A beam dose and position distribution monitoring system and method of use

Abstract

This invention provides a beam dose and position distribution monitoring system and its usage method. The beam dose and position distribution monitoring system includes a detector, a pressure control device, a data acquisition module, a high-voltage module, and a host computer. The detector is equipped with a dose monitoring unit and a position monitoring unit. The pressure control device is connected to the detector to control the internal pressure. The high-voltage module provides the operating voltage required for the detector to perform monitoring. The data acquisition module and the host computer are used to acquire and process the dose and position distribution signals generated by the dose and position monitoring units. Compared with existing technologies, this invention can monitor the beam of both Flash radiotherapy and conventional radiotherapy. It can shorten the preparation time before each Flash radiotherapy session, improve the efficiency and efficacy of the Flash radiotherapy device, and reduce the equipment cost.

Description

Technical Field

[0001] This invention relates to the field of particle radiotherapy technology, and in particular to a beam dose and position distribution monitoring system and its usage method. Background Technology

[0002] Flash radiotherapy (FRT) refers to radiation therapy using ultra-high dose rate ultrafast beam irradiation. The ultra-high dose rate typically exceeds 40 Gy / s, and the irradiation time is generally less than 300 ms. During Flash radiotherapy, tumors and normal tissues exhibit significantly different responses to radiation, effectively protecting normal tissues while killing tumors and reducing adverse reactions. Therefore, Flash radiotherapy can significantly improve the radiation tolerance of normal tissues.

[0003] During radiotherapy, it is generally necessary to monitor the dose and position distribution of the beam. Currently, conventional radiotherapy typically uses ionization chamber detectors to monitor these parameters. However, due to the extremely short beam interlocking time in flash radiotherapy, these ionization chamber detectors are generally unable to monitor the beam in flash radiotherapy. Therefore, various detectors have been developed to monitor the beam in flash radiotherapy, such as silicon detectors, diamond detectors, scintillator detectors, secondary electron detectors, Faraday cylinders, photographic film, and thermoluminescent dosimeters. Furthermore, flash radiotherapy devices can generally also perform conventional radiotherapy. However, most of the detectors mentioned above that can monitor the beam in flash radiotherapy are not suitable for monitoring the dose and position distribution of the beam used in conventional radiotherapy. Therefore, flash radiotherapy devices require two types of detectors, and the appropriate detector must be installed before each radiotherapy session, depending on the type of treatment. This increases the preparation time before each session, thus reducing the efficiency and effectiveness of the flash radiotherapy device; it also increases the equipment cost of the flash radiotherapy device. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of the prior art by providing a beam dose and position distribution monitoring system and method, which can monitor both the dose and position distribution of the beam in Flash radiotherapy and the beam in conventional radiotherapy.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides a beam dose and position distribution monitoring system, comprising:

[0007] The detector includes a housing and an inner core. The housing has an airtight cavity and an air inlet and an air outlet communicating with the airtight cavity. The inner core is disposed in the airtight cavity and includes a dose monitoring unit and a position monitoring unit. The dose monitoring unit and the position monitoring unit are arranged front and rear along the beam injection direction and are isolated from each other.

[0008] A pressure control device, comprising an inflation unit and an exhaust unit, wherein the inflation unit is connected to the air inlet and the exhaust unit is connected to the air outlet, the inflation unit is used to inject working gas into the airtight cavity and the exhaust unit is used to discharge the working gas from the airtight cavity, the inflation unit and the exhaust unit cooperate to control the pressure in the airtight cavity;

[0009] The acquisition module is connected to the dose monitoring unit and the position monitoring unit respectively;

[0010] A high-voltage module is electrically connected to the dose monitoring unit and the position monitoring unit respectively, and is used to provide operating voltage to the dose monitoring unit and the position monitoring unit;

[0011] A host computer is connected to the acquisition module.

[0012] Preferably, the housing includes a frame and a panel that is sealed to the openings on both sides of the frame. The panel has a window and a window plate that is fixedly covered to allow the beam to enter or exit.

[0013] Preferably, the window is further provided with support wires, which provide support to the window panel on one or both sides.

[0014] Preferably, the dose monitoring unit includes a first high-voltage electrode plate, a first insulating plate, and a signal electrode plate stacked in sequence. The first high-voltage electrode plate includes a wire frame with a plurality of gold-plated tungsten wires spaced apart on the wire frame.

[0015] Preferably, the position monitoring unit includes a second high-voltage plate, a second insulating plate, a strip plate, a third insulating plate, and a third high-voltage plate stacked in sequence. The strip plate has a plurality of first signal bars and second signal bars arranged at intervals, and the first signal bars and the second signal bars are perpendicular to each other.

