CN118045298A - Proton beam range on-line measurement method, device and equipment based on detector - Google Patents
Proton beam range on-line measurement method, device and equipment based on detector Download PDFInfo
- Publication number
- CN118045298A CN118045298A CN202410202210.2A CN202410202210A CN118045298A CN 118045298 A CN118045298 A CN 118045298A CN 202410202210 A CN202410202210 A CN 202410202210A CN 118045298 A CN118045298 A CN 118045298A
- Authority
- CN
- China
- Prior art keywords
- detector
- proton beam
- proton
- gamma
- time
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000691 measurement method Methods 0.000 title claims abstract description 28
- 239000002245 particle Substances 0.000 claims abstract description 180
- 238000001514 detection method Methods 0.000 claims abstract description 122
- 238000000034 method Methods 0.000 claims abstract description 45
- 238000001228 spectrum Methods 0.000 claims abstract description 40
- 238000013507 mapping Methods 0.000 claims abstract description 22
- 238000004458 analytical method Methods 0.000 claims abstract description 17
- 230000008569 process Effects 0.000 claims abstract description 17
- 238000012545 processing Methods 0.000 claims abstract description 10
- 230000001052 transient effect Effects 0.000 claims description 18
- 238000004590 computer program Methods 0.000 claims description 14
- 230000005540 biological transmission Effects 0.000 claims description 9
- 239000013598 vector Substances 0.000 claims description 7
- 230000000737 periodic effect Effects 0.000 claims description 6
- 238000004891 communication Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 238000005259 measurement Methods 0.000 abstract description 15
- 230000008021 deposition Effects 0.000 abstract description 6
- 238000001959 radiotherapy Methods 0.000 abstract description 4
- 230000005855 radiation Effects 0.000 abstract description 3
- 238000013461 design Methods 0.000 description 23
- 206010028980 Neoplasm Diseases 0.000 description 6
- 238000009826 distribution Methods 0.000 description 6
- 230000003993 interaction Effects 0.000 description 6
- 238000003860 storage Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000002661 proton therapy Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 3
- 239000000523 sample Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000002560 therapeutic procedure Methods 0.000 description 3
- 238000000342 Monte Carlo simulation Methods 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 2
- 239000004926 polymethyl methacrylate Substances 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000012795 verification Methods 0.000 description 2
- 241001497337 Euscorpius gamma Species 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 201000011510 cancer Diseases 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000009201 electron therapy Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000005251 gamma ray Effects 0.000 description 1
- 230000005283 ground state Effects 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000005658 nuclear physics Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 210000000056 organ Anatomy 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000011164 primary particle Substances 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 239000011163 secondary particle Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000000528 statistical test Methods 0.000 description 1
- 238000011287 therapeutic dose Methods 0.000 description 1
- 230000001225 therapeutic effect Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- 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
-
- 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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/29—Measurement performed on radiation beams, e.g. position or section of the beam; Measurement of spatial distribution of radiation
Landscapes
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- Pathology (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Radiology & Medical Imaging (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Molecular Biology (AREA)
- Spectroscopy & Molecular Physics (AREA)
- High Energy & Nuclear Physics (AREA)
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Measurement Of Radiation (AREA)
Abstract
The invention discloses a proton beam range on-line measurement method, device and equipment based on a detector, and relates to the technical field of radiotherapy and radiation detection. The method comprises the steps of firstly detecting instantaneous gamma particles generated in a target body by using a detector in the process of entering the target body by proton beam, obtaining the time difference of each instantaneous gamma particle from the entering moment of protons to the arrival moment of the particles, then counting to obtain instantaneous gamma time spectrums according to the time differences of all the instantaneous gamma particles, carrying out statistical moment analysis processing on the instantaneous gamma time spectrums to obtain a time difference average value, and finally determining the range of the proton beam after entering the target body by combining the known mapping relation of the time difference and the proton beam range, thereby greatly reducing the measurement cost, improving the system stability, effectively reducing the statistical noise, improving the accuracy of proton treatment dose deposition, and further determining the detector angle according to the clinical actual proton energy interval so as to improve the detection efficiency.
Description
Technical Field
The invention belongs to the technical field of radiotherapy and radiation detection, and particularly relates to a proton beam range on-line measurement method, device and equipment based on a detector.
Background
Proton therapy is a radiation therapy approach to precisely treat malignant tumors (e.g., cancers), and is most advantageous compared to conventional photon therapy or electron therapy in that it has a special physical property, namely, the bragg peak (Braggpeak), i.e., the irradiation dose profile of the proton beam in the medium (e.g., in the human body) is slowly raised with the advancing direction, then gradually raised until the maximum dose deposition occurs at the bragg peak, and then the profile is rapidly lowered and goes to zero. The Bragg peak characteristic of the protons can enable the tumor focus area to receive the maximum irradiation dose, and enable normal organs behind the focus to be protected from radiation damage, so that the side effect of treatment is reduced. In addition, proton beams with different energies can be used for treating tumors with different depths, and the proton beams basically propagate along a straight line and hardly scatter, so that tumors with different sizes and shapes can be effectively treated.
The proton beam, when passing through human tissue, undergoes a nuclear reaction, producing gamma rays that can be used for therapeutic monitoring, i.e. gamma rays are produced almost along the entire proton propagation path due to inelastic interactions of protons with the target of human tissue (i.e. after inelastic interactions, the target is excited to a higher energy state and then emits a single photon, i.e. the instant gamma particles return to their ground state), until ending 2-3 mm before the bragg peak (at which time the reaction cross section begins to decrease with decreasing energy). Thus, the emission of the prompt gamma rays is related to the propagation path of protons in the tissue, and the range of the proton beam can be verified by measuring the prompt gamma particles (i.e., prompt gamma rays).
The advantage of the instant gamma-ray imaging technique is that it enables real-time verification of the energy transfer of the proton, since after inelastic interaction with the nucleus, anisotropy (which means that all or part of the chemical, physical etc. properties of the substance change with changes in direction, and exhibit differences in different directions) can be detected within a few nanoseconds, even if only 2Gy/min (i.e. dose rate doserate in units of measure, meaning the dose irradiated per unit time) of therapeutic dose is used in proton therapy, a sufficient quantity of high-energy instant gamma particles can be produced.
Currently, the conventional prompt gamma detection scheme determines the range based on the relation between the yield distribution of the prompt gamma particles along the path along the range direction of the proton beam and the proton beam range, which is called a prompt gamma relative measurement device, but such relative measurement device requires extremely high spatial resolution, thus requiring a dense collimator array, a detector array and a high-integration back-end electronic circuit array, resulting in problems of high cost and poor system stability. In addition, during proton therapy, the instantaneous gamma particles emitted by the target are beneficial in determining the beam range during therapy, and since the instantaneous gamma particles are emitted only when the beam is on, the feasibility of on-line therapy verification using the instantaneous gamma particles depends largely on the design of the high-efficiency detector, and also needs to take into account the influence of the detector receptivity and detection efficiency.
