Neutron capture therapy equipment

Abstract

The present invention provides a neutron capture therapy device, which comprises a neutron beam irradiation system, a monitoring system and an anti-error operation system. The neutron beam irradiation system is used to generate a neutron beam, the monitoring system is used to control the entire neutron beam irradiation process, and the anti-error operation system is used to prevent erroneous instructions and information from being input into the monitoring system.

Description

Technical Field

[0001] The invention relates to the field of radioactive ray irradiation, and in particular to a neutron capture therapy device. Background Art

[0002] With the development of atomic science, radiation therapy such as cobalt-60, linear accelerator, and electron beam has become one of the main means of cancer treatment. However, 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. In addition, due to the different sensitivity of tumor cells to radiation, traditional radiotherapy is often not effective in treating malignant tumors that are more resistant to radiation (such as glioblastoma multiforme and melanoma).

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

[0004] During the boron neutron capture therapy, the radiation dose to the patient needs to be precisely controlled because the neutron beam used for radiation therapy is strong. However, when formulating the treatment plan, there are still problems such as inaccurate settings of preset irradiation parameters, such as neutron irradiation dose, and inaccurate detection of actual irradiation dose.

[0005] In addition, during the actual irradiation process, due to errors by operators or doctors, accidentally touching the control panel may lead to incorrect input of instructions or changes in related instructions and irradiation parameters, which increases medical risks. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a neutron capture therapy device capable of delivering an accurate neutron irradiation dose to a patient, comprising a neutron beam irradiation system, a monitoring system and an anti-error operation system, wherein the neutron beam irradiation system is used to generate a neutron beam, the monitoring system is used to control the neutron beam irradiation process, and the anti-error operation system is used to prevent erroneous instructions and information from being input into the monitoring system.

[0007] Furthermore, the error-proof operation system includes a secondary confirmation unit, which is used to transmit a signal to the monitoring system that all information has been confirmed to be correct. Before the secondary confirmation unit is activated, the neutron capture therapy device cannot be started for neutron beam irradiation.

[0008] Furthermore, the error-proof operation system includes an anti-mistake part, and the monitoring system includes an input part for inputting and modifying irradiation parameters and control instructions. During the activation of the anti-mistake part, the input part is locked.

[0009] Furthermore, it also includes a report generation button, and during the activation of the fool-proofing unit, the report generation button is locked.

[0010] Furthermore, the secondary confirmation unit is a confirmation information correct button for confirming that the information input from the input unit is correct.

[0011] Furthermore, the fool-proof part is an irradiation start button for starting the neutron capture therapy device to perform neutron beam irradiation.

[0012] Furthermore, it also includes an irradiation pause button. After activating the irradiation pause button, the start irradiation button can be directly activated again to implement neutron beam irradiation with the original irradiation parameters and instructions.

[0013] Furthermore, it also includes a cancel irradiation button. After activating the cancel irradiation button, all irradiation parameters are cleared. When implementing neutron beam irradiation again, it is necessary to re-enter the irradiation parameters and activate the confirmation information correct button and the start irradiation button in sequence.

[0014] Furthermore, the monitoring system also includes a storage unit for storing irradiation parameters, a control unit for executing a treatment plan according to the irradiation parameters stored in the storage unit, and a display unit for displaying the remaining irradiation time or the remaining irradiation time and at least part of the irradiation parameters in real time.

[0015] Furthermore, it also includes a detection system for detecting irradiation parameters during neutron beam irradiation therapy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of a neutron beam irradiation system of a neutron capture therapy device of the present invention;

[0017] Figure 2 is a schematic diagram of a beam shaping body of a neutron capture therapy device of the present invention;

[0018] Figure 3 is a schematic diagram of a neutron beam irradiation system and a detection system of a neutron capture therapy device of the present invention;

[0019] Figure 4is a schematic diagram of a neutron dose detection device of a first embodiment of a neutron capture therapy device of the present invention;

[0020] Figure 5 is a schematic diagram of a neutron dose detection device of a second embodiment of a neutron capture therapy device of the present invention;

[0021] Figure 6 Schematic diagram of the monitoring system of the neutron capture therapy device of the present invention

[0022] Figure 7 It is a schematic diagram of the anti-misoperation system of the neutron capture therapy device of the present invention combined with a display unit and an input unit. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and technical effect of the present invention more clear and understandable, and enable those skilled in the art to implement them accordingly, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0024] In the following description, the terms "first", "second", etc. may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the objects being described and do not have any order or technical meaning.

[0025] Radiation therapy is a common method of treating cancer. Boron neutron capture therapy has been increasingly used as an effective method of treating cancer in recent years. Figures 1 to 7 As shown, a neutron capture therapy device for irradiating a body to be irradiated, such as a patient S, with a neutron beam of a preset neutron dose for boron neutron capture therapy (BNCT) comprises a neutron beam irradiation system 1, a detection system, a monitoring system 3, a correction system and an anti-misoperation system. The neutron beam irradiation system 1 is used to generate a neutron beam suitable for neutron irradiation therapy for the patient S, the detection system is used to detect irradiation parameters such as neutron dose during the neutron beam irradiation therapy, the monitoring system 3 is used to control the entire neutron beam irradiation process, the correction system is used to correct the preset neutron dose, and the anti-misoperation system is used to prevent relevant personnel from inputting wrong instructions and information into the monitoring system 3.

[0026] Boron neutron capture therapy is the use of boron ( 10 B) The drug has a high capture cross section for thermal neutrons. 10 B(n,α) 7 Li neutron capture and nuclear fission reaction production 4 He and 7Li has two heavily charged particles, and the average energy of the two heavily charged particles is about 2.33MeV, with high linear energy transfer (Linear Energy Transfer, LET) and short range characteristics. 4 The linear energy transfer and range of He particles are 150keV / μm and 8μm respectively. 7 The linear energy transfer and range of the Li heavy-charged particles are 175keV / μm and 5μm respectively. The total range of the two heavy-charged particles is approximately equivalent to the size of a cell, so the radiation damage to the organism can be limited to the cellular level. Boron-containing drugs selectively accumulate in tumor cells. After the neutron beam enters the patient S's body, it undergoes a nuclear reaction with the boron in the patient S's body to produce 4 He and 7 Li two heavily charged particles, 4 He and 7 The two heavily charged particles of Li kill tumor cells locally without causing too much damage to normal tissues.

[0027] Reference Figure 1 As shown, the neutron beam irradiation system 1 includes a neutron beam generating module 11 and a beam adjusting module 12 for adjusting the neutron beam generated by the neutron beam generating module 11 .

[0028] The neutron beam generation module 11 generates a neutron beam to irradiate the patient S, and includes an accelerator 111 for accelerating a charged particle beam, a target 112 that reacts with the charged particle beam to generate a neutron beam, and a charged particle beam transmission unit 113 located between the accelerator 111 and the target 112 for transmitting the charged particle beam. The charged particle beam transmission unit 113 transmits the charged particle beam to the target 112, and one end of the charged particle beam transmission unit 113 is connected to the accelerator 111 and the other end is connected to the target 112. In addition, beam control devices such as a beam adjustment unit (not shown) and a charged particle scanning unit (not shown) are provided on the charged particle beam transmission unit 113. The beam adjustment unit controls the traveling direction and beam diameter of the charged particle beam. The charged particle beam scanning unit scans the charged particle beam and controls the irradiation position of the charged particle beam relative to the target 112.