[0016] Preferably, the inflation unit includes a gas cylinder and an air inlet pipe. One end of the air inlet pipe is connected to the gas cylinder, and the other end of the air inlet pipe is connected to the air inlet. A branch pipe is connected to the air inlet pipe, and a first valve is provided on the branch pipe. An airflow regulating component and a pressure regulating component are provided on the air inlet pipe between the air inlet and the branch pipe. A second valve and a pressure reducing valve are provided on the air inlet pipe between the branch pipe and the gas cylinder.

[0017] Preferably, the pressure regulating assembly includes a gauge tube, a solenoid valve, and a vacuum gauge. The gauge tube is located at the end of the air inlet pipe near the air inlet, the solenoid valve is located on the side of the gauge tube away from the air inlet, and the vacuum gauge is connected to both the gauge tube and the solenoid valve.

[0018] Preferably, the gas outlet unit includes a gas outlet pipe and a vacuum pump. One end of the gas outlet pipe is connected to the gas outlet. The vacuum pump is connected to the gas outlet pipe through a connecting pipe. A third valve is provided on the connecting pipe. A flow meter, a gas flow regulating component, and a fourth valve are provided on the gas outlet pipe. The flow meter and the gas flow regulating component are located between the gas outlet and the connecting pipe. The fourth valve is located between the connecting pipe and the other end of the gas outlet pipe.

[0019] Preferably, the acquisition module includes a charge integrating electrometer and electronics, the charge integrating electrometer being connected to the dose monitoring unit, and the electronics being connected to both the position monitoring unit and the charge integrating electrometer.

[0020] In a second aspect, the present invention also provides a method for using the beam dose and location distribution monitoring system as described in the first aspect, comprising the following steps:

[0021] The detector is installed on the terminal frame of the particle flash radiotherapy device;

[0022] According to the type of radiotherapy, the corresponding working gas is injected into the airtight cavity through the air pressure control device, and the air pressure in the airtight cavity is adjusted to be close to the air pressure value required for monitoring the beam used in radiotherapy.

[0023] Connect the power supply to the acquisition module and the high-voltage module, and set the output voltage of the high-voltage module to the required operating voltage of the dose monitoring unit and the position monitoring unit;

[0024] Control the particle Flash radiotherapy device to perform beam firing;

[0025] The acquisition module acquires the dose signal and position distribution signal generated by the dose monitoring unit and the position monitoring unit when the beam passes through the detector. The acquisition module calculates the dose and position distribution information of the beam based on the acquired dose and position distribution signals and transmits it to the host computer. The host computer performs corresponding data processing and displays the results of the dose and position distribution information of the beam transmitted by the acquisition module.

[0026] After radiotherapy, the power supply to the acquisition module and the high-voltage module is turned off. The internal air pressure of the detector is restored to near the ambient air pressure through the air pressure control device. After the internal air pressure of the detector stabilizes, all power is turned off.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] In use, this invention allows for the adjustment of the detector's internal pressure and core voltage to the required values ​​for monitoring beam dose and position distribution, based on the beam type used in each Flash radiotherapy session. This adjustment is achieved through a pressure control device and a high-voltage module, respectively. Therefore, this invention can be used for monitoring both Flash beam dose and position distribution, as well as conventional beam dose and position distribution, without requiring the replacement of different detectors for each Flash radiotherapy session. This reduces preparation time before each Flash radiotherapy session, improving the device's efficiency and radiotherapy effectiveness, while also lowering equipment costs. Attached Figure Description

[0029] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments will be briefly described below. It should be noted that in all the drawings, the elements or parts are not necessarily drawn to actual scale.

[0030] Figure 1 This is a schematic diagram of the overall structure of the beam dose and position distribution detection system described in this embodiment of the invention;

[0031] Figure 2 This is a schematic diagram of the overall detector structure of the beam dose and position distribution detection system described in this embodiment of the invention;

[0032] Figure 3 This is a schematic diagram of the overall structure of the detector panel of the beam dose and position distribution detection system described in this embodiment of the invention;

[0033] Figure 4This is a schematic diagram of the overall structure of the detector core of the beam dose and position distribution detection system described in this embodiment of the invention;

[0034] Figure 5 This is a schematic diagram showing the connection between the detector and the air pressure control device in the beam dose and position distribution detection system described in this embodiment of the invention.

[0035] Figure 6 This is a schematic diagram of the overall structure of the air intake unit of the beam dose and position distribution detection system described in this embodiment of the invention;

[0036] Figure 7 This is a schematic diagram of the overall structure of the gas outlet unit of the beam dose and position distribution detection system described in this embodiment of the invention;

[0037] Figure 8 This is a schematic diagram showing the connection between multiple detectors and a pressure control device in the beam dose and position distribution detection system described in this embodiment of the invention.