Disclosure of Invention
The invention aims to provide a proton beam range on-line measurement method, a proton beam range on-line measurement device, a proton beam range on-line measurement computer readable storage medium and a proton beam range on-line measurement computer program product, which are used for solving the problems that an existing instantaneous gamma relative measurement device needs a dense collimator array, a detector array and a high-integration back-end electronic circuit array when measuring the proton beam range, and therefore, the problems of high cost and poor system stability are caused.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
in a first aspect, a proton beam range on-line measurement method based on a detector is provided, including:
In the process that a proton beam enters a target body, detecting instant gamma particles generated in the target body by using a detector, and obtaining a time difference of each instant gamma particle from a proton entering moment to a particle reaching moment, wherein the detector is positioned at one side of the target body, and enables the detection direction of the detector to be positioned in the same plane with the advancing direction of the proton beam, the proton beam enters the target body in a periodic form, the proton entering moment refers to the moment when the proton beam enters the target body, and the particle reaching moment refers to the moment when the instant gamma particles reach the detector after the proton beam enters the target body;
after the detected number of the instant gamma particles reaches a preset number threshold, counting to obtain an instant gamma time spectrum according to the time differences of all the instant gamma particles, wherein the instant gamma time spectrum is used for illustrating the detected number of the instant gamma particles corresponding to different time differences;
Carrying out statistical moment analysis processing on the instantaneous gamma time spectrum to obtain a time difference average value;
and determining the range of the proton beam after entering the target body according to the time difference average value and combining the time difference with the first known mapping relation of the proton beam range.
Based on the above-mentioned invention, a new scheme is provided for carrying out on-line measurement of proton beam range based on a detector, namely, firstly, in the process of entering a target object by proton beam, the detector is utilized to detect the instant gamma particles generated in the target object, and the time difference between the instant gamma particles and the arrival time of the particles is obtained, then, according to the time difference of all the instant gamma particles, the instant gamma time spectrum is obtained through statistics, and the statistical moment analysis processing is carried out on the instant gamma time spectrum, so as to obtain the time difference average value, and finally, the range of the proton beam after entering the target object is determined by combining the known mapping relation of time difference and the proton beam range.
In one possible design, the method further comprises:
acquiring the emergent energy of the proton beam or weight factors of different emergent energies;
And determining the optimal included angle between the detection direction and the advancing direction according to the emergent energy of the proton beam or the weight factors of different emergent energies and combining a second known mapping relation of the proton emergent energy and the optimal angle of the detector.
In one possible design, determining the optimal angle between the detection direction and the forward direction according to the weight factors of the different emission energies of the proton beam and the second known mapping relation of the proton emission energy and the optimal angle of the detector includes:
Determining a corresponding alternative optimal included angle between the detection direction and the advancing direction according to the second known mapping relation of the proton emission energy and the detector optimal angle aiming at different emission energies of the proton beam;
Determining an alternative optimal included angle corresponding to the emergent energy with the maximum weight factor as a final optimal included angle between the detection direction and the advancing direction, or calculating a final optimal included angle a E between the detection direction and the advancing direction according to the following formula:
Where K represents the total number of outgoing energies, K represents a positive integer, η k represents a weight factor of the kth outgoing energy, and α S,k represents an alternative optimal included angle corresponding to the kth outgoing energy.
In one possible design, the method further comprises:
Acquiring known generation positions and known emission directions of a plurality of historical prompt gamma particles, wherein the historical prompt gamma particles refer to the prompt gamma particles generated in the target body after the proton beam current historically enters the target body;
determining a detection surface equation of the detector under each included angle of the detection direction and the advancing direction by adopting a point method according to the known center position and the known size parameter of the detector, wherein the detection surface equation comprises a plane equation of a detection surface and boundary conditions;
For each history instant gamma particle in the plurality of history instant gamma particles, determining a corresponding emission linear equation by adopting a point parameter mode according to a corresponding known generation position and a known emission direction;
Judging whether the corresponding detection surface is intersected with the emission straight line of each historical instant gamma particle according to the corresponding detection surface equation and the emission straight line equation of each historical instant gamma particle for each included angle, and counting to obtain the total number of the corresponding historical instant gamma particles with intersection conditions;
And determining a certain included angle corresponding to the maximum total number of the historical instant gamma particles with the intersecting condition as the optimal included angle between the detection direction and the advancing direction.
In one possible design, determining the detection surface equation of the detector at each angle of the detection direction to the advancing direction using the point method based on the known center position of the detector and the known dimensional parameter includes:
When the detector is cylindrical, let an angle α between the detection direction and the advancing direction be α, let a plane of the detection direction and the advancing direction be YZ plane in an XYZ space rectangular coordinate system and the advancing direction be Z axis direction of the XYZ space rectangular coordinate system, and let a three-dimensional coordinate of a known center position of the detector in the XYZ space rectangular coordinate system be (x 0,y0,z0), and further let two known dimensional parameters of the detector be: the length of the cylinder is L, and the diameter of the cylinder is R;
According to the known center position of the detector, the length of the cylinder of the detector and the included angle between the detection direction and the advancing direction, determining the three-dimensional coordinate of the center position of the detection surface of the detector in the XYZ space rectangular coordinate system as
Determining a normal vector (a, b, c) of the detector in the XYZ space rectangular coordinate system according to the known center position of the detector and the center position of a detection surface;
According to the central position of the detection surface of the detector and the normal vector (a, b, c), determining a detection surface equation of the detector in a point method under the condition that an included angle between the detection direction and the advancing direction is alpha:
wherein (x, y, z) represents the three-dimensional coordinates of the point on the detection surface of the detector in the XYZ space rectangular coordinate system.
In one possible design, when the detector employs a scintillator detector, detecting transient gamma particles generated in the target body of interest with the detector includes:
And controlling the scintillator detector to detect only the instant gamma particles which are generated in the target body and have emission energy belonging to a preset energy interval, wherein the energy lower limit of the preset energy interval is lower than 4.438MeV, and the energy upper limit of the preset energy interval is higher than 4.444MeV.