[0029] The accelerator 111 may be a cyclotron, a synchrotron, a synchrocyclotron or a linear accelerator. Common targets 112 include lithium (Li) targets and beryllium (Be) targets. The charged particle beam is accelerated to an energy sufficient to overcome the Coulomb repulsion of the atomic nuclei of the target 112 and to generate a charge. 7 Li(p,n) 7 Be nuclear reactions to produce neutron beams. Commonly discussed nuclear reactions include 7 Li(p,n) 7 Be and 9 Be(p,n) 9B. Generally, the target 112 includes a target layer and an anti-oxidation layer located on one side of the target layer for preventing oxidation of the target layer, wherein the anti-oxidation layer is made of Al or stainless steel.

[0030] In the embodiment disclosed in the present invention, an accelerator 111 is used to accelerate charged particles and generate nuclear reactions with the target 112 to supply the neutron source. In other embodiments, a nuclear reactor, a DT neutron generator, a DD neutron generator, etc. may be used to supply the neutron source. However, whether the neutron source is supplied by accelerating charged particles and generating nuclear reactions with the target 112 as disclosed in the present invention, or by using a nuclear reactor, a DT neutron generator, a DD neutron generator, etc. to supply the neutron source, a mixed radiation field is generated, that is, the generated beam includes a high-speed neutron beam, an epithermal neutron beam, a thermal neutron beam, and a gamma ray. In the process of boron neutron capture therapy, in addition to epithermal neutrons, the more the content of the remaining radiation (collectively referred to as radiation pollution) is, the greater the proportion of non-selective dose deposition in normal tissues is, so these radiations that will cause unnecessary dose deposition should be reduced as much as possible.

[0031] The International Atomic Energy Agency (IAEA) has given five recommendations for air beam quality factors for neutron sources used in clinical boron neutron capture therapy. These five recommendations can be used to compare the advantages and disadvantages of different neutron sources and serve as a reference for selecting neutron production methods and designing beam shapers 121. The five recommendations are as follows:

[0032] Epithermal neutron flux>1x 10 9 n / cm 2 s

[0033] Fast neutron contamination <2x 10 -13 Gy-cm 2 / n

[0034] Photon contamination<2x 10 -13 Gy-cm 2 / n

[0035] Thermal to epithermal neutron flux ratio <0.05

[0036] Epithermal neutron current to flux ratio>0.7

[0037] Note: The epithermal 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.

[0038] Combination Figure 2 and Figure 3 As shown, the beam adjustment module 12 is used to adjust the mixed radiation generated by the neutron beam generation module 11, so that the radiation contamination finally irradiated to the patient S is minimized and the epithermal neutrons used to treat the patient S are focused to the part of the patient S that needs to be irradiated. The beam adjustment module 12 includes a beam shaping body 121 for decelerating and shielding the neutron beam and a collimator 122 for focusing the epithermal neutrons to the part of the patient S that needs to be irradiated. Specifically, the beam shaping body 121 includes a retarder 1211 that can decelerate the neutron beam generated from the target 112 to the epithermal neutron energy zone, a reflector 1212 that guides the deviated neutrons back to the retarder 1211 to increase the beam intensity of the epithermal neutrons, a thermal neutron absorber 1213 for absorbing thermal neutrons to avoid excessive dose deposition in shallow normal tissues during treatment, and a radiation shield 1214 for shielding leaked neutrons and photons to reduce the dose deposition of normal tissues in non-irradiated areas. In other embodiments, the thermal neutron absorber may not be included, and the thermal neutrons may be absorbed by the material contained in the retarder or the reflector, or the retarder and the thermal neutron absorber may be integrated. In other embodiments, the radiation shield may not be included, and the material may be the same as the reflector, or the reflector and the radiation shield may be integrated.

[0039] The retarder 1211 can be formed by stacking a plurality of different materials. The material of the retarder 1211 is selected according to factors such as the energy of the charged particle beam. For example, when the energy of the proton beam from the accelerator 111 is 30 MeV and a beryllium target is used, the material of the retarder 1211 is lead, iron, aluminum or calcium fluoride; when the energy of the proton beam from the accelerator 111 is 11 MeV and a beryllium target is used, the material of the retarder 1211 is heavy water (D2O) or lead fluoride, etc. As a preferred embodiment, the retarder 1211 is made of a mixture of MgF2 and LiF accounting for 4.6% by weight of MgF2, the reflector 1212 is made of Pb, and the thermal neutron absorber 1213 is made of 6 The radiation shield 1214 includes a photon shield and a neutron shield, wherein the photon shield is made of lead (Pb) and the neutron shield is made of polyethylene (PE). The shape of the retarder 1211 can be Figure 2 The revealed biconical shape can also be Figure 3 The disclosed cylindrical reflector 1212 is arranged around the retarder 1211, and its shape is adaptively changed according to the shape of the retarder 1211.

[0040] Continue to refer to Figure 3As shown, the detection system includes a neutron dose detection device 21 for detecting the neutron dose of the neutron beam in real time, a temperature detection device 22 for detecting the temperature of the target 112, a displacement detection device 23 for detecting whether the patient S is displaced during the treatment process, and a boron concentration detection device (not shown) for detecting the boron concentration in the patient S.

[0041] Combination Figure 4 As shown, the neutron dose detection device 21 includes a detector 211 for receiving neutrons and outputting signals, a signal processing unit 212 for processing the signal output from the detector 211, a counter 213 for counting the signal output from the signal processing unit 212 to obtain a count rate, a conversion unit 214 for converting the count rate recorded by the counter 213 into a neutron flux rate or a neutron dose rate, an integration unit 215 for integrating the neutron flux rate or the neutron dose rate to obtain a neutron dose, and a display 218 for displaying the neutron dose. The detector 211, the signal processing unit 212, and the counter 213 form a count rate channel 20.

[0042] The detector 211 may be placed in the beam shaper 121 , in the collimator 122 , or at any position adjacent to the beam shaper 121 , as long as the position of the detector 211 can be used to detect the neutron dose of the neutron beam.

[0043] The detector 211 capable of detecting the neutron dose of the neutron beam in real time includes an ionization chamber and a scintillation detector head. Among them, the ionization chamber structure is used as the base material for the He-3 proportional counter, the BF3 proportional counter, the fission ionization chamber, and the boron ionization chamber. The scintillation detector head contains organic materials or inorganic materials. When detecting thermal neutrons, the scintillation detector head often adds high thermal neutron capture cross-section elements such as Li or B. An element in the two types of detectors captures or undergoes nuclear fission reactions with the neutrons entering the detector to release heavily charged particles and nuclear fission fragments, generating a large number of ionization pairs in the ionization chamber or the scintillation detector head. These charges are collected and form electrical signals, which are subjected to noise reduction, conversion, and separation processing by the signal processing unit 212, and the electrical signals are converted into pulse signals. By analyzing the size of the voltage pulse, the neutron pulse signal and the gamma pulse signal are distinguished. The separated neutron pulse signal is continuously recorded by the counter 213 to obtain the neutron counting rate (n / s). The conversion unit 214 calculates and converts the count rate through internal software, programs, etc. to obtain the neutron flux rate (cm -2 s -1 ), the neutron dose rate (Gy / s) is obtained by further calculation and conversion of the neutron flux rate. Finally, the integration part integrates the neutron dose rate to obtain the real-time neutron dose.

[0044] The following is a brief introduction using the fission chamber, scintillator detector and BF3 detector as examples.