[0038] In the picture:

[0039] 1. Detector; 11. Housing; 111. Airtight cavity; 112. Air inlet; 113. Air outlet; 114. Frame; 115. Panel; 1151. Window; 1152. Window plate; 11521. Frame; 11522. Window film; 1153. Support wire; 1154. Stepped recess; 12. Inner core; 121. Dosage monitoring unit; 1211. First high-voltage electrode; 12111. Wire frame; 12112. Gold-plated tungsten wire; 1212. First insulating plate; 1213. Signal electrode; 122. Position monitoring unit; 1221. Second high-voltage electrode; 1222. Second insulating plate; 1223. Segmented electrode; 12231. First signal strip; 12232. Second signal strip; 1224. Third insulating plate; 1225. Third high-voltage electrode; 123. High 1. Pressure isolation plate; 2. Air pressure control device; 21. Inflation unit; 211. Gas cylinder; 212. Inlet pipe; 213. Branch pipe; 214. First valve; 215. Inlet airflow regulating component; 2151. First ball valve; 2152. First needle valve; 216. Air pressure regulating component; 2161. Gauge pipe; 2162. Solenoid valve; 2163. Vacuum gauge; 217. Second valve; 218. Pressure reducing valve; 22. Outlet unit; 221. Outlet pipe; 222. Vacuum pump; 223. Connecting pipe; 224. Third valve; 225. Flow meter; 226. Outlet airflow regulating component; 2261. Second ball valve; 2262. Second needle valve; 227. Fourth valve; 3. Data acquisition module; 31. Charge integrating electrometer; 32. Electronics; 4. High voltage module; 5. Host computer. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0041] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the system or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., used to define components are merely for the convenience of distinguishing the aforementioned components. Unless otherwise stated, these terms have no special meaning and should not be construed as indicating or implying relative importance.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] Currently, existing particle flash radiotherapy devices can generally perform both conventional and flash radiotherapy. However, because the detectors used to monitor the beam current in conventional radiotherapy are not interchangeable with those used in flash radiotherapy, existing particle flash radiotherapy devices require two types of detectors, and the corresponding detector must be installed before each radiotherapy session depending on the type of treatment. This increases the preparation time before each radiotherapy session, thus reducing the efficiency and effectiveness of the particle flash radiotherapy device; it also increases the equipment cost. Based on this, the present invention provides a beam dose and position distribution monitoring system and method of use. By changing the internal air pressure and operating voltage of the detector, the system can switch its operating state, enabling it to be used for both monitoring the dose and position distribution of the beam current used in flash radiotherapy and monitoring the dose and position distribution of the beam current used in conventional radiotherapy.

[0044] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0045] Example 1

[0046] like Figures 1-8 As shown, this embodiment of the invention provides a beam dose and position distribution detection system, including:

[0047] Detector 1 includes a housing 11 and an inner core 12. The housing 11 has an airtight cavity 111 inside. The housing 11 has an air inlet 112 and an air outlet 113 communicating with the airtight cavity 111. The inner core 12 is disposed inside the airtight cavity 111. The inner core 12 includes a dose monitoring unit 121 and a position monitoring unit 122. The dose monitoring unit 121 and the position monitoring unit 122 are arranged front and rear along the beam injection direction and are isolated from each other.

[0048] The air pressure control device 2 includes an inflation unit 21 and an air outlet unit 22. The inflation unit 21 is connected to the air inlet 112, and the air outlet unit 22 is connected to the air outlet 113. The inflation unit 21 is used to inject working gas into the airtight cavity 111, and the air outlet unit 22 is used to discharge working gas from the airtight cavity 111. The inflation unit 21 and the air outlet unit 22 can cooperate to control the air pressure in the airtight cavity 111.

[0049] The acquisition module 3 is connected to the dose monitoring unit 121 and the position monitoring unit 122 respectively. The acquisition module 3 is used to acquire the dose signal and position distribution signal generated by the dose monitoring unit 121 and the position monitoring unit 122 when the beam passes through, and to calculate the dose and position distribution information of the beam based on the acquired signals.

[0050] High voltage module 4 is electrically connected to dose monitoring unit 121, position monitoring unit 122 and acquisition module 3 respectively to supply power to dose monitoring unit 121, position monitoring unit 122 and acquisition module 3. The output voltage value of high voltage module 4 can be set and read back through serial peripheral interface, so as to adjust the working voltage monitored by dose monitoring unit 121 and position monitoring unit 122 according to actual needs.

[0051] The host computer 5 is communicatively connected to the acquisition module 3. The acquisition module 3 can transmit the beam current information it collects and calculates to the host computer 5 for corresponding data processing and result display. The host computer 5 can communicate with the acquisition module 3 via Ethernet, WiFi, Bluetooth, or data cable.

