Integrated depth dose curve measurement device and method for proton therapy

Abstract

The present invention discloses an integrated depth dose curve measurement device and method for proton therapy. The measurement device can provide an accurate and convenient measurement solution for measuring the IDD curve of a proton beam. It can be conveniently connected to an external ionization chamber and a guide rail system to measure the IDD curve of a medical proton beam. During the measurement process, the high-voltage state of the ionization chamber and the position of the guide rail can be detected in real time. The modular design facilitates equipment maintenance by users and future replacement and upgrading of some modules. Moreover, the measurement device can accurately measure the current signal output by the ionization chamber, and its overall noise is below 60pA, providing precise ionization chamber output data for the position resolution requirements of subsequent IDD curves.

Description

Technical Field

[0001] The present invention relates to the field of weak charge acquisition, and in particular to an integrated depth dose curve measurement device and method for proton therapy. Background Art

[0002] Proton therapy is an emerging radiotherapy method for tumors, offering significant advantages over conventional photon radiotherapy. Proton therapy utilizes a unique Bragg peak to concentrate the radiation dose within the target area, reducing damage to healthy tissue and the risk of secondary primary cancers. Proton therapy is considered a key development direction in radiotherapy both domestically and internationally. Recent research has revealed that proton therapy not only offers the physical advantages of high-dose deposition at the Bragg peak but also offers radiobiological advantages derived from high dose rates. These inherent advantages have earned proton therapy broad prospects for development both domestically and internationally.

[0003] The proton therapy system itself is a complex and sophisticated system, and its use in clinical tumor radiotherapy requires stringent safety assurance. To ensure the proper functioning of the proton therapy device and the generation of data with the required accuracy, every proton therapy center must establish a regular quality