In one possible design, the time difference from the proton entry time to the particle arrival time of each prompt gamma particle is obtained, including:
acquiring known generation positions and known generation moments of each instant gamma particle;
Determining a detection surface equation of the detector under an included angle between the detection direction and the advancing direction by adopting a point method according to the known center position and the known size parameter of the detector, wherein the detection surface equation comprises a plane equation of a detection surface and boundary conditions;
determining, for each of the prompt gamma particles, a corresponding transmission distance from the corresponding known production location to a detection face of the detector according to the detection face equation and the corresponding known production location;
For each instant gamma particle, according to the corresponding known generation time and transmission distance, calculating a corresponding time difference delta t from the proton entering time to the particle arrival time according to the following formula:
Wherein Δt 0,γ represents a first time difference from a proton entering time, which is a time when the proton beam enters the target, to a known generation time of the prompt gamma particles, Δd γ represents a transmission distance of the prompt gamma particles, c v represents a speed of light, and particle arrival time, which is a time when the prompt gamma particles reach the detector after the proton beam enters the target.
In a second aspect, a proton beam range on-line measuring device based on a detector is provided, which comprises a time difference acquisition unit, a time spectrum statistics unit, a statistical moment analysis unit and a proton beam range determination unit which are connected in sequence in a communication manner;
The time difference obtaining unit is configured to detect, with a detector, transient gamma particles generated in a target object during a process of entering the target object by a proton beam, and obtain a time difference between a moment of entering a proton and a moment of reaching a particle of each transient gamma particle, where the detector is located at one side of the target object and makes a detection direction of the detector and a direction of proceeding of the proton beam be located in the same plane, the proton beam enters the target object in a periodic form, the moment of entering a proton beam is a moment of entering the target object by the proton beam, and the moment of reaching the particle is a moment of reaching the detector by the transient gamma particles after the proton beam enters the target object;
The time spectrum statistics unit is used for counting to obtain an instantaneous gamma time spectrum according to the time differences of all the instantaneous gamma particles after the detected number of the instantaneous gamma particles reaches a preset number threshold, wherein the instantaneous gamma time spectrum is used for illustrating the detected number of the instantaneous gamma particles corresponding to different time differences;
the statistical moment analysis unit is used for carrying out statistical moment analysis processing on the instantaneous gamma time spectrum to obtain a time difference average value;
the proton beam range determining unit is configured to determine a range of the proton beam after entering the target object according to the time difference average value and a first known mapping relationship between a time difference and a proton beam range.
In a third aspect, the present invention provides a computer device comprising a memory, a processor and a transceiver in communication connection in sequence, wherein the memory is configured to store a computer program, the transceiver is configured to send and receive messages, and the processor is configured to read the computer program and perform the proton beam range on-line measurement method according to the first aspect or any of the possible designs of the first aspect.
In a fourth aspect, the present invention provides a computer readable storage medium having instructions stored thereon which, when run on a computer, perform the proton beam range on-line measurement method as described in the first aspect or any of the possible designs of the first aspect.
In a fifth aspect, the present invention provides a computer program product comprising a computer program or instructions which, when executed by a computer, implement the proton beam range on-line measurement method as described in the first aspect or any of the possible designs of the first aspect.
The beneficial effect of above-mentioned scheme:
(1) The invention creatively provides a new scheme for carrying out on-line measurement on the proton beam range based on a detector, namely, in the process of leading the proton beam to enter a target body, the detector is utilized to detect instant gamma particles generated in the target body, and the time difference between the instant gamma particles and the arrival time of the particles is obtained, then the instant gamma time spectrum is obtained through statistics according to the time difference of all the instant gamma particles, statistical moment analysis processing is carried out on the instant gamma time spectrum, the average value of the time difference is obtained, finally, the range of the proton beam after entering the target body is determined by combining the time difference and the known mapping relation of the proton beam range, so that as only one detector is needed to be configured, and the instant detected proton beam range is obtained directly based on the instant gamma time spectrum, compared with the traditional gamma camera relative measurement device, the measurement cost is not needed, the stability of the system is greatly reduced, the statistical noise is effectively reduced, the accuracy of proton treatment dose deposition is improved, the tumor treatment is beneficial to carrying out in real time and high efficiency, and the actual application to different depths is convenient;
(2) The angle placement position of the detector can be determined by utilizing the emergent energy of the proton beam or the weight factors of different emergent energies, so that the optimization of the detection angle aiming at the energy range and the optimization of the detection angle aiming at the energy weight are further carried out, and the purpose of optimizing multiple targets to obtain the maximum detection efficiency is realized;
(3) The angle placement position of the detector can be determined by utilizing the emission angle of the instant gamma particles, so that the aim of optimizing multiple targets to obtain the maximum detection efficiency is fulfilled;
(4) The instantaneous gamma distribution information generated by protons in radiotherapy can be effectively utilized, and the influence of other secondary particles such as neutrons and the like is effectively avoided.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a flow chart of a proton beam range on-line measurement method based on a detector according to an embodiment of the present application.
Fig. 2 is a diagram illustrating a positional relationship between a probe and a target body according to an embodiment of the present application.
FIG. 3 is a graph illustrating an example of normalized prompt gamma particle emission count in a target provided in accordance with an embodiment of the present application.
FIG. 4 is an exemplary plot of normalized prompt gamma particle emission angles in a target provided in accordance with an embodiment of the present application.
FIG. 5 is an exemplary plot of an instantaneous gamma time spectrum obtained by detecting instantaneous gamma particles at different angles according to an embodiment of the present application.
Fig. 6 is an exemplary diagram of a known mapping relationship between time difference and proton beam range according to an embodiment of the present application.
FIG. 7 is a graph showing an example of the particle count results obtained by detecting transient gamma particles at different angles according to an embodiment of the present application.
Fig. 8 is a diagram illustrating a known mapping relationship between proton emission energy and an optimal angle of a detector according to an embodiment of the present application.
Fig. 9 is a schematic structural diagram of a proton beam range on-line measurement device based on a detector according to an embodiment of the present application.
Fig. 10 is a schematic structural diagram of a computer device according to an embodiment of the present application.
In the above figures: 100-target body of the target; 200-detector.
Detailed Description
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be briefly described below with reference to the accompanying drawings and the description of the embodiments or the prior art, and it is obvious that the following description of the structure of the drawings is only some embodiments of the present invention, and other drawings can be obtained according to these drawings without inventive effort to a person skilled in the art. It should be noted that the description of these examples is for aiding in understanding the present invention, but is not intended to limit the present invention.
It should be understood that although the terms first and second, etc. may be used herein to describe various objects, these objects should not be limited by these terms. These terms are only used to distinguish one object from another. For example, a first object may be referred to as a second object, and similarly a second object may be referred to as a first object, without departing from the scope of example embodiments of the invention.
It should be understood that for the term "and/or" that may appear herein, it is merely one association relationship that describes an associated object, meaning that there may be three relationships, e.g., a and/or B, may represent: three cases of A alone, B alone or both A and B exist; as another example, A, B and/or C may represent the presence of any one of A, B and C or any combination thereof; for the term "/and" that may appear herein, which is descriptive of another associative object relationship, it means that there may be two relationships, e.g., a/and B, it may be expressed that: the two cases of A and B exist independently or simultaneously; in addition, for the character "/" that may appear herein, it is generally indicated that the context associated object is an "or" relationship.