[0052] In this embodiment, the air pressure inside the detector 1 and the working voltage of the inner core 12 can be adjusted to the values ​​required for monitoring the beam dose and position distribution, respectively, by the air pressure control device 2 and the high-voltage module 4, according to the beam type used in each radiotherapy session of the particle flash radiotherapy device. This satisfies the requirements for monitoring different types of beams. Therefore, this embodiment can be used to monitor the dose and position distribution of the beam used in flash radiotherapy as well as the dose and position distribution of the beam used in conventional radiotherapy. The particle flash radiotherapy device does not need to replace different detectors 1 for different beam types used in each radiotherapy session. This can shorten the preparation time before each radiotherapy session, thereby improving the efficiency and radiotherapy efficacy of the particle flash radiotherapy device, and also reduce the equipment cost of the particle flash radiotherapy device.

[0053] Furthermore, such as Figure 2 As shown, the housing 11 includes a frame 114 and a panel 115 with a sealing cover on both sides of the frame 114. A sealing element such as a sealing ring is also provided between the frame 114 and the panel 115 to ensure the sealing of the connection between the frame 114 and the panel 115. A window 1151 is provided on the panel 115, and a window plate 1152 for beam to be injected or ejected is fixedly covered on the window 1151.

[0054] Specifically, such as Figure 3 As shown, panel 115 has a stepped recess 1154, window 1151 is opened on the bottom surface of stepped recess 1154, window panel 1152 is fixed in stepped recess 1154 by means of adhesive or the like, and window panel 1152 includes frame 11521 and window film 11522 fixed on frame 11521.

[0055] It is understood that the shape and size of the window 1151 and the step recess 1154, as well as the material, shape, and size of the frame 11521 and the window film 11522, can be set according to actual needs, and this embodiment does not impose any restrictions on this.

[0056] Preferably, the stepped recess 1154 is a square recess with a size of 121mm×121mm~401mm×401mm and a depth of 2~3mm, the window 1151 is a circular window with a diameter of 92mm-364mm, the frame 11521 is a TU-752 plate frame with a thickness of 2~3mm, and the window film is a Kapton film with a thickness of 50~250μm.

[0057] Furthermore, a support wire 1153 is also provided on the window 1151, and several wire-passing holes are provided on the edge of the window 1151. The support wire 1153 is fixedly passed through the wire-passing holes and onto the window 1151. The support wire 1153 can be made of materials such as nylon wire, PE wire, or stainless steel wire, and its density and tension can be set according to the area of ​​the window film. When the detector 1 monitors the beam, a pressure difference exists on both sides of the window plate 1152. This pressure difference can cause the window film to deform. The support wire 1153 can support the window film, preventing excessive deformation and damage.

[0058] Because the internal air pressure of detector 1 is much lower than the ambient air pressure when monitoring the beam used in Flash radiotherapy, the window membrane 11522 will deform significantly. However, when monitoring the beam used in conventional radiotherapy, the internal air pressure of detector 1 is only slightly higher than the ambient air pressure, and the window membrane 11522 will only deform slightly. Therefore, in this embodiment, a support wire 1153 is only provided on the inner side of the window membrane 11522 to support it. Of course, in some other embodiments, a support wire 1153 can also be provided on the outer side of the window membrane 11522.

[0059] Furthermore, such as Figure 3 As shown, the dose monitoring unit 121 includes a first high-voltage electrode 1211, a first insulating plate 1212 and a signal electrode 1213 stacked in sequence. The first high-voltage electrode 1211 is electrically connected to the high-voltage module 4, and the signal electrode 1213 is connected to the acquisition module 3.

[0060] The first high-voltage electrode 1211 is a gold-plated tungsten wire electrode, including a wire frame 12111 and a plurality of gold-plated tungsten wires 12112 spaced apart on the wire frame 12111; the first insulating plate 1212 is a TU-752 plate frame with a thickness of 0.5mm to 3mm, and the dose signal electrode 1213 is a double-sided aluminum-plated polyimide film electrode with a thickness of 2μm to 25μm.

[0061] Preferably, in order to make the electric field generated by the first high-voltage plate 1211 more uniform, the gold-plated tungsten wire 12112 in this embodiment is at a 45° angle to the horizontal plane. Of course, in some other embodiments, the gold-plated tungsten wire 12112 can also be laid at other angles.

[0062] It should be noted that in some other embodiments, the first high-voltage electrode 1211, the first insulating plate 1212, and the dose signal electrode 1213 may also be made of other materials or specifications, and the present invention does not limit this.

[0063] Furthermore, the position monitoring unit 122 includes a second high-voltage electrode plate 1221, a second insulating plate 1222, a strip electrode plate 1223, a third insulating plate 1224, and a third high-voltage electrode plate 1225 stacked sequentially. The second high-voltage electrode plate 1221 and the third high-voltage electrode plate 1225 are electrically connected to the high-voltage module 4, and the strip electrode plate 1223 is connected to the acquisition module 3. The strip electrode plate 1223 has a plurality of spaced first signal bars 12231 and second signal bars 12232, which are perpendicular to each other.

[0064] Among them, the second insulating plate 1222 and the third insulating plate 1224 are TU-752 plate frames with a thickness of 0.5mm to 3mm, and the second high voltage electrode plate 1221 and the third high voltage electrode plate 1225 are gold-plated tungsten wire electrodes.

