7, which shows the boron concentration B in the present embodiment Blood vessel (t) and tumor dose B Tumor(s) (t) a graph of the functional relationship between (c) and (d). Preferably, the neutron source intensity is 1.7X10 11 On the basis of n/s, the nonlinear relation between the boron concentration and the tumor dose is calculated by adopting the following formula K, so that the nonlinear relation between the boron concentration and the tumor dose can be effectively corrected in the neutron capture treatment system, and the accuracy of the treatment plan is improved.
B Tumor(s) (t)＝0.01643+0.8034×B Blood vessel (t)-0.00167×B Blood vessel (t) 2 -2.42362×10 -5 ×B Blood vessel (t) 3
(formula K)
As is well known to those skilled in the art, the boron concentration B shown in FIG. 7 Blood vessel (t) and tumor dose B Tumor(s) The functional relationship between (t) is not limited to the manner of expression K, and the boron concentration B is formulated based on empirical values Blood vessel (t) and tumor dose B Tumor(s) And (t) a nonlinear functional relationship between the two. Boron concentration B shown in FIG. 7 Blood vessel (t) and tumor dose B Tumor(s) The functional relationship between (t) is also not limited to a neutron source intensity of 1.7X10 11 n/s, it is empirically possible to derive different functional relationships based on different neutron source intensities. The neutron capture treatment system in the embodiment of the invention can correct the nonlinear function relation between the boron concentration and the tumor dosage so as to improve the accuracy of the treatment plan.
The neutron monitoring device and the radiation detection device should correct for hysteresis effects.
Another aspect of the embodiments of the present invention is to provide a radiation detection method for a neutron capture therapy system, which improves accuracy of a neutron beam irradiation dose of the neutron capture therapy system and can find a fault portion in time, and the radiation detection method corresponds to the radiation detection system.
In summary, the first neutron beam monitoring device may be disposed in the beam shaping body or adjacent to the beam shaping body, and a detection device that can detect the change in the intensity and the spatial distribution of the neutron beam in the beam shaping body at the disposed position may be used.
The radiation detection system for neutron capture therapy systems and the corresponding radiation detection method of the present invention are not limited to the structures described in the above embodiments and shown in the drawings. Obvious changes, substitutions, or modifications to the materials, shapes, and positions of the components therein are made on the basis of the present invention, and are within the scope of the present invention as claimed.
Claims (3)
1. A neutron capture therapy system, characterized by: the neutron capture treatment system comprises a charged particle beam, a charged particle beam inlet for passing the charged particle beam, a neutron generating part for generating a neutron beam through nuclear reaction with the charged particle beam, a beam shaping body for adjusting the flux and quality of the neutron beam generated by the neutron generating part, and a beam outlet adjacent to the beam shaping body, wherein the neutron capture treatment system corrects the nonlinear relation between the boron concentration and the tumor dose;
the neutron capture treatment system also comprises a radiation detection system, wherein the radiation detection system comprises a radiation detection device, the radiation detection device is used for detecting gamma rays instantaneously emitted after being irradiated by a neutron beam, and the gamma rays instantaneously emitted after being irradiated by the neutron beam are gamma rays generated when the neutron beam and boron-10 element undergo a boron neutron capture reaction;
wherein, the boron concentration value is calculated by adopting a formula A:
wherein B (t) is the boron concentration value at time t in ppm, time t in s, k is the measured value, and GC (t) is the gamma count of the detected preset energy interval minus the gamma count of the background at time t; the k is calculated by adopting a formula B:
Wherein B (t) 0 ) For time t 0 Boron concentration in ppm, time t 0 Is in units of s, GC (t 0 ) For time t 0 When a gamma count of a preset energy interval minus a gamma count of the background presence is detected, said B (t 0 ) The calculation is carried out by adopting a formula C:
B(t 0 )＝B blood vessel (t 0 )×R T/N (formula C)
Wherein B is Blood vessel (t 0 ) For time t 0 Measuring the boron concentration value in ppm in the blood; r is R T/N The ratio of the boron concentration in the tumor to the boron concentration in the normal tissue can be known according to PET or experimental data or theoretical basis;
tumor dose Rate D at time t T (t) is calculated using formula D:
D T (t)＝D B (t)+D n (t)+D γ (t) (equation D)
Wherein D is T (t) has the unit of w-Gy/s; d (D) B (t) is the boron dose rate at time t in w-Gy/s; d (D) n (t) is the neutron dose rate at time t in w-Gy/s; d (D) γ (t) is the photon dose rate at time t in w-Gy/s, said D B (t) is calculated using equation E:
the D is n (t) is calculated using formula F:
the D is γ (t) is calculated using formula G:
wherein D is B,ref 、D n,ref 、D γ,nbcap,ref And D γ,bcap,ref The unit is w-Gy/s for a given reference value of the boron dose rate or a given reference value of the neutron dose rate through correction, a given reference value of the photon dose rate generated by a non-boron neutron capture reaction and a given reference value of the photon dose rate generated by a boron neutron capture reaction in the treatment planning system respectively; s is S n (t) is a reading of the neutron beam intensity of the neutron monitoring device at time t in counts or selectable readings by the radiation detection device; s is S n,ref For a given value of neutron beam intensity or a given value of neutron beam intensity through correction in a treatment planning system; b (B) Blood vessel (t) is the measured boron concentration value at t in ppm in the blood sample; b (B) Blood, ref For a given value of boron concentration or a given value of boron concentration by correction in ppm in the treatment planning system; f (B) Blood vessel (t),B Blood, ref ) A set of functions pre-computed from the treatment plan to correct for the non-linear relationship between boron concentration and tumor dose.