Examples:
As shown in fig. 1 to 2, the proton beam range online measurement method based on the detector provided in the first aspect of the present embodiment may be, but not limited to, executed by a computer device having a certain computing resource and being communicatively connected to the detector, for example, executed by a computer device such as a proton therapy control host or a cloud server. As shown in fig. 1, the proton beam range online measurement method may include, but is not limited to, the following steps S1 to S4.
S1, in the process that a proton beam enters a target body, utilizing a detector to detect instant gamma particles generated in the target body, and obtaining a time difference of each instant gamma particle from the entering time of the proton to the reaching time of the particle, wherein the detector is positioned on one side of the target body, and enables the detection direction of the detector to be positioned in the same plane with the advancing direction of the proton beam, the proton beam enters the target body in a periodic form, the entering time of the proton beam is the time when the proton beam enters the target body, and the reaching time of the particle is the time when the instant gamma particles reach the detector after the proton beam enters the target body.
In the step S1, the target may be PMMA (Polymethyl Methacrylate ) target for measurement experiments, or may be a human body undergoing proton therapy. The detector may be implemented, but is not limited to, using a scintillator detector in the form of a cylinder. As shown in fig. 2, for example, the detector 200 is located at the left side of the target body 100, the target body 100 is an origin of an XYZ space rectangular coordinate system, a plane where the detection direction and the advancing direction are located is a YZ plane in the XYZ space rectangular coordinate system, the advancing direction is a Z axis direction of the XYZ space rectangular coordinate system, and the detection direction and the advancing direction have a certain included angle to determine a detection plane direction of the detector.
In the step S1, the instant gamma particles refer to gamma particles after rejecting slow-release gamma particles (which are derived from decay of nuclides, because half-life periods of the nuclides far exceed proton emergence periods, the long-term existence of the nuclides in the whole treatment process is maintained, and because the nuclides are derived from interactions of neutrons and substances in the treatment process, the nuclides belong to third-stage particles, primary particles, namely, range and energy information of initial protons are difficult to reflect, and therefore, conventional rejection is needed to reduce measurement errors) and exist only in ns-stage time after collision of protons and material atoms. The prompt gamma particles originate from a nuclear reaction, the number of which is dependent on the cross-section of the nuclear interaction; the instant gamma particles are generated along the proton advancing motion path, and the emission quantity of the instant gamma particles at a certain path x p isAnd the number of transient gamma particle emissions over the entire path isIn the target object, considering that the interaction of protons with 12 C and 16 O results in discrete transient gamma particle emissions, the transient gamma particles will therefore emit in various directions, and the number of emergent particles in various directions is not necessarily the same, with angular distribution characteristics (which means that under certain conditions the differential cross section varies as a function of the angle of emergence relative to the direction of the incident particle beam, this concept being important for understanding some phenomena in the physical and nuclear physics of the particle, in particular the shape of the angular distribution is generally related to the characteristics of the reaction channel it relates to and to the energy of the incident particle, and may vary with the chosen coordinate system), for example the probability of emergent particles in a unit solid angle in the (θ, α) direction isFor a given beam and detector model g (E) and differential sectionThe number of prompt gamma particles m detected for each cycle of incident protons can be described asWhere σ is the mass concentration of the target element (i.e., 12 C element, 16 O element, etc.), NA is the avogalileo constant, and Ar is the relative atomic mass of the target element. Specifically, examples of transient gamma generated in the target body by protons having an emission energy of 150MeV can be evaluated by using monte carlo simulation (also referred to as a computer random simulation method, a statistical test method, a calculation method based on "random numbers", or a numerical simulation method that is a subject of a probability phenomenon): the total instantaneous gamma particle count generated in the target body is normalized to the total incident proton number, and information about the generation position, the emission direction, the emission energy, the generation time and the like of the instantaneous gamma particles can be obtained (the information is obtained through Monte Carlo simulation and corresponds to the original data set of the instantaneous gamma particles; for incident protons with different emission energy, a plurality of data sets exist, so that the data sets are processed and screened by the method of the embodiment, and the like, the gamma quantity obtained by different detector angles can be obtained, and the detection angle corresponding to the maximum gamma quantity is the optimal detection angle). For example, fig. 3 shows the relationship between the incidence depth of the proton and the instantaneous gamma particle emitted from each proton, and fig. 4 shows the relationship between the emission angle of the instantaneous gamma particle and the incidence depth of the proton, wherein the angle is normalized to the emission direction of the proton beam.
In the step S1, preferably, when the detector employs a scintillator detector, the transient gamma particles generated in the target body of interest are detected by the detector, including but not limited to: and controlling the scintillator detector to detect only the instant gamma particles which are generated in the target body and have emission energy belonging to a preset energy interval, wherein the energy lower limit of the preset energy interval is lower than 4.438MeV, and the energy upper limit of the preset energy interval is higher than 4.444MeV. Considering that the prompt gamma particles are mainly generated by the de-excitation of 12 C (the emission energy of the corresponding particles is 4.438 MeV) and 11 B (the emission energy of the corresponding particles is 4.444 MeV), if the initial energy region of interest is 3.1MeV-4.6MeV (but not limited to this energy region), only particles with the detection emission energy of about 4.44MeV can be reserved, so that the emission energy region of further interest covers the full energy peak, shan Taoyi peak, double escape peak and the like of the prompt gamma particles, and the balance of noise removal and detection efficiency is realized (namely, as the energy region is larger, the noise is smaller, the signal to noise ratio is higher, but the detection efficiency is reduced, and the comprehensive consideration should be taken into consideration).
In the step S1, the time difference from the proton entering time to the particle reaching time of each instant gamma particle is used for obtaining an instant gamma time spectrum by subsequent statistics, preferably, the time difference from the proton entering time to the particle reaching time of each instant gamma particle is obtained, including but not limited to the following steps S11 to S14.
S11, obtaining known generation positions and known generation moments of all the instant gamma particles.
S12, determining a detection surface equation of the detector under an included angle between the detection direction and the advancing direction by adopting a point method according to the known center position and the known size parameter of the detector, wherein the detection surface equation comprises a plane equation of a detection surface and boundary conditions.
S13, determining the transmission distance from the corresponding known generation position to the detection surface of the detector according to the detection surface equation and the corresponding known generation position aiming at each instant gamma particle;
S14, calculating a corresponding time difference delta t from the proton entering time to the particle arrival time according to the corresponding known generation time and transmission distance aiming at each instant gamma particle according to the following formula:
Wherein Δt 0,γ represents a first time difference from a proton entering time, which is a time when the proton beam enters the target, to a known generation time of the prompt gamma particles, Δd γ represents a transmission distance of the prompt gamma particles, c v represents a speed of light, and particle arrival time, which is a time when the prompt gamma particles reach the detector after the proton beam enters the target.