[0065] The slit electrode plate 1223 is formed by pressing together three rigid plates: a front frame plate, a slit core plate, and a rear frame plate. The front and rear frame plates are TU-752 sheet metal frames with a thickness of 0.5mm to 2mm, and the slit core plate is TU-752 sheet metal with a thickness of 0.05mm to 0.2mm. The front surface of the slit core plate has 64 to 256 horizontally arranged first signal bars 12231 with a center distance of 1mm to 2mm, and the rear surface of the slit core plate has 64 to 256 vertically arranged second signal bars 12232 with a center distance of 1mm to 2mm. The first and second signal bars 12231 and 12232 are gold-plated or immersion gold copper-clad signal bars with a copper layer thickness of 10 to 70μm and a width of 0.8 to 1.8mm.

[0066] It should be noted that in some other embodiments, the second high-voltage plate 1221, the second insulating plate 1222, the strip plate 1223, the third insulating plate 1224, and the third high-voltage plate 1225 may also be made of other materials and specifications, and the present invention does not limit them.

[0067] like Figure 3 As shown, in this embodiment, the dose monitoring unit 121 and the position monitoring unit 122 are isolated by a high-voltage isolation plate 123.

[0068] Furthermore, such as Figure 6As shown, the inflation unit 21 includes a gas cylinder 211 and an air inlet pipe 212. One end of the air inlet pipe 212 is connected to the gas cylinder 211, and the other end is connected to the air inlet 112. A branch pipe 213 is connected to the air inlet pipe 212. The branch pipe 213 is used for emergency venting or manual purging of excess gas in the air inlet pipe 212. A first valve 214 is provided on the branch pipe 213 for opening or closing the branch pipe 213. An airflow regulating component 215 and a pressure regulating component 216 are provided on the air inlet pipe 212 between the air inlet 112 and the branch pipe 213. The airflow regulating component 215 is used to regulate and control the airflow on the air inlet pipe 212, and the pressure regulating component... 216 is used to regulate and control the air pressure in the airtight cavity 111. A second valve 217 and a pressure reducing valve 218 are provided on the air inlet pipe 212 between the gas cylinder 211 and the branch pipe 213. The second valve 217 and the pressure reducing valve 218 work together to open and close the gas cylinder 211 and regulate the output air pressure of the gas cylinder 211. When the second valve 217 and the pressure reducing valve 218 work together to open the gas cylinder 211, the gas cylinder 211 can be opened first through the pressure reducing valve 218, and then the air flow rate output by the gas cylinder 211 can be finely adjusted through the second valve 217 to prevent the gas flow rate output by the gas cylinder 211 from being too large due to the pressure reducing valve 218 being opened too much, which would damage other components on the air inlet pipe 212.

[0069] The intake airflow regulating component 215 includes a first ball valve 2151 and a first needle valve 2152. When it is necessary to regulate the airflow on the intake pipe 212, the airflow on the intake pipe 212 can be coarsely adjusted to near the required airflow using the first ball valve 2151, and then finely adjusted using the first needle valve 2152, thereby precisely adjusting the airflow on the intake pipe 212 to the required airflow.

[0070] The air pressure regulating assembly 216 includes a gauge tube 2161, a solenoid valve 2162, and a vacuum gauge 2163. The gauge tube 2161 is located at the end of the air inlet pipe 212 near the air inlet 112 and is used to monitor the air pressure inside the airtight cavity 111. The solenoid valve 2162 is located on the side of the gauge tube 2161 away from the air inlet 112. The vacuum gauge 2163 is connected to both the gauge tube 2161 and the solenoid valve 2162. In this embodiment, the threshold of the vacuum gauge 2163 can be set according to the required air pressure value inside the airtight cavity 111. The vacuum gauge 2163 sends a control signal to the solenoid valve 2162 based on the difference between the actual air pressure value inside the airtight cavity 111 measured by the gauge tube 2161 and the threshold value. The solenoid valve 2162 adjusts its closure according to the received control signal, thereby adjusting the air intake of the airtight cavity 111 to regulate the air pressure value inside the airtight cavity 111 to near the threshold value and maintain stability.

[0071] Furthermore, such as Figure 7As shown, the gas outlet unit 22 includes a gas outlet pipe 221 and a vacuum pump 222. One end of the gas outlet pipe 221 is connected to the gas outlet 113. The vacuum pump 222 is connected to the gas outlet pipe 221 through a connecting pipe 223. A third valve 224 is provided on the connecting pipe 223. A flow meter 225, a gas flow regulating component 226, and a fourth valve 227 are provided on the gas outlet pipe 221. The flow meter 225 and the gas flow regulating component 226 are located between the gas outlet 113 and the connecting pipe 223. The flow meter 225 is used to monitor the gas flow rate in the airtight cavity 111. The gas flow regulating component 226 is used to regulate the gas flow rate on the gas outlet pipe 221. The fourth valve 227 is located between the connecting pipe 223 and the other end of the gas outlet 113. The vacuum pump 222 can cooperate with the third valve 224 and the fourth valve 227 to remove the gas in the airtight cavity 111.