2. The neutron capture therapy system of claim 1, wherein: the radiation detection system also comprises an accelerator and a control device, wherein the accelerator is used for accelerating the charged particle beam, and the control device sends out a human perception signal according to the detection result of the radiation detection device so as to confirm the next operation of the neutron capture treatment system; the control device includes a control section and a display section, the control section displaying a detection result of the radiation detection system through the display section and feeding back the detection result to the accelerator to confirm a next operation of the accelerator.
3. The neutron capture therapy system of claim 1, wherein: the radiation detection device is a free chamber or a scintillation detector for detecting gamma rays.
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| CN106730372B (en) * | 2016-12-31 | 2023-06-27 | 广东恒聚医疗科技有限公司 | Positioning system for radiotherapy |
| JP7175964B2 (en) * | 2017-08-24 | 2022-11-21 | 南京中硼▲聯▼康医▲療▼科技有限公司 | Neutron capture therapy system |
| CN109464749B (en) * | 2017-09-07 | 2024-02-23 | 南京中硼联康医疗科技有限公司 | Neutron capture therapy system |
| RU2745081C1 (en) | 2017-09-07 | 2021-03-19 | Нойборон Медтех Лтд. | Neutron capture therapy system |
| CN108051847B (en) * | 2017-12-05 | 2019-10-29 | 清华大学 | Utilize the method and neutron dose rate instrument of lanthanum bromide detector measurement neutron dose rate |
| CN108121005B (en) * | 2017-12-05 | 2019-09-17 | 清华大学 | Utilize the method and neutron dose rate instrument of bromination cerium detector measurement neutron dose rate |
| JP6947934B2 (en) | 2017-12-18 | 2021-10-13 | 南京中硼▲聯▼康医▲療▼科技有限公司Ｎｅｕｂｏｒｏｎ Ｍｅｄｔｅｃｈ Ｌｔｄ． | Neutron capture therapy system |
| CN109925612A (en) * | 2017-12-18 | 2019-06-25 | 南京中硼联康医疗科技有限公司 | Neutron capture treatment system |
| CN109085193A (en) * | 2018-09-04 | 2018-12-25 | 东莞东阳光高能医疗设备有限公司 | A kind of the proton application system and its operating method of automatic quickly detection boron concentration |
| CN109173081B (en) * | 2018-09-10 | 2020-12-22 | 东莞东阳光高能医疗设备有限公司 | Beam evaluation method, device and equipment for boron neutron capture therapy and storage medium |
| CN112546454A (en) * | 2019-09-25 | 2021-03-26 | 中硼(厦门)医疗器械有限公司 | Neutron capture treatment equipment and use method of irradiation parameter selection device |
| CN113877078B (en) * | 2020-07-03 | 2023-06-02 | 中硼(厦门)医疗器械有限公司 | Neutron dose detection device and neutron capture treatment equipment |
| CN114534117B (en) * | 2020-11-25 | 2023-09-01 | 中硼(厦门)医疗器械有限公司 | Neutron capture therapy device |
| CN112618970B (en) * | 2021-01-06 | 2022-03-15 | 南京航空航天大学 | Device and medium for boron neutron capture treatment biological dose calculation method |
| TWI828268B (en) * | 2022-08-11 | 2024-01-01 | 禾榮科技股份有限公司 | Dose control system |
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