In the step S1, the time difference between the moment of entering the proton and the moment of reaching the particle of each instant gamma particle may also be measured directly by using an existing timer with an accuracy of more than nanoseconds, that is, the timer is started to count at the moment of entering the target body by the proton beam, and stopped when the detector detects a certain instant gamma particle, and the last obtained time difference is taken as the time difference between the moment of entering the proton and the moment of reaching the particle of the certain instant gamma particle.
S2, after the detected number of the instant gamma particles reaches a preset number threshold, counting to obtain an instant gamma time spectrum according to the time differences of all the instant gamma particles, wherein the instant gamma time spectrum is used for illustrating the detected number of the instant gamma particles corresponding to different time differences.
In the step S2, the preset number threshold is used as a reliability criterion of the prompt gamma time spectrum, that is, a certain reliability is only provided when the detected number of the prompt gamma particles reaches a certain number; if not, the detection is continued through the step S1 when the proton beam enters the next period of emission after the period of the proton beam is completed. The specific statistical process of the prompt gamma time spectrum can be conventionally obtained based on statistical knowledge, for example, as shown in fig. 5.
S3, carrying out statistical moment analysis processing on the instantaneous gamma time spectrum to obtain a time difference average value.
In the step S3, as shown in fig. 5, since the prompt gamma time spectrum is normally distributed, the statistical moment analysis process may be conventionally completed based on the normal distribution characteristics, to obtain the average value μ of the time difference and the relevant statistical moment parameters such as the standard deviation σ.
S4, determining the range of the proton beam after entering the target body according to the time difference average value and combining the time difference with the first known mapping relation of the proton beam range.
In said step S4, it is considered that as the time of flight of the proton in the target increases, the average value of the time difference increases, so that the spread of the instantaneous gamma time spectrum also increases, i.e. the standard deviation σ increases, and therefore, such statistical distribution contains information about the proton beam range, i.e. when the proton beam range changes, the value of the statistical parameter also changes, e.g. the time difference has a fitting relation with the proton beam range and can be known in advance, as shown in fig. 6, and the count of instantaneous gamma instances has a fitting relation with the angle of the detection direction and the advancing direction and can be known in advance, as shown in fig. 7.
The method for measuring the proton beam range on line is based on the method for measuring the proton beam range on line described in the steps S1 to S4, namely, a new scheme for measuring the proton beam range on line based on a detector is provided, namely, in the process that the proton beam enters a target body, the detector is used for detecting instantaneous gamma particles generated in the target body, the time difference between the moment of entering the instantaneous gamma particles and the moment of reaching the particles is obtained, then the instantaneous gamma time spectrum is obtained through statistics according to the time difference of all the instantaneous gamma particles, the statistical moment analysis processing is carried out on the instantaneous gamma time spectrum to obtain a time difference average value, finally, the range of the proton beam after entering the target body is determined by combining the known mapping relation between the time difference and the proton beam range, and therefore, as only one detector is needed to be configured, the proton beam range which is detected in real time based on the instantaneous gamma time spectrum, compared with the traditional gamma camera, the method for measuring the time difference is not needed, the space response is not needed, the measurement cost is greatly reduced, the system stability is improved, the statistical noise is effectively reduced, the statistical noise is improved, the actual deposition is improved, the same, the method is not suitable for the actual deposition depth is convenient, and the actual application is convenient.
The present embodiment provides a possible design of how to achieve the maximum detection efficiency based on the technical solution of the first aspect, i.e. considering that protons with different energies have different ranges, and for protons with different energies, the method preferably further includes, but is not limited to, the following steps S51 to S52 in order to obtain the maximum detection efficiency.
S51, acquiring the emergent energy of the proton beam or the weight factors of different emergent energies.
In the step S51, the specific acquisition mode of the emission energy of the proton beam or the weighting factors of different emission energies may be, but is not limited to, directly read from the proton treatment plan.
S52, determining the optimal included angle between the detection direction and the advancing direction according to the emergent energy of the proton beam or the weight factors of different emergent energies and combining the second known mapping relation of the proton emergent energy and the optimal angle of the detector.
In the step S52, specifically, according to the weight factors of the different emission energies of the proton beam, the optimum included angle between the detection direction and the advancing direction is determined in combination with the second known mapping relationship between the proton emission energy and the optimum angle of the detector, including but not limited to the following steps S521-S522.
S521, determining a corresponding alternative optimal included angle between the detection direction and the advancing direction according to the second known mapping relation of the proton emission energy and the optimal angle of the detector aiming at the different emission energies of the proton beam.
In the step S521, the second known mapping relationship between the proton emission energy and the optimal angle of the detector is as shown in fig. 8, for example: aiming at the emergent energy of 70-100 MeV, the optimal angle of the corresponding detector is 60 degrees; aiming at the emergent energy of 110-150 MeV, the optimal angle of the corresponding detector is 45 degrees; aiming at the emergent energy of 160-200 MeV, the optimal angle of the corresponding detector is 45 degrees; etc.
S522, determining an alternative optimal included angle corresponding to the emergent energy with the maximum weight factor as a final optimal included angle between the detection direction and the advancing direction, or calculating to obtain a final optimal included angle a E between the detection direction and the advancing direction according to the following formula:
Where K represents the total number of outgoing energies, K represents a positive integer, η k represents a weight factor of the kth outgoing energy, and α S,k represents an alternative optimal included angle corresponding to the kth outgoing energy.
In the step S522, for example, if the different emission energies of the proton beam are respectively 70MeV, 90MeV, 130MeV and the weighting factors are respectively 1:2:4, an alternative optimal included angle corresponding to 130MeV and being 45 degrees can be selected to be determined as a final optimal included angle between the detection direction and the advancing direction, or a formula based on the following formula can be adoptedThe calculated 51.4 degree is determined as the final optimal angle of the detection direction and the advancing direction.
Based on the above possible design, the angle placement position of the detector can be determined by utilizing the emergent energy of the proton beam or the weight factors of different emergent energies, so that the detection angle of the energy range is optimized, the detection angle of the energy weight is optimized, the purpose of optimizing multiple targets to obtain the maximum detection efficiency is achieved, the optimal detector angle can be determined according to the energy interval range of the clinical treatment beam, the detection efficiency is improved, the statistical noise can be further effectively reduced, the deposition accuracy of proton treatment doses is improved, and the treatment of tumors with different depths is facilitated in real time and high efficiency.