[0072] The airflow regulating component 226 includes a second ball valve 2261 and a second needle valve 2262. When it is necessary to regulate the airflow on the air outlet pipe 221, the airflow on the air outlet pipe 221 can be coarsely adjusted to near the required airflow using the second ball valve 2261, and then finely adjusted using the second needle valve 2262, thereby precisely adjusting the airflow on the air outlet pipe 221 to the required airflow.

[0073] It should be pointed out that, as Figure 8 As shown, when multiple detectors 1 are provided in some embodiments to improve safety, the multiple detectors 1 can be connected in series through the air inlet 112 and air outlet 113 of the detector 1, and the multiple detectors 1 connected in series can be connected to a set of air pressure control devices 2 respectively, so as to save equipment costs.

[0074] Furthermore, the acquisition module 3 includes a charge integrating electrometer 31 and electronics 32. The charge integrating electrometer 31 is connected to the dose monitoring unit 121, and the electronics 32 is connected to both the position monitoring unit 122 and the charge integrating electrometer 31. The charge integrating electrometer 31 is connected to the dose signal plate 1213 of the dose monitoring unit 121 to acquire the dose signal generated by the dose signal plate 1213. After acquiring the dose signal, the charge integrating electrometer 31 can convert the dose signal into a signal that can be acquired by the electronics 32 through pre-amplification and waveform conversion. The electronics 32 is connected to the strip plate 1223 of the position monitoring unit 122 to acquire the beam position distribution signal generated by the strip plate 1223. The electronics 32 can calculate the dose and position distribution information of the beam based on the acquired dose signal and position distribution signal, and transmit this data to the host computer 5 for corresponding data processing and result display.

[0075] Specifically, the electronics 32 in this embodiment employs multi-channel integrated electronics, which includes a front-end readout dedicated integrated chip (ASIC) and a field-programmable gate array (FPGA). The FPGA controls the ASIC to convert multi-channel signals into digital signals and uploads them to the host computer 5 via a remote transmission protocol. Additionally, the charge integrating electrometer 31 converts weak current signals into voltage signals (I / V conversion), then converts the voltage signals into digital signals via an analog-to-digital converter (ADC) and transmits them to the multi-channel integrated electronics 32 for signal acquisition via signal lines or other means.

[0076] It should be noted that, considering installation issues, in this embodiment, the detector 1 and the acquisition module 3 can be separated and connected by a cable, or the detector 1 and the acquisition module 3 can be combined into one unit and connected by connecting elements such as a rigid-flexible bonding plate.

[0077] It is understood that in some other embodiments, other types of acquisition instruments may also be used to acquire the signals generated by the dose monitoring unit 121 and the position monitoring unit 122, and the present invention does not limit this.

[0078] Example 2

[0079] This invention provides a method for monitoring the conventional beam current using the beam dose and position distribution monitoring system provided in Embodiment 1 during conventional radiotherapy in a particle flash radiotherapy device, specifically including the following steps:

[0080] Step 1: Install detector 1 on the terminal frame of the particle flash radiotherapy device;

[0081] Step 2: Inject the corresponding working gas into the airtight cavity 111 through the air pressure control device 2 and adjust the air pressure in the airtight cavity 111 to near the air pressure value required for monitoring the conventional beam.

[0082] The working gas is nitrogen, and the method for adjusting the gas pressure inside the airtight chamber 111 by the gas pressure control device 2 is as follows:

[0083] (1) Close the first valve 214, the second valve 217, the pressure reducing valve 218 and the fourth valve 227;

[0084] (2) Set the threshold of vacuum gauge 2163, start vacuum pump 222, adjust the outflow regulating component 226, and slowly extract the gas from detector 1 until the internal gas pressure of detector 1 reaches 10. -5 Around mbar;

[0085] (3) Set the threshold of vacuum gauge 2163 to about 10 mbar higher than the ambient air pressure;

[0086] (4) Turn off vacuum pump 222, open second valve 217 and pressure reducing valve 218 to adjust the output gas pressure of gas cylinder 211 to about 0.1-0.4 MPa;

[0087] (5) Adjust the air flow rate of the inlet pipe 212 and the outlet pipe 221 by adjusting the air flow rate of the inlet air flow regulating component 215 and the outlet air flow regulating component 226 so that the air flow rate inside the airtight cavity 111 is 20-30 sccm.

[0088] Step 3: Connect the power supply to the acquisition module 3 and the high voltage module 4, and set the output voltage of the high voltage module 4 to 300V;

[0089] Step 4: Control the particle flash radiotherapy device to release the beam;

[0090] Step 5: Acquisition module 3 acquires the dose signal and position signal generated by dose monitoring unit 121 and position monitoring unit 122 when the beam passes through detector 1. Acquisition module 3 calculates the dose and position distribution information of the beam based on the acquired dose signal and position distribution signal and transmits it to host computer 5. Host computer 5 performs corresponding data processing and displays the results of the dose and position distribution information of the beam transmitted by acquisition module 3.

[0091] Step Six: After the radiotherapy is completed, turn off all power.

[0092] Example 3

[0093] This invention provides a method for monitoring the flash beam using the beam dose and position distribution monitoring system provided in Embodiment 1 during flash radiotherapy in a particle flash radiotherapy device, specifically including the following steps:

[0094] Step 1: Install detector 1 on the terminal frame of the particle flash radiotherapy device;

[0095] Step 2: Inject the corresponding working gas into the airtight cavity 111 through the air pressure control device 2 and adjust the air pressure in the airtight cavity 111 to near the air pressure value required for monitoring the Flash beam;

[0096] In step two, the working gas injected into the airtight cavity 111 consists of 80% argon and 20% carbon dioxide. The method by which the pressure control device 2 adjusts the pressure inside the airtight cavity 111 is as follows:

[0097] (1) Close the first valve 214, the second valve 217, the pressure reducing valve 218 and the fourth valve 227;

[0098] (2) Set the threshold of vacuum gauge 2163, start vacuum pump 222, adjust the outflow regulating component 226, and slowly extract the gas from detector 1 until the internal gas pressure of detector 1 reaches 10. -5 Around mbar;

[0099] (3) Set the threshold of vacuum gauge 2163, open the second valve 217 and pressure reducing valve 218 to adjust the output gas pressure of gas cylinder 211, adjust the inlet airflow regulating component 215 to slowly introduce working gas into the airtight cavity 111, and continuously adjust the inlet airflow regulating component 215 and the outlet airflow regulating component 226 until the inlet and outlet airflow reach a dynamic balance and the internal gas pressure of detector 1 is dynamically stabilized at 10. -2 Near MBR;

[0100] Step 3: Connect the power supply to the acquisition module 3 and the high voltage module 4, and set the output voltage of the high voltage module 4 to 30V;

[0101] Step 4: Control the particle flash radiotherapy device to release the beam;

[0102] Step 5: Acquisition module 3 acquires the dose signal and position distribution signal generated by dose monitoring unit 121 and position monitoring unit 122 when the beam passes through detector 1. Acquisition module 3 calculates the dose and position distribution information of the beam based on the acquired dose and position distribution signals and transmits it to host computer 5. Host computer 5 performs corresponding data processing and displays the results of the dose and position distribution information of the beam transmitted by acquisition module 3.

[0103] Step 6: After radiotherapy, turn off the power to the acquisition module 3 and the high-voltage module 4, and restore the internal air pressure of the detector 1 to near the ambient air pressure through the air pressure control device 2. After the internal air pressure of the detector 1 stabilizes, turn off all power.

[0104] The method for restoring the internal air pressure of detector 1 to near the ambient air pressure in step six is ​​as follows:

[0105] (1) Close the first valve 214, vacuum pump 222, third valve 224 and fourth valve 227;

[0106] (2) Set the threshold of vacuum gauge 2163, adjust the output gas pressure of gas cylinder 211 and the air intake airflow regulating component 215 to slowly inject gas into airtight cavity 111 until the internal gas pressure of detector 1 reaches near the ambient gas pressure.

[0107] It is understood that in this embodiment, when the gas in the airtight cavity 111 is extracted and the internal air pressure of the detector 1 is restored to the ambient air pressure, the gas in the detector 1 can be extracted or injected into the detector 1 in multiple times by setting the threshold of the vacuum gauge 2163 multiple times, so as to prevent the window film of the detector 1 from being damaged due to excessively fast extraction or injection of gas.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A beam dose and position distribution monitoring system, characterized in that, include: The detector (1) includes a housing (11) and an inner core (12). The housing (11) has an airtight cavity (111) inside. The housing (11) has an air inlet (112) and an air outlet (113) communicating with the airtight cavity (111). The inner core (12) is disposed inside the airtight cavity (111). The inner core (12) includes a dose monitoring unit (121) and a position monitoring unit (122). The dose monitoring unit (121) and the position monitoring unit (122) are arranged front and rear along the beam injection direction and are isolated from each other. A pressure control device (2) includes an inflation unit (21) and an exhaust unit (22). The inflation unit (21) is connected to the air inlet (112), and the exhaust unit (22) is connected to the air outlet (113). The inflation unit (21) is used to inject working gas into the airtight cavity (111), and the exhaust unit (22) is used to discharge the working gas from the airtight cavity (111). The inflation unit (21) and the exhaust unit (22) cooperate to control the pressure in the airtight cavity (111). The inflation unit (21) includes a gas cylinder (2). 11) and an air inlet pipe (212), one end of which is connected to the gas cylinder (211), and the other end of which is connected to the air inlet (112). A branch pipe (213) is connected to the air inlet pipe (212), and a first valve (214) is provided on the branch pipe (213). An airflow regulating component (215) and a pressure regulating component (216) are provided on the air inlet pipe (212) between the air inlet (112) and the branch pipe (213). A second valve (214) is provided on the air inlet pipe (212) between the branch pipe (213) and the gas cylinder (211). 17) and pressure reducing valve (218); the air pressure regulating assembly (216) includes a gauge tube (2161), a solenoid valve (2162) and a vacuum gauge (2163), the gauge tube (2161) is located at the end of the air inlet pipe (212) near the air inlet (112), the solenoid valve (2162) is located on the side of the gauge tube (2161) away from the air inlet (112), and the vacuum gauge (2163) is connected to the gauge tube (2161) and the solenoid valve (2162) respectively; the air outlet unit (22) includes an air outlet pipe (221) and a vacuum pump (222), the air outlet pipe (221) One end is connected to the air outlet (113), and the vacuum pump (222) is connected to the air outlet pipe (221) through the connecting pipe (223). A third valve (224) is provided on the connecting pipe (223), and a flow meter (225), an air flow regulating component (226), and a fourth valve (227) are provided on the air outlet pipe (221). The flow meter (225) and the air flow regulating component (226) are located between the air outlet (113) and the connecting pipe (223), and the fourth valve (227) is located between the connecting pipe (223) and the other end of the air outlet pipe (221). The acquisition module (3) is connected to the dose monitoring unit (121) and the position monitoring unit (122) respectively; A high-voltage module (4) is electrically connected to the dose monitoring unit (121) and the position monitoring unit (122) respectively, and is used to provide operating voltage to the dose monitoring unit (121) and the position monitoring unit (122); wherein, the dose monitoring unit (121) includes a first high-voltage electrode plate (1211), a first insulating plate (1212) and a signal electrode plate (1213) stacked in sequence, the first high-voltage electrode plate (1211) includes a wire frame (12111), the wire frame (12111) The position monitoring unit (122) has several gold-plated tungsten wires (12112) arranged at intervals. The position monitoring unit (122) includes a second high-voltage electrode plate (1221), a second insulating plate (1222), a strip electrode plate (1223), a third insulating plate (1224), and a third high-voltage electrode plate (1225) stacked in sequence. The strip electrode plate (1223) has several first signal bars (12231) and second signal bars (12232) arranged at intervals. The first signal bars (12231) and the second signal bars (12232) are perpendicular to each other. The host computer (5) is communicatively connected to the acquisition module (3).

2. The beam dose and location distribution monitoring system as described in claim 1, characterized in that, The housing (11) includes a frame (114) and a panel (115) sealed on both sides of the frame (114). The panel (115) has a window (1151) and a window plate (1152) for beam to enter or exit is fixedly covered on the window (1151).

3. The beam dose and location distribution monitoring system as described in claim 2, characterized in that, A support wire (1153) is also provided on the window (1151), and the support wire (1153) supports the window panel (1152) on one or both sides.

4. The beam dose and location distribution monitoring system as described in claim 1, characterized in that, The acquisition module (3) includes a charge integrating electrometer (31) and electronics (32). The charge integrating electrometer (31) is connected to the dose monitoring unit (121), and the electronics (32) is connected to the position monitoring unit (122) and the charge integrating electrometer (31).

5. The method of using the beam dose and position distribution monitoring system as described in any one of claims 1-4, characterized in that, Includes the following steps: The detector (1) is installed on the terminal frame of the particle flash radiotherapy device; According to the type of radiotherapy, the corresponding working gas is injected into the airtight cavity (111) through the air pressure control device (2) and the air pressure in the airtight cavity (111) is adjusted to near the air pressure value required for monitoring the beam used in radiotherapy; Connect the power supply to the acquisition module (3) and the high voltage module (4), and set the output voltage of the high voltage module (4) to the required operating voltage of the dose monitoring unit (121) and the position monitoring unit (122); Control the particle Flash radiotherapy device to perform beam firing; The acquisition module (3) acquires the dose signal and position signal generated by the dose monitoring unit (121) and the position monitoring unit (122) when the beam passes through the detector (1). The acquisition module (3) calculates the dose and position distribution information of the beam based on the acquired dose and position signals and transmits it to the host computer (5). The host computer (5) performs corresponding data processing and displays the results of the dose and position distribution information of the beam transmitted by the acquisition module (3). After radiotherapy, the power supply to the acquisition module (3) and the high-pressure module (4) is turned off. The internal air pressure of the detector (1) is restored to near the ambient air pressure by the air pressure control device (2). After the internal air pressure of the detector (1) stabilizes, all power supplies are turned off.

Images