[0045] When the neutron beam passes through the fission ionization chamber, it interacts with the gas molecules inside the fission ionization chamber or the wall of the fission ionization chamber to generate electrons and positively charged ions, which are called the above-mentioned ion pairs. Due to the external electric field high voltage in the fission ionization chamber, the electrons move toward the central anode wire and the positively charged ions move toward the surrounding cathode walls, thus generating a measurable electrical signal.

[0046] The optical fiber and other materials in the scintillation detector absorb energy and generate visible light. It uses ionizing radiation to excite the electrons in the crystal or molecule to an excited state. When the electrons return to the ground state, the fluorescence emitted is collected and used as neutron beam detection. The visible light emitted by the scintillation detector after the interaction with the neutron beam is converted into an electrical signal output using a photomultiplier tube.

[0047] The BF3 detector is placed in the beam shaper 121 to receive neutron beam irradiation. The B element in the BF3 detector undergoes nuclear reaction with the neutrons. 10 B(n,alpha) 7 Li, alpha particles produced by nuclear reactions and 7 Li charged particles are collected by high-voltage electrodes under the drive of voltage, generating electrical signals. The electrical signals are transmitted to the signal processing unit 212 through a coaxial cable for signal amplification and filtering and shaping to form a pulse signal. The processed pulse signal is transmitted to the counter 213 for pulse counting to obtain the counting rate (n / s), and the neutron beam intensity, i.e., the neutron dose, can be measured in real time through the counting rate.

[0048] The temperature detection device 22 is a thermocouple. Two conductors of different components (called thermocouple wires or hot electrodes) are connected at both ends to form a loop. When the temperatures of the junctions are different, an electromotive force will be generated in the loop. This phenomenon is called the thermoelectric effect, and this electromotive force is called the thermoelectric potential. Thermocouples use this principle to measure temperature. The end that is directly used to measure the temperature of the medium is called the working end (also called the measuring end), and the other end is called the cold end (also called the compensation end); the cold end is connected to a display instrument or a matching instrument, and the display instrument will indicate the thermoelectric potential generated by the thermocouple. Of course, it is well known to those skilled in the art that the temperature detection device 22 can also be any detector 211 that can detect temperature, such as a resistance thermometer.

[0049] The displacement detection device 23 is an infrared signal detector, which works by detecting infrared rays emitted by the human body. The infrared detector collects infrared radiation from the outside and then gathers it on the infrared sensor. The infrared sensor usually uses a pyroelectric element. When the temperature of this element changes after receiving infrared radiation, it will release electric charge to the outside, and generate an alarm after detection and processing. This detector 211 is aimed at detecting human body radiation. Therefore, the radiation sensitive element must be very sensitive to infrared radiation with a wavelength of about 10μm. Of course, it is well known to those skilled in the art that the displacement detection device 23 can be any detection device suitable for detecting the displacement change of the object to be illuminated, such as a displacement sensor. The so-called displacement sensor determines whether the object to be illuminated moves based on the displacement change of the object to be illuminated relative to a certain reference object. It is also well known to those skilled in the art that the displacement detection device 23 can be used not only to detect the displacement change of the object to be illuminated, but also to detect the displacement change of the support and / or treatment table that fixes the object to be illuminated, thereby indirectly knowing the displacement change of the object to be illuminated.

[0050] During the neutron beam irradiation treatment of the patient S, boron is continuously supplied to the patient S when necessary. The detection of boron concentration can be achieved by inductively coupled plasma spectroscopy, high-resolution α radioautography, charged ion spectroscopy, neutron capture camera, nuclear magnetic resonance and magnetic resonance imaging, positron emission tomography, prompt gamma-ray spectrometer, etc. The device involved in the above detection method is called a boron concentration detection device.

[0051] The present invention is described by taking the example of calculating the boron concentration in the patient S by detecting the gamma rays released by the patient S. After the neutron beam enters the patient's body and reacts with the boron to generate gamma rays, the amount of boron reacting with the neutron beam can be calculated by measuring the amount of gamma rays, thereby calculating the boron concentration in the patient S. The boron concentration detection device is used to measure the boron concentration in the patient S in real time during the process of the neutron beam irradiation system 1 performing neutron beam irradiation treatment on the patient S.

[0052] The boron concentration detection device detects the gamma rays (478kev) generated by the reaction of neutrons and boron to measure the boron concentration, and a boron distribution measurement system (PG (Prompt-γ)-SPECT) that can measure the boron concentration distribution by measuring single-energy gamma rays is used as the boron concentration detection device. The boron concentration detection device has a gamma-ray detection unit and a boron concentration calculation unit. The gamma-ray detection unit is used to detect information related to the gamma rays emitted from the body of the patient S, and the boron concentration calculation unit calculates the boron concentration in the body of the patient S based on the information related to the gamma rays detected by the gamma-ray detection unit. The gamma-ray detection unit can use a scintillator and various other gamma-ray detection equipment. In the present embodiment, the gamma-ray detection unit is arranged near the tumor of the patient S, for example, at a position about 30 cm away from the tumor of the patient S.

[0053] The detector 211 of the neutron dose detection device 21 for detecting the neutron dose of the neutron beam is a pulse detector, and the shortest time interval between two consecutive incident neutrons that can be distinguished by the detector 211 is defined as the pulse resolution time τ(s). Within the τ time after a neutron is incident on the detector 211, the detector 211 cannot accurately record other incident neutrons, so it is also called dead time.

[0054] The sensitivity of the detector 211 in detecting neutrons is the ratio of the total output of the detector 211 to the corresponding total input. For the detector 211 of the neutron dose detection device 21 exemplified in the present invention, the input physical quantity is a neutron beam, and the output physical quantity is generally an optical signal or an electrical signal. The higher the ratio of the total output to the corresponding total input, the higher the sensitivity of the detector 211 in detecting neutrons. The higher the sensitivity in detecting neutrons, the smaller the corresponding pulse resolution time τ of the detector 211. In order to reduce statistical errors, usually, a low-flux beam is detected by a detector 211 with a high sensitivity in detecting neutrons, and a high-flux beam is detected by a detector 211 with a low sensitivity in detecting neutrons.

[0055] Different embodiments are described in detail below. For simplicity, the same components are identified by the same numbers in different embodiments, and similar components are identified by the same numbers plus "'" or "" in different embodiments to distinguish them.

[0056] exist Figure 4 In the first embodiment disclosed, the neutron dose detection device 21 has only one count rate channel 20. In order to accurately detect the neutron dose of neutron beams with different fluxes, Figure 5 In the disclosed embodiment 2, the neutron dose detection device 21' includes at least two count rate channels 20', and the detector 211' of each count rate channel 20' has different sensitivities for detecting neutrons. Furthermore, the neutron dose detection device 21' also includes a count rate channel selection unit 216 for selecting a suitable count rate channel 20' according to the current power of the accelerator 111 or the neutron beam flux. Specifically, in the embodiment 2, the neutron dose detection device 21' includes at least two count rate channels 20', a count rate channel selection unit 216 for selecting a suitable count rate channel 20' from the at least two count rate channels 20', a conversion unit 214 for converting the count rate recorded by the count rate channel 20' selected by the count rate channel selection unit 216 into a neutron flux rate or a neutron dose rate, and an integration unit 215 for integrating the neutron flux rate or the neutron dose rate to obtain a neutron dose.