The present embodiment provides another possible design of how to achieve the maximum detection efficiency based on the technical solution of the first aspect, namely considering that when the transient gamma particles are generated at a certain path, the transient gamma particles can be detected by the detector only within a certain angle range, and the size of the angle range depends on the placement of the detector and the size of the detector, and in order to obtain the maximum detection efficiency, the method preferably further includes, but is not limited to, the following steps S61-S65.
S61, obtaining known generation positions and known emission directions of a plurality of historical prompt gamma particles, wherein the historical prompt gamma particles are prompt gamma particles generated in the target body after the proton beam current historically enters the target body.
S62, determining a detection surface equation of the detector under each included angle of the detection direction and the advancing direction by adopting a point method according to the known center position and the known size parameter of the detector, wherein the detection surface equation comprises a plane equation of a detection surface and boundary conditions.
In step S62, specifically, according to the known center position and the known size parameter of the probe, a detection surface equation of the probe under each included angle between the detection direction and the advancing direction is determined by using a dot method, including, but not limited to, the following steps S621 to S624.
S621. when the detector is cylindrical, let an angle α between the detection direction and the advancing direction be α, let a plane in which the detection direction and the advancing direction lie be YZ plane in XYZ space rectangular coordinate system and the advancing direction be Z axis direction of the XYZ space rectangular coordinate system, and let a three-dimensional coordinate of a known center position of the detector in the XYZ space rectangular coordinate system be (x 0,y0,z0), and also let two known dimensional parameters of the detector be: the cylinder length is L and the cylinder diameter is R.
S622, determining the three-dimensional coordinate of the center position of the detection surface of the detector in the XYZ space rectangular coordinate system as
S623, determining normal vectors (a, b, c) of the detector in the XYZ space rectangular coordinate system according to the known center position of the detector and the center position of a detection surface.
S624, determining a detection surface equation of the detector under the condition that the included angle between the detection direction and the advancing direction is alpha by adopting a point method according to the central position of the detection surface of the detector and the normal vector (a, b, c):
wherein (x, y, z) represents the three-dimensional coordinates of the point on the detection surface of the detector in the XYZ space rectangular coordinate system.
S63, determining a corresponding emission linear equation by adopting a point-parameter mode according to a corresponding known generation position and a known emission direction for each historical instant gamma particle in the plurality of historical instant gamma particles.
In the step S63, specifically, assuming that the three-dimensional coordinate of the known generation position of a certain historical prompt gamma particle in the XYZ space rectangular coordinate system is (x 2,y2,z2) and the known emission direction vector of the certain historical prompt gamma particle in the XYZ space rectangular coordinate system is (m, n, p), determining an emission linear equation of the certain historical prompt gamma particle by using a point parameter method is as follows:
Where t represents the emission duration.
S64, judging whether the corresponding detection surface is intersected with the emission straight line of each historical instant gamma particle according to the corresponding detection surface equation and the emission straight line equation of each historical instant gamma particle for each included angle, and counting to obtain the total number of the corresponding historical instant gamma particles with the intersecting condition.
S65, determining a certain included angle corresponding to the maximum total number of the historical instant gamma particles with the intersecting condition as the optimal included angle between the detection direction and the advancing direction.
Based on the second design, the angle placement position of the detector can be determined by utilizing the emission angle of the instant gamma particles, so that the aim of optimizing multiple targets to obtain the maximum detection efficiency is fulfilled.
As shown in fig. 9, a second aspect of the present embodiment provides a virtual device for implementing the proton beam range online measurement method according to the first aspect or any of the designs in the first aspect, where the virtual device includes a time difference acquisition unit, a time spectrum statistics unit, a statistical moment analysis unit, and a proton beam range determination unit that are sequentially connected in communication;
The time difference obtaining unit is configured to detect, with a detector, transient gamma particles generated in a target object during a process of entering the target object by a proton beam, and obtain a time difference between a moment of entering a proton and a moment of reaching a particle of each transient gamma particle, where the detector is located at one side of the target object and makes a detection direction of the detector and a direction of proceeding of the proton beam be located in the same plane, the proton beam enters the target object in a periodic form, the moment of entering a proton beam is a moment of entering the target object by the proton beam, and the moment of reaching the particle is a moment of reaching the detector by the transient gamma particles after the proton beam enters the target object;
The time spectrum statistics unit is used for counting to obtain an instantaneous gamma time spectrum according to the time differences of all the instantaneous gamma particles after the detected number of the instantaneous gamma particles reaches a preset number threshold, wherein the instantaneous gamma time spectrum is used for illustrating the detected number of the instantaneous gamma particles corresponding to different time differences;
the statistical moment analysis unit is used for carrying out statistical moment analysis processing on the instantaneous gamma time spectrum to obtain a time difference average value;
the proton beam range determining unit is configured to determine a range of the proton beam after entering the target object according to the time difference average value and a first known mapping relationship between a time difference and a proton beam range.
The working process, working details and technical effects of the foregoing apparatus provided in the second aspect of the present embodiment may refer to the first aspect or any possible design of the proton beam range online measurement method in the first aspect, which are not described herein.
As shown in fig. 10, a third aspect of the present embodiment provides a computer device for executing the proton beam range online measurement method according to the first aspect or any of the possible designs in the first aspect, including a memory, a processor, and a transceiver, which are sequentially communicatively connected, where the memory is configured to store a computer program, the transceiver is configured to send and receive a message, and the processor is configured to read the computer program, and execute the proton beam range online measurement method according to the first aspect or any of the possible designs in the first aspect. By way of specific example, the Memory may include, but is not limited to, random-Access Memory (RAM), read-Only Memory (ROM), flash Memory (Flash Memory), first-in first-out Memory (First Input First Output, FIFO), and/or first-out Memory (First Input Last Output, FILO), etc.; the processor may be, but is not limited to, a microprocessor of the type STM32F105 family. In addition, the computer device may include, but is not limited to, a power module, a display screen, and other necessary components.
The working process, working details and technical effects of the foregoing computer device provided in the third aspect of the present embodiment may refer to the first aspect or any possible design of the proton beam range online measurement method in the first aspect, which are not described herein.
A fourth aspect of the present embodiment provides a computer readable storage medium storing instructions comprising the proton beam range online measurement method as described in the first aspect or any of the possible designs in the first aspect, i.e. the computer readable storage medium has instructions stored thereon that, when executed on a computer, perform the proton beam range online measurement method as described in the first aspect or any of the possible designs in the first aspect. The computer readable storage medium refers to a carrier for storing data, and may include, but is not limited to, a floppy disk, an optical disk, a hard disk, a flash Memory, and/or a Memory Stick (Memory Stick), where the computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable devices.
The working process, working details and technical effects of the foregoing computer readable storage medium provided in the fourth aspect of the present embodiment may refer to the proton beam range online measurement method as described in the first aspect or any possible design in the first aspect, and will not be described herein.
A fifth aspect of the present embodiments provides a computer program product comprising a computer program or instructions which, when executed by a computer, implement the proton beam range online measurement method as described in the first aspect or any of the possible designs in the first aspect. Wherein the computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus.
Finally, it should be noted that: the foregoing description is only of the preferred embodiments of the invention and is not intended to limit the scope of the invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The proton beam range on-line measurement method based on the detector is characterized by comprising the following steps of:
In the process that a proton beam enters a target body, detecting instant gamma particles generated in the target body by using a detector, and obtaining a time difference of each instant gamma particle from a proton entering moment to a particle reaching moment, wherein the detector is positioned at one side of the target body, and enables the detection direction of the detector to be positioned in the same plane with the advancing direction of the proton beam, the proton beam enters the target body in a periodic form, the proton entering moment refers to the moment when the proton beam enters the target body, and the particle reaching moment refers to the moment when the instant gamma particles reach the detector after the proton beam enters the target body;
after the detected number of the instant gamma particles reaches a preset number threshold, counting to obtain an instant gamma time spectrum according to the time differences of all the instant gamma particles, wherein the instant gamma time spectrum is used for illustrating the detected number of the instant gamma particles corresponding to different time differences;
Carrying out statistical moment analysis processing on the instantaneous gamma time spectrum to obtain a time difference average value;
and determining the range of the proton beam after entering the target body according to the time difference average value and combining the time difference with the first known mapping relation of the proton beam range.
2. The proton beam range on-line measurement method as recited in claim 1, further comprising:
acquiring the emergent energy of the proton beam or weight factors of different emergent energies;
And determining the optimal included angle between the detection direction and the advancing direction according to the emergent energy of the proton beam or the weight factors of different emergent energies and combining a second known mapping relation of the proton emergent energy and the optimal angle of the detector.
3. The method according to claim 1, wherein determining the optimal angle between the detection direction and the forward direction according to the weighting factors of the different emission energies of the proton beams and the second known mapping relationship between the proton emission energy and the optimal angle of the detector comprises:
Determining a corresponding alternative optimal included angle between the detection direction and the advancing direction according to the second known mapping relation of the proton emission energy and the detector optimal angle aiming at different emission energies of the proton beam;
Determining an alternative optimal included angle corresponding to the emergent energy with the maximum weight factor as a final optimal included angle between the detection direction and the advancing direction, or calculating a final optimal included angle a E between the detection direction and the advancing direction according to the following formula:
Where K represents the total number of outgoing energies, K represents a positive integer, η k represents a weight factor of the kth outgoing energy, and α S,k represents an alternative optimal included angle corresponding to the kth outgoing energy.
4. The proton beam range on-line measurement method as recited in claim 1, further comprising:
Acquiring known generation positions and known emission directions of a plurality of historical prompt gamma particles, wherein the historical prompt gamma particles refer to the prompt gamma particles generated in the target body after the proton beam current historically enters the target body;
determining a detection surface equation of the detector under each included angle of the detection direction and the advancing direction by adopting a point method according to the known center position and the known size parameter of the detector, wherein the detection surface equation comprises a plane equation of a detection surface and boundary conditions;
For each history instant gamma particle in the plurality of history instant gamma particles, determining a corresponding emission linear equation by adopting a point parameter mode according to a corresponding known generation position and a known emission direction;
Judging whether the corresponding detection surface is intersected with the emission straight line of each historical instant gamma particle according to the corresponding detection surface equation and the emission straight line equation of each historical instant gamma particle for each included angle, and counting to obtain the total number of the corresponding historical instant gamma particles with intersection conditions;
And determining a certain included angle corresponding to the maximum total number of the historical instant gamma particles with the intersecting condition as the optimal included angle between the detection direction and the advancing direction.
5. The proton beam range on-line measuring method as claimed in claim 4, wherein determining a detection surface equation of the detector at each angle of the detection direction and the forward direction using a point method based on a known center position of the detector and a known dimensional parameter, comprises:
When the detector is cylindrical, let an angle α between the detection direction and the advancing direction be α, let a plane of the detection direction and the advancing direction be YZ plane in an XYZ space rectangular coordinate system and the advancing direction be Z axis direction of the XYZ space rectangular coordinate system, and let a three-dimensional coordinate of a known center position of the detector in the XYZ space rectangular coordinate system be (x 0,y0,z0), and further let two known dimensional parameters of the detector be: the length of the cylinder is L, and the diameter of the cylinder is R;
According to the known center position of the detector, the length of the cylinder of the detector and the included angle between the detection direction and the advancing direction, determining the three-dimensional coordinate of the center position of the detection surface of the detector in the XYZ space rectangular coordinate system as
Determining a normal vector (a, b, c) of the detector in the XYZ space rectangular coordinate system according to the known center position of the detector and the center position of a detection surface;
According to the central position of the detection surface of the detector and the normal vector (a, b, c), determining a detection surface equation of the detector in a point method under the condition that an included angle between the detection direction and the advancing direction is alpha:
wherein (x, y, z) represents the three-dimensional coordinates of the point on the detection surface of the detector in the XYZ space rectangular coordinate system.
6. The proton beam range on-line measurement method as claimed in claim 1, wherein when the detector employs a scintillator detector, detecting the prompt gamma particles generated in the target body of interest with the detector, comprising:
And controlling the scintillator detector to detect only the instant gamma particles which are generated in the target body and have emission energy belonging to a preset energy interval, wherein the energy lower limit of the preset energy interval is lower than 4.438MeV, and the energy upper limit of the preset energy interval is higher than 4.444MeV.
7. The proton beam range on-line measurement method as claimed in claim 1, wherein obtaining a time difference from a proton entry time to a particle arrival time of each of the instant gamma particles comprises:
acquiring known generation positions and known generation moments of each instant gamma particle;
Determining a detection surface equation of the detector under an included angle between the detection direction and the advancing direction by adopting a point method according to the known center position and the known size parameter of the detector, wherein the detection surface equation comprises a plane equation of a detection surface and boundary conditions;
determining, for each of the prompt gamma particles, a corresponding transmission distance from the corresponding known production location to a detection face of the detector according to the detection face equation and the corresponding known production location;
For each instant gamma particle, according to the corresponding known generation time and transmission distance, calculating a corresponding time difference delta t from the proton entering time to the particle arrival time according to the following formula:
Wherein Δt 0,γ represents a first time difference from a proton entering time, which is a time when the proton beam enters the target, to a known generation time of the prompt gamma particles, Δd γ represents a transmission distance of the prompt gamma particles, c v represents a speed of light, and particle arrival time, which is a time when the prompt gamma particles reach the detector after the proton beam enters the target.