[0057] The two count rate channels 20' are named as the first count rate channel 201 and the second count rate channel 202 respectively. The first count rate channel 201 includes a first detector 2011 for receiving neutrons and outputting signals, a first signal processing unit 2012 for processing the signals output from the first detector 2011, and a first counter 2013 for counting the signals output from the first signal processing unit 2012; the second count rate channel 202 includes a second detector 2021 for receiving neutrons and outputting signals, a second signal processing unit 2022 for processing the signals output from the second detector 2021, and a second counter 2023 for counting the signals output from the second signal processing unit 2022. The count rate channel selection unit 216 selects a suitable count rate channel 20 according to the current power of the accelerator 111 or the neutron beam flux, the conversion unit 214 converts the count rate recorded by the count rate channel 20 selected by the count rate channel selection unit 216 into a neutron flux rate or a neutron dose rate, and the integration unit 215 integrates the neutron flux rate or the neutron dose rate to obtain the neutron dose.

[0058] Generally, the neutron flux that can be generated when the accelerator 111 is at maximum power is defined as the maximum neutron flux. When the detected real-time neutron flux is less than half of the maximum neutron flux, the neutron flux is considered to be small; when the detected real-time neutron flux is greater than or equal to half of the maximum neutron flux, the neutron flux is considered to be large.

[0059] The sensitivity of the first detector 2011 for detecting neutrons is the first sensitivity, and the sensitivity of the second detector 2021 for detecting neutrons is the second sensitivity, and the first sensitivity is less than the second sensitivity. Specifically, the first detector 2011 is wrapped with a large amount of neutron absorbing materials, such as B4C, Cd, or filled with low-pressure working gas or designed to be smaller in size, thereby reducing the sensitivity of detecting neutrons. When the neutron flux is large, the first detector 2011 is used for detection, which can reduce the counting rate loss caused by the pulse resolution time. Compared with the first detector 2011, the second detector 2021 is wrapped with a small amount of neutron absorbing materials or is not wrapped with any materials or filled with high-pressure working gas or designed to be large in size. Therefore, the second sensitivity is greater than the first sensitivity. When the neutron flux is small, the second detector 2021 is used for detection, which can reduce the counting rate statistical error caused by the low counting rate.

[0060] Correspondingly, the sensitivity of the first count rate channel 201 for detecting neutrons is less than the sensitivity of the second count rate channel 202 for detecting neutrons. The count rate selection unit selects a suitable count rate channel 20' according to the current power or neutron flux of the accelerator 111. For example, when the maximum beam current intensity of the accelerator 111 is 10 mA, when the beam current intensity of the accelerator 111 is greater than 5 mA, the count rate recorded by the first counter 2013 of the first count rate channel 201 with the first sensitivity is selected to be transmitted to the conversion unit 214 for dose calculation; when the beam current intensity of the accelerator 111 is less than 5 mA, the count rate recorded by the second counter 2023 of the second count rate channel 202 with the second sensitivity is selected to be transmitted to the conversion unit 214 for dose calculation. The count rate selection unit selects a relatively accurate count rate and transmits it to the conversion unit 214 for dose calculation, thereby obtaining an accurate neutron irradiation dose.

[0061] The neutron dose detection device 21 is provided with at least two first counting rate channels 201 and second counting rate channels 202 with different sensitivities for detecting neutrons. The counting rate channel selection unit 216 selects a more accurate counting rate for calculating the neutron dose according to actual conditions, thereby avoiding the counting rate loss error caused by the pulse resolution time, while taking into account the statistical error caused by the low counting rate, thereby improving the accuracy of real-time neutron dose detection, and further improving the accuracy of the neutron dose of the neutron beam irradiated to the patient S.

[0062] In other embodiments, the count rate channels 20, 20' can be set to any number as needed.

[0063] In addition, in the embodiments listed above, the count rate channel 20 is selected based on the power of the accelerator 111, the neutron flux, etc. In other embodiments, the count rate channel 20' can be selected based on the distance between the detector 211 and the neutron source. For example, when the detector 211 is set at a position close to the neutron source, the second count rate channel 202 with the second sensitivity is selected; when the detector 211 is set at a position far away from the neutron source, the first count rate channel 201 of the detector with the first sensitivity is selected.

[0064] The detector 211 of the above-mentioned neutron dose detection device 21 is a pulse detector. Generally, pulse detectors have the problem of time resolution. The incident neutron reacts with the detector 211 to generate a signal pulse, which will be followed by a τ time interval. All other signal pulses generated during this time interval will be regarded as the same signal pulse by the detector 211. In this case, as long as the time interval between any two signal pulses is less than τ, the second pulse will not be recorded. Therefore, the count rate recorded by the counter 213 has a deviation and needs to be corrected. The conversion unit 214 converts the count rate C according to the corrected count rate. kCombined with the dose conversion factor, the real-time and accurate neutron flux rate and neutron dose rate D are obtained. t (Gy / s).

[0065] Recombination Figure 4 and Figure 5 As shown, further, the neutron dose detection device 21 also includes a counting rate correction unit 217 for correcting the counting rate, and the counting rate correction unit 217 includes a counting rate correction calculation unit, a counting rate correction factor calculation unit and a pulse resolution time calculation unit.

[0066] The counting rate correction calculation unit uses formula (1-1) to calculate the corrected counting rate C k :

[0067] C k =K·C t (1-1)

[0068] K is the counting rate correction factor;

[0069] C t It is the real-time counting rate recorded by the counter 213.

[0070] The counting rate correction factor calculation unit uses formula (1-2) to calculate the counting rate correction factor K:

[0071]

[0072] n is the number of pulses recorded by the counter 213 per unit time, that is, the real-time counting rate per unit time (n / s);

[0073] m is the number of signal pulses actually generated in the detector 211 per unit time, that is, the number of neutrons reacting with the detector 211 per unit time (n / s).

[0074] When the number of neutrons entering the detector 211 and reacting in a unit time is m, and the number of pulses actually recorded by the counter 213 in a unit time is n, the time for the counter tube to fail to work is nτ, and the total number of neutrons entering the counter tube and unable to be recorded during this time is mnτ, that is, the lost count is: mn, and formula (1-3) is obtained by deduction:

[0075] nm=nmτ (1-3)

[0076] Substituting formula (1-3) into formula (1-2), we get formula (1-4):

[0077]

[0078] It can be seen from the above formula that knowing the pulse resolution time τ can be combined with the number of pulses recorded by counter 213 and formula (1-4) to calculate the count rate correction factor, and the count rate correction factor can be substituted into formula (1-1) to calculate the corrected count rate.

[0079] Conventional pulse resolution time calculation methods include dual source method and reactor power method, both of which require two natural neutron sources or reactors for calculation, which are costly. The embodiment of the present invention calculates the pulse resolution time based on the monitoring system of the neutron capture therapy device, making full use of existing equipment and resources to reduce costs.

[0080] Specifically, the accelerator 111 is first operated in a low flux state. At this time, the neutron beam flux is the first neutron beam flux I1. At this time, the count rate recorded by the counter 213 is C1. Since it is in a low flux state, theoretically, the detector 211 will not be affected by the pulse resolution time and there will be signal pulses that are not recorded. Then the accelerator 111 is operated to a high flux state. At this time, the neutron beam flux is the second neutron beam flux I2. At this time, the count rate recorded by the counter 213 is C2. At this time, the count rate is affected by the pulse resolution time so that some signal pulses are not recorded. The pulse resolution time calculation unit calculates the pulse resolution time τ according to formula (1-5):

[0081]

[0082] If the position of the detector 211 does not change, the pulse resolution time does not need to be calculated every time the device is running. However, after the detector 211 has been working for a long time, the performance parameters will change, causing the pulse resolution time to change, so the pulse resolution time needs to be calculated periodically.

[0083] The count rate correction unit 217 can calculate the pulse resolution time of the detector 211, and can calculate the count rate correction factor based on the pulse resolution time, so as to correct the count rate error caused by the pulse resolution time, further improve the accuracy of real-time neutron dose detection, and further improve the accuracy of the neutron dose of the neutron beam irradiated to the patient S.

[0084] Before the irradiation treatment is performed, the total neutron dose to be delivered to the patient S, the neutron flux rate or neutron dose rate or current during the irradiation, the required irradiation time, the irradiation angle and other irradiation parameters are obtained by simulation, calculation and the like. For the sake of convenience, the above parameters are collectively referred to as preset irradiation parameters. In other embodiments, some of the above parameters or more parameters not mentioned can be understood as preset irradiation parameters, which are respectively referred to as preset neutron dose (Gy), preset neutron flux rate (cm -2 s -1 ), preset neutron dose rate (Gy s -1), preset current (A) and preset irradiation time (s), etc. During the irradiation process, due to changes in certain factors, it is necessary to periodically adjust the irradiation parameters according to the relevant parameters detected by the detection system. The irradiation parameters detected by the detection system are named real-time irradiation parameters, and the adjusted irradiation parameters are named modified irradiation parameters. The adjusted irradiation parameters may be preset irradiation parameters or modified irradiation parameters.

[0085] Reference Figure 6 As shown, the monitoring system 3 includes an input unit 31 for inputting preset irradiation parameters, a storage unit 32 for storing irradiation parameters, a control unit 33 for executing a treatment plan according to the irradiation parameters stored in the storage unit 32, a reading unit 34 for reading real-time irradiation parameters detected by the detection system, a calculation unit 35 for performing operations on the real-time irradiation parameters stored in the storage unit 32 and the preset irradiation parameters / corrected irradiation parameters, a judgment unit 36 ​​for judging whether it is necessary to correct the irradiation parameters according to the calculation results of the calculation unit 35, a correction unit 37 for correcting part of the irradiation parameters in the storage unit 32 when the judgment unit 36 ​​determines that the irradiation parameters need to be corrected, and a display unit 38 for displaying the remaining irradiation time or the remaining irradiation time and other irradiation parameters in real time.

[0086] Before the preset irradiation parameters are corrected, the irradiation parameters stored in the storage unit 32 are preset irradiation parameters; the irradiation parameters corrected by the correction unit 37 are also preset irradiation parameters; the remaining irradiation time displayed by the display unit 38 is the difference between the preset irradiation time and the real-time irradiation time, and the irradiation parameters displayed by the display unit 38 are preset irradiation parameters. After the preset irradiation parameters are corrected, the irradiation parameters stored in the storage unit 32 are corrected irradiation parameters; the irradiation parameters corrected again by the correction unit 37 are also corrected irradiation parameters; the remaining irradiation time displayed by the display unit 38 is the corrected remaining irradiation time, and the irradiation parameters displayed by the display unit 38 are corrected irradiation parameters. Of course, the preset irradiation parameters and the corrected irradiation parameters can also be displayed at the same time.

[0087] In other embodiments, the input unit 31 , the storage unit 32 , etc. may not be included.

[0088] The monitoring system 3 is electrically connected to the detection system, so the relevant information detected by the detection system can be transmitted to the monitoring system 3. The display 218 of the neutron dose detection device 21 in the detection system and the display unit 38 of the monitoring system 3 can be the same device, usually a display screen.

[0089] The operation process of monitoring system 3 refers to Figure 6 The specific description is as follows:

[0090] S1: The input unit 31 inputs preset irradiation parameters, such as preset neutron flux rate or preset neutron dose rate or preset current, preset neutron dose and preset irradiation time, preset boron concentration and other preset irradiation parameters;

[0091] S2: The storage unit 32 stores the irradiation parameters;

[0092] S3: The control unit 33 executes the treatment plan according to the irradiation parameters stored in the storage unit 32;

[0093] S4: The reading unit 34 reads the real-time irradiation parameters detected by the detection system;

[0094] S5: the calculation unit 35 calculates the irradiation parameters stored in the storage unit 32 and the real-time irradiation parameters read by the reading unit 34;

[0095] S6: the judging unit 36 ​​judges whether it is necessary to correct the irradiation parameters stored in the storage unit according to the calculation result of the calculating unit 35;

[0096] S7: When the determination unit 36 ​​determines that the irradiation parameters stored in the storage unit 32 need to be corrected, the correction unit 37 corrects the latest irradiation parameters in the storage unit 32;

[0097] When the determination unit 36 ​​determines that the irradiation parameters stored in the storage unit 32 do not need to be corrected, the correction unit 37 does not perform the correction action;

[0098] S8: The display unit 38 displays the remaining irradiation time or the remaining irradiation time and other irradiation parameters in real time based on the irradiation parameters stored in the storage unit 32.

[0099] During the operation of the monitoring system 3, the reading unit 34 periodically reads the real-time irradiation parameters, for example, reads the real-time irradiation parameters once every 5 minutes, and transmits them to the calculation unit 35 for relevant operations. When the calculation unit 35 obtains that the difference between the real-time irradiation parameters and the preset irradiation parameters is greater than the first threshold value or the real-time irradiation parameters are greater than the second threshold value or less than the third threshold value, the judgment unit 36 ​​gives an instruction to correct the irradiation parameters. Next, the correction unit 37 corrects the irradiation parameters stored in the storage unit 32; otherwise, the judgment unit 36 ​​gives an instruction that the irradiation parameters do not need to be corrected. At this time, the correction unit 37 will not correct the irradiation parameters stored in the storage unit 32. For example: when the difference between the neutron dose rate obtained by calculation by the calculation unit 35 and the preset neutron dose rate, or the real-time neutron flux rate and the preset neutron flux rate, or the real-time boron concentration and the preset boron concentration, or the corrected remaining irradiation time and the remaining irradiation time (the difference between the preset irradiation time and the actually implemented irradiation time, or the remaining irradiation time of the last correction) is greater than the first threshold, or the real-time neutron dose rate, real-time neutron flux rate or real-time boron concentration obtained by comparison by the calculation unit 35 is greater than the second threshold or less than the third threshold.

[0100] Before the preset irradiation parameters are corrected, the storage unit 32 stores the preset irradiation parameters, and the display unit 38 displays the remaining irradiation time and other preset irradiation parameters in real time. After the preset irradiation parameters are corrected, the storage unit 32 stores the latest set of corrected irradiation parameters, and the display unit 38 displays the corrected remaining irradiation time and the latest set of other corrected irradiation parameters in real time. In addition to the remaining irradiation time, the display unit 38 specifically displays which irradiation parameters can be selected according to actual needs. All irradiation parameters can be displayed, or some irradiation parameters can be displayed. Usually, the display unit 38 displays information such as the remaining irradiation time, real-time irradiation dose, and boron concentration.

[0101] In the embodiment disclosed in the present invention, the calculation unit 35 combines the real-time neutron dose Dr detected by the neutron dose detection device 21 and the preset neutron dose D input from the input unit 31. total , the corrected remaining irradiation time t is obtained by calculation r , where t0 is the preset irradiation time, t is the real-time irradiation time detected by the detection system, i.e., the implemented irradiation time, is the average neutron dose value in the time period t, P is the percentage of the real-time neutron dose to the preset neutron dose, and P is calculated using formula (2-1):

[0102]

[0103] When P is less than 97%, use formula (2-2) and formula (2-3) to calculate the corrected remaining irradiation time t r :

[0104]

[0105]

[0106] At this time, the correction unit 37 only needs to correct the preset irradiation time or the corrected remaining irradiation time stored in the storage unit 32 .

[0107] When P is greater than or equal to 97%, the correction unit 37 adjusts the neutron dose rate to a first neutron dose rate that is less than the preset neutron dose rate and increases the irradiation time accordingly to prevent the patient S from absorbing too many neutrons. The first neutron dose rate is 1 / 7 to 1 / 2 of the preset neutron dose rate. Preferably, the neutron dose rate is adjusted to the preset neutron dose rate I d 1 / 5 of the first neutron dose rate, that is, the first neutron dose rate is equal to I d / 5, use formula (2-4) to calculate the corrected remaining irradiation time t r :

[0108]

[0109] At this time, the correction unit 37 needs to modify the remaining irradiation time and the preset neutron dose rate in the storage unit 32 to the corrected remaining irradiation time t r and the corrected neutron dose rate, the control unit 33 executes the treatment plan according to the corrected irradiation parameters. In other embodiments, the neutron dose rate may be adjusted to other multiples such as 1 / 3, 1 / 4, 1 / 6 or 1 / 7 of the preset neutron dose rate to prevent the patient S from absorbing too many neutrons under the irradiation of the neutron beam with a high neutron dose rate; in addition, the correction unit 37 may adjust the neutron dose rate when P is greater than or equal to 90%, greater than or equal to 95% or greater than or equal to other ratios, and the specific ratio may be preset according to actual conditions; of course, it is also possible not to judge whether the neutron dose rate needs to be adjusted to a first neutron dose rate less than the preset neutron dose rate based on the value of P calculated by the calculation unit 35, but after the condition that the percentage of the preset neutron dose, the real-time neutron dose and the preset neutron dose reaches a certain value and the neutron dose needs to be corrected, a threshold is manually set and input into the storage unit 32 through the input unit 31 for storage, and when the detected real-time neutron dose is greater than or equal to the threshold, the judgment unit 36 ​​determines that the irradiation parameters need to be corrected, and starts the correction unit 37 to adjust the neutron dose rate to the first neutron dose rate less than the preset neutron dose rate.

[0110] In the above embodiment, when P is less than 97%, the calculation unit 35 calculates the irradiation time required to complete the irradiation of the preset neutron dose under the premise of keeping the real-time neutron dose rate unchanged. In other embodiments, the irradiation time can be kept unchanged, and the neutron dose rate or boron concentration can be changed to achieve the purpose of completing the irradiation of the preset dose within the preset irradiation time. The method of changing the neutron dose rate includes changing the power of the accelerator, changing the thickness of the target layer of the target 112, etc. The corrected neutron dose rate Ir is calculated using formula (2-5):

[0111]

[0112] Since the neutron dose rate is obtained by calculating the neutron flux rate through the conversion factor, and the neutron flux rate is obtained by integrating the neutron count rate, the corrected neutron dose rate is equivalent to the corrected neutron flux rate and the neutron count rate.

[0113] In this embodiment, when P is greater than or equal to 97%, in order to prevent the patient S from absorbing too many neutrons under the irradiation of the neutron beam with a high neutron dose rate, the neutron dose rate is still adjusted to 1 / 5 of the preset neutron dose rate and the corrected remaining irradiation time t is calculated using formula (2-4): r .

[0114] When the irradiation time actually implemented reaches the preset irradiation time or the neutron dose actually irradiated reaches the preset neutron dose, the control unit sends an instruction to stop irradiation to the neutron capture therapy device.

[0115] The monitoring system 3 is provided with a correction unit 37 to correct the irradiation parameters for executing the treatment plan stored in the storage unit 32, so as to ensure that the neutron dose of the neutron beam irradiated to the patient S is basically consistent with the preset neutron dose, and further improve the accuracy of the neutron dose of the neutron beam irradiated to the patient S; in addition, when the percentage of the real-time neutron dose to the preset neutron dose is greater than or equal to 97%, the neutron dose rate is lowered and the irradiation time is increased accordingly to prevent the patient S from absorbing too many neutrons under the irradiation of the neutron beam with a high neutron dose rate, which also has the effect of improving the accuracy of the neutron dose of the neutron beam irradiated to the patient S.

[0116] In the above-listed embodiments, it is determined whether the preset irradiation parameters need to be corrected based on the real-time neutron dose obtained from the neutron dose detection device 21, and the corrected irradiation parameters are calculated based on the real-time irradiation parameters and the preset irradiation parameters. In other embodiments, it is determined whether the preset parameters need to be corrected based on the real-time irradiation parameters detected by the temperature detection device 22, the displacement detection device 23 or the boron concentration detection device, and the corrected irradiation parameters are calculated based on the real-time irradiation parameters detected by these detection devices. For example: when the boron concentration detection device detects that the boron concentration in the patient S is inconsistent with the preset boron concentration or does not fall within the preset interval, the correction unit 37 corrects the irradiation time or corrects the rate of boron delivery to the patient. Usually, when the irradiation treatment is nearing the end, it is difficult to correct the boron concentration in the patient S in a short period of time. At this time, it is usually chosen to correct the irradiation time.

[0117] The accuracy of the neutron beam irradiation dose is crucial in practical treatment. Too much irradiation dose will cause potential harm to patient S, while too little irradiation dose will reduce the quality of treatment. The calculation error in the calculation link of the preset neutron dose and the deviation between the real-time irradiation parameters and the preset irradiation parameters during the actual irradiation process will cause inaccurate neutron irradiation dose. Therefore, in the actual irradiation process, in addition to real-time correction of irradiation parameters, the calculation of preset irradiation parameters is also crucial. Therefore, a correction system is required to correct the preset neutron dose to ensure that the neutron irradiation dose administered to patient S is more accurate. When correcting the preset neutron dose of the neutron beam, it is necessary to consider the influence of factors such as patient S's positioning deviation, real-time neutron dose rate deviation, boron concentration in the patient's body, and neutron flux.

[0118] The correction coefficients used in the correction system include the neutron correction coefficient K1 and the boron correction coefficient K2. p and the neutron beam intensity correction factor Ki Related; boron correction factor K2 and boron concentration correction factor K b and the boron self-shielding effect correction factor K s related.

[0119] The deviation between the real-time neutron dose rate and the preset neutron dose rate will directly lead to the deviation of the final neutron dose irradiated to the patient. Therefore, the positioning correction factor K is introduced. p and the neutron beam intensity correction factor K i Correction for neutron irradiation dose.

[0120] The so-called self-shielding effect means that when the boron concentration is different, the track of the neutron beam entering the tumor is also different. Specifically, the higher the boron concentration in the body of patient S, the worse the penetration ability of the neutron beam, then the shorter the track of the neutron beam entering the tumor, and the neutron beam reacts with boron in a shallower track. Conversely, the longer the track of the neutron beam entering the tumor, the neutron beam reacts with boron in a deeper track. Specifically, the first boron concentration value in the patient's body is obtained by the boron concentration detection device, the neutron beam enters the tumor with a first track, and the correction system obtains the first boron correction coefficient; the second boron concentration value in the patient's body is obtained by the boron concentration detection device, the neutron beam enters the tumor with a second track, and the correction system obtains the second boron correction coefficient; wherein, the first boron concentration value is higher than the second boron concentration value, the first track is smaller than the second track, and the first boron correction coefficient is smaller than the second boron correction coefficient. Therefore, when calculating the neutron irradiation dose, it is necessary to consider the influence of the self-shielding effect on the actual irradiation effect and irradiation track of the neutron beam, so the boron concentration correction coefficient K is introduced. b and the boron self-shielding effect correction factor K s Correction for neutron irradiation dose.

[0121] Specifically, the neutron correction coefficient K1 and the positioning correction coefficient K are calculated using formula (3-1), formula (3-2) and formula (3-3) respectively. p and the neutron beam intensity correction factor K i , the relevant formula is as follows:

[0122] K1=K p ·K i (3-1)

[0123]

[0124]

[0125] Wherein, D is the actual treatment dose, i.e., the real-time neutron dose D measured by the neutron dose detection device 21. r ;

[0126] D0 is the uncorrected preset neutron dose;

[0127] I is the intensity of the actual neutron beam, which is the real-time neutron dose rate measured by the neutron dose detection device 21;

[0128] I0 is the theoretical beam intensity, that is, the preset neutron dose rate input from the input unit 31 .

[0129] The boron correction coefficient K2 and the boron concentration correction coefficient K are calculated using formula (3-4), formula (3-5) and formula (3-6) respectively. b and the boron self-shielding effect correction factor K s , the relevant formula is as follows:

[0130] K2=K b ·K S (3-4)

[0131]

[0132]

[0133] Wherein, B is the actual boron concentration in the patient S, that is, the real-time boron concentration detected by the boron concentration detection device;

[0134] B0 is the boron concentration setting value in the treatment plan, that is, the preset boron concentration input from the input unit 31;

[0135] is the thermal neutron flux in the patient S when the boron concentration distribution is B;

[0136] is the thermal neutron flux in the patient S when the boron concentration distribution is B0.

[0137] The uncorrected preset neutron dose D0 is calculated using the following formula (3-7):

[0138] D eq =D B ·B con ·CBE+D f ·RBE n +D th ·RBE n +D r ·RBE r (3-7)

[0139] The preset neutron dose D in the corrected treatment plan total Use the following formula (3-8) for calculation:

[0140] D total =K1·(K2·D B ·Bcon ·CBE+D f ·RBE n +D th ·RBE n +D r ·RBE r ) (3-8)

[0141] Among them, D B The dose at 1 ppm boron concentration, unit: Gy;

[0142] B con is the actual measured boron concentration, unit: ppm;

[0143] D f is the fast neutron dose, unit: Gy;

[0144] D th is the thermal neutron dose, unit: Gy;

[0145] RBE n is the relative biological effect of neutrons;

[0146] D r is the gamma dose, unit: Gy;

[0147] RBE r is the relative biological effect of gamma.

[0148] During actual treatment, the correction system corrects the preset neutron dose in the pre-established treatment plan to prevent the patient S from receiving an inaccurate neutron dose.

[0149] The correction system comprehensively considers the influence of factors such as the positioning deviation of patient S, the real-time neutron dose rate deviation, and the real-time boron concentration on the preset neutron dose, and introduces the neutron correction coefficient K1 and the boron correction coefficient K2 to correct the preset neutron dose, thereby ensuring the accuracy of the neutron dose of the neutron beam irradiating patient S at the source.

[0150] During actual treatment, after the input unit 31 completes the input of the preset irradiation parameters, the operator starts the neutron capture therapy device for irradiation treatment. After the irradiation starts, the input function of the input unit 31 is locked, and the relevant irradiation parameters can no longer be re-entered. Although this can prevent the wrong parameters and instructions from being input by accidental touch or misoperation during the irradiation process, when the treatment process is slightly inconsistent with the ideal state, the irradiation can only be stopped or continued in an abnormal state. The parameters cannot be corrected or the instructions cannot be changed in time during the irradiation process. However, if the operation interface is simply set to be able to be controlled in real time, after the irradiation starts, the irradiation parameters and control instructions can still be input through the input unit 31. Although this can ensure that the correct irradiation parameters and instructions are input in real time during the irradiation process, there is a risk that the irradiation process will input wrong parameters, instructions or repeatedly input operation instructions due to misoperation, thereby affecting the irradiation results.

[0151] Reference Figure 7 As shown, the neutron capture therapy device has a control interface, which is composed of the above-mentioned input unit 31, display unit 38, confirmation information correct button 51, start irradiation button 52, pause irradiation button 53, cancel irradiation button 54 and generate report button 55. The operator activates the confirmation information correct button 51 to transmit a signal that all information has been confirmed to be correct to the monitoring system 3. Only after the monitoring system 3 receives the signal that all information is confirmed to be correct, the necessary conditions for starting the neutron capture therapy device for neutron beam irradiation are met. After the monitoring system 3 receives the signal that all information is confirmed to be correct, the start irradiation button 52 is activated again, and the sufficient conditions for starting the neutron capture therapy device for neutron beam irradiation are met. After the neutron capture therapy device is started, the neutron beam irradiation can be paused by the pause irradiation button 53, and the neutron beam irradiation can be canceled by the cancel irradiation button 54. After the irradiation is completed, activating the generate report button 55 can automatically generate a report related to the irradiation therapy. Pausing neutron beam irradiation means keeping all irradiation parameters and instructions unchanged. Neutron beam irradiation is implemented with the original irradiation parameters and instructions by activating the start irradiation button 52 again. Canceling neutron beam irradiation means clearing all irradiation parameters and instructions. When implementing neutron beam irradiation again, it is necessary to re-enter the irradiation parameters and instructions, and activate the confirmation information correct button 51 and the start irradiation button 52 in sequence.

[0152] The error-proof operation system comprehensively considers the factors of operability and safety, and sets a secondary confirmation unit and a fool-proof unit to ensure safe and accurate irradiation, while ensuring that the system does not lack real-time operability. Before the operator activates the secondary confirmation unit to transmit a signal to the neutron capture therapy device that all information has been confirmed to be correct, the neutron capture therapy device cannot start to execute the irradiation treatment plan, that is, the start irradiation button 52 cannot be activated. During the activation of the fool-proof unit, the input unit 31 that can modify and input irradiation parameters and instructions and the generate report button 55 are locked.

[0153] In the embodiment disclosed by the present invention, the secondary confirmation part is a confirmation information correct button 51 on the control interface. Before the doctor starts the program to execute the treatment plan, the relevant information needs to be confirmed twice. After the operator confirms that the input is correct and inputs the confirmed information correct instruction to the monitoring system 3 by clicking the confirmation information correct button 51, the device can be started to execute the treatment plan, thereby reducing the risk of erroneous input of erroneous control instructions introduced due to misoperation. For example, before the doctor performs irradiation treatment on the patient S, the doctor needs to verify the patient information (such as name, gender, age, etc.) and irradiation parameters (such as irradiation dose, collimator number), etc. After verifying that all the information is correct, the confirmation information correct button 51 on the control interface needs to be clicked to start the irradiation function. Otherwise, even if the doctor clicks the start irradiation button 52, the device refuses to start neutron beam irradiation and gives a prompt that the information is not confirmed.

[0154] In the embodiment disclosed by the present invention, the foolproof part is the start irradiation button 52. When the irradiation button 52 is activated to start the treatment plan, the input function of the input part 31 is locked and no information can be input. Specifically, before the irradiation treatment is performed, the relevant instructions and irradiation parameters are input through the input part 31. After the relevant irradiation parameters and instructions are input into the monitoring system 3, the operator checks whether the relevant irradiation parameters and instructions are correct. After confirming that they are correct, the operator activates the confirmation information correct button 51. After that, the input part 31 will be locked and the relevant irradiation parameters and instructions can no longer be modified or added through the input part 31, so as to prevent erroneous input. The relevant irradiation parameters and instructions can only be input again after the input part 31 is unlocked. In the embodiment disclosed by the present application, after clicking the pause irradiation button 53 or the cancel irradiation button 54, the irradiation treatment stops. At the same time, the input part 31 for inputting relevant information is unlocked. At this time, the relevant information can be modified and added through the input part 31. Of course, after the irradiation treatment is completed, the input part will be automatically unlocked. In this way, erroneous input is prevented and the operability of the system can be guaranteed. For example, after the medical staff verifies that the patient S information, irradiation parameters and other information are correct, they click the confirm information correct button 51 on the control interface, and then click the start irradiation button 52. Subsequently, the system starts irradiation treatment. At this time, the input unit 31 used to input relevant information is locked and information input cannot be implemented.

[0155] Before the irradiation treatment is completed, the generate report button 55 is also locked. Only after the irradiation treatment is completed, the generate report button 55 will be automatically unlocked, that is, the generate treatment report function can be turned on.

[0156] The fool-proofing part is not limited to the start irradiation button 52 in the above example, but is also applicable to other important buttons and parameter input windows; and the implementation carrier of secondary confirmation and key fool-proofing can be software or hardware. For example, the fool-proofing part can also be a key or a dip switch on the control panel. Before the key or the switch is turned on, certain operations cannot be performed. Only when the key is turned on or the switch is turned on can the relevant operations be executed.

[0157] In the embodiment disclosed in the present invention, the input of instructions and irradiation parameters is performed by means of a touch screen. In other embodiments, keys (such as mechanical keys) may be used for input.

[0158] The anti-error operation system can not only ensure the parameter setting and control command input function when necessary, but also reduce the wrong input parameters or repeated input commands due to wrong operation or other reasons, thereby reducing the risk of equipment operation.

[0159] The neutron dose detection device 21 of the neutron capture therapy device of the present invention is provided with at least two first counting rate channels 201 and second counting rate channels 202 with different sensitivities for detecting neutrons and a counting rate channel selection unit 216. The counting rate channel selection unit 216 selects a relatively accurate counting rate for calculating the neutron dose according to actual conditions, which can avoid the counting rate loss error caused by the pulse resolution time, while taking into account the statistical error caused by the low counting rate, thereby improving the accuracy of real-time neutron dose detection, and further improving the accuracy of the neutron dose of the neutron beam irradiated to the patient S; in addition, the neutron dose detection device 21 is also provided with a counting rate correction unit 217 to calculate the pulse resolution time of the detector 211, and can calculate the counting rate correction factor according to the pulse resolution time, thereby correcting the counting rate error caused by the pulse resolution time, further improving the accuracy of real-time neutron dose detection, and further improving the accuracy of the neutron dose of the neutron beam irradiated to the patient S.

[0160] The neutron capture therapy device of the present invention also has a monitoring system 3, and the monitoring system 3 is provided with a correction unit 37 to periodically correct the irradiation parameters stored in the storage unit 32 for executing the treatment plan, so as to ensure that the neutron dose of the neutron beam irradiated to the patient S is basically consistent with the preset neutron dose, thereby further improving the accuracy of the neutron dose of the neutron beam irradiated to the patient S; in addition, when the percentage of the real-time neutron dose to the preset neutron dose is greater than or equal to 97%, the neutron dose rate is lowered and the irradiation time is increased accordingly to prevent the patient S from absorbing too many neutrons under the irradiation of the neutron beam with a high neutron dose rate, which also has the effect of improving the accuracy of the neutron dose of the neutron beam irradiated to the patient S.

[0161] The neutron capture therapy device of the present invention also has a correction system, which comprehensively considers the influence of factors such as the positioning deviation of the patient S, the real-time neutron dose rate deviation, and the real-time boron concentration on the preset neutron dose, and introduces the neutron correction coefficient K1 and the boron correction coefficient K2 to correct the preset neutron dose, thereby ensuring the accuracy of the neutron dose of the neutron beam irradiating the patient S at the source.

[0162] In summary, the neutron capture therapy device of the present invention can deliver accurate neutron beam irradiation doses to patients and reduce the equipment operation risks caused by misoperation while ensuring the operability of the equipment.

[0163] The neutron capture therapy device disclosed in the present invention is not limited to the contents described in the above embodiments and the structures shown in the drawings. Any obvious changes, substitutions or modifications made to the materials, shapes and positions of the components thereof based on the present invention are within the scope of protection claimed by the present invention.

Claims

1. A neutron capture therapy device, characterized in that: The system comprises a neutron beam irradiation system, a monitoring system and an anti-misoperation system, wherein the neutron beam irradiation system is used to generate a neutron beam, the monitoring system is used to control the process of neutron beam irradiation, and the anti-misoperation system is used to prevent the input of erroneous instructions and information into the monitoring system; and further comprises a detection system for detecting irradiation parameters during neutron beam irradiation therapy; The monitoring system includes an input unit for inputting preset irradiation parameters, a judgment unit for judging whether the irradiation parameters need to be corrected, a correction unit for correcting part of the irradiation parameters when the judgment unit determines that the irradiation parameters need to be corrected, and a storage unit for storing the irradiation parameters, wherein the correction unit periodically corrects the irradiation parameters stored in the storage unit for executing the treatment plan; When the percentage of the real-time neutron dose detected by the detection system to the preset neutron dose in the treatment plan is greater than or equal to a preset value, the determination unit of the monitoring system determines that the irradiation parameters need to be corrected, and the correction unit adjusts the neutron dose rate to a first neutron dose rate that is less than the preset neutron dose rate; When the percentage of the real-time neutron dose detected by the detection system to the preset neutron dose is less than a preset value, the real-time neutron dose rate is kept unchanged or the irradiation time is kept unchanged.

2. The neutron capture therapy device according to claim 1, characterized in that: The error-proof operation system includes a secondary confirmation unit, which is used to transmit a signal to the monitoring system that all information has been confirmed to be correct. Before the secondary confirmation unit is activated, the neutron capture therapy device cannot be started to perform neutron beam irradiation.

3. The neutron capture therapy device according to claim 2, characterized in that: The error-proof operation system includes a fool-proofing part, and the monitoring system includes an input part for inputting and modifying irradiation parameters and control instructions. During the activation of the fool-proofing part, the input part is locked.

4. The neutron capture therapy device according to claim 3, characterized in that: The invention also comprises a button for generating a report, wherein the button for generating a report is locked during the activation of the fool-proofing unit.

5. The neutron capture therapy device according to claim 4, characterized in that: The secondary confirmation unit is a confirmation button for confirming that the information input from the input unit is correct.

6. The neutron capture therapy device according to claim 5, characterized in that: The foolproof part is a start irradiation button for starting the neutron capture therapy device to perform neutron beam irradiation.

7. The neutron capture therapy device according to claim 6, characterized in that: The irradiation pause button is also included. After the irradiation pause button is activated, the irradiation start button can be directly activated again to implement neutron beam irradiation with the original irradiation parameters and instructions.

8. The neutron capture therapy device according to claim 6, characterized in that: It also includes a cancel irradiation button. After activating the cancel irradiation button, all irradiation parameters are cleared. When implementing neutron beam irradiation again, it is necessary to re-enter the irradiation parameters and activate the confirmation information correct button and the start irradiation button in sequence.

9. The neutron capture therapy device according to claim 3, characterized in that: The monitoring system further comprises a control unit for executing a treatment plan according to the irradiation parameters stored in the storage unit and a display unit for displaying the remaining irradiation time or the remaining irradiation time and at least part of the irradiation parameters in real time.

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