8. The proton beam range on-line measuring device based on the detector is characterized by comprising a time difference acquisition unit, a time spectrum statistics unit, a statistical moment analysis unit and a proton beam range determination unit which are sequentially connected in a communication mode;
The time difference obtaining unit is configured to detect, with a detector, transient gamma particles generated in a target object during a process of entering the target object by a proton beam, and obtain a time difference between a moment of entering a proton and a moment of reaching a particle of each transient gamma particle, where the detector is located at one side of the target object and makes a detection direction of the detector and a direction of proceeding of the proton beam be located in the same plane, the proton beam enters the target object in a periodic form, the moment of entering a proton beam is a moment of entering the target object by the proton beam, and the moment of reaching the particle is a moment of reaching the detector by the transient gamma particles after the proton beam enters the target object;
The time spectrum statistics unit is used for counting to obtain an instantaneous gamma time spectrum according to the time differences of all the instantaneous gamma particles after the detected number of the instantaneous gamma particles reaches a preset number threshold, wherein the instantaneous gamma time spectrum is used for illustrating the detected number of the instantaneous gamma particles corresponding to different time differences;
the statistical moment analysis unit is used for carrying out statistical moment analysis processing on the instantaneous gamma time spectrum to obtain a time difference average value;
the proton beam range determining unit is configured to determine a range of the proton beam after entering the target object according to the time difference average value and a first known mapping relationship between a time difference and a proton beam range.
9. A computer device comprising a memory, a processor and a transceiver in communication connection in sequence, wherein the memory is configured to store a computer program, the transceiver is configured to send and receive messages, and the processor is configured to read the computer program and perform the proton beam range on-line measurement method according to any one of claims 1-7.
10. A computer program product comprising a computer program or instructions, characterized in that the computer program or instructions, when executed by a computer, implement the proton beam range on-line measurement method according to any one of claims 1-7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410202210.2A CN118045298B (en) | 2024-02-23 | Proton beam range on-line measurement method, device and equipment based on detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410202210.2A CN118045298B (en) | 2024-02-23 | Proton beam range on-line measurement method, device and equipment based on detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN118045298A true CN118045298A (en) | 2024-05-17 |
| CN118045298B CN118045298B (en) | 2024-10-22 |
Family
ID=
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150087882A1 (en) * | 2013-09-20 | 2015-03-26 | Ion Beam Applications, S.A. | Method and apparatus for monitoring the range of a particle beam |
| US20150321025A1 (en) * | 2014-05-09 | 2015-11-12 | Ion Beam Applications S.A. | Apparatus for particle therapy verification comprising a collimator with multiple openings |
| CN110095804A (en) * | 2019-04-10 | 2019-08-06 | 南京航空航天大学 | A kind of method and device of carbon ion range/energy measurement |
| US20200316404A1 (en) * | 2019-04-04 | 2020-10-08 | Deutsches Krebsforschungszentrum | Detector and method for tracking an arrival time of single particles in an ion beam |
| CN114206439A (en) * | 2019-07-17 | 2022-03-18 | 费斯博蒂克有限公司 | Device and method for monitoring the treatment of a body part of a patient with particles |
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150087882A1 (en) * | 2013-09-20 | 2015-03-26 | Ion Beam Applications, S.A. | Method and apparatus for monitoring the range of a particle beam |
| US20150321025A1 (en) * | 2014-05-09 | 2015-11-12 | Ion Beam Applications S.A. | Apparatus for particle therapy verification comprising a collimator with multiple openings |
| US20200316404A1 (en) * | 2019-04-04 | 2020-10-08 | Deutsches Krebsforschungszentrum | Detector and method for tracking an arrival time of single particles in an ion beam |
| CN110095804A (en) * | 2019-04-10 | 2019-08-06 | 南京航空航天大学 | A kind of method and device of carbon ion range/energy measurement |
| CN114206439A (en) * | 2019-07-17 | 2022-03-18 | 费斯博蒂克有限公司 | Device and method for monitoring the treatment of a body part of a patient with particles |
Non-Patent Citations (1)
| Title |
|---|
| 李楠: "基于平板PET监测质子束诱导活度以及剂量估计的仿真研究", 《中国优秀硕士学位论文全文数据库 医药卫生科技辑》, 15 January 2023 (2023-01-15) * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6255552B2 (en) | Neutron detector | |
| Henriquet et al. | Interaction vertex imaging (IVI) for carbon ion therapy monitoring: a feasibility study | |
| Bom et al. | Real-time prompt gamma monitoring in spot-scanning proton therapy using imaging through a knife-edge-shaped slit | |
| Mukha et al. | Observation of Two-Proton Radioactivity of Mg 19 by Tracking the Decay Products | |
| Di Fulvio et al. | Superheated emulsions and track etch detectors for photoneutron measurements | |
| Satoh et al. | Shielding study at the Fukui prefectural hospital proton therapy center | |
| CN118045298B (en) | Proton beam range on-line measurement method, device and equipment based on detector | |
| Zhang | Monte Carlo simulation of mixed neutron-gamma radiation fields and dosimetry devices | |
| CN118045298A (en) | Proton beam range on-line measurement method, device and equipment based on detector | |
| Mousavi Shirazi et al. | Design and Simulation of a New Model for Treatment by NCT | |
| CN110095804B (en) | Method and device for measuring carbon ion range/energy | |
| JP2019154989A (en) | Neutron capture therapy system, and neutron beam detection device | |
| Goldston et al. | Zero knowledge warhead verification: System requirements and detector technologies | |
| Safronava et al. | Monitoring of GeV Deuteron Beam Parameters in ADS Experiments at the Nuclotron (JINR, Dubna) | |
| Mazzaschi et al. | Simulation of photon-nucleon interactions Part II. ν photoproduction with a 4π BGO calorimeter | |
| Chacon et al. | Prompt Gamma based Detection and Discrimination of 2 Neutron Capture Events for NCEPT Dose 3 Quantification | |
| WO2024142755A1 (en) | Measuring device and measuring method for measuring effectiveness of boron neutron capture therapy | |
| Rovituso | Fragmentation and lateral scattering of 120 and 200 MeV/u 4He ions on water targets | |
| CN118369594A (en) | Method and system for dosing | |
| Bonforte | Radiation Physics and Experimental Characterization of the Radiation Fields Produced by a Heavy Ion Accelerator for Medical Applications | |
| Cinausero et al. | A proton recoil telescope for neutron spectroscopy | |
| Youwu et al. | Neutron influence in charged particle therapy | |
| Jadrníčková et al. | Spectrometry of linear energy transfer and its use in high-energy particle beams | |
| Wang et al. | Simulation of physical parameters for a photoneutron source | |
| Filimonov | High p T correlations of γ and charged hadrons at RHIC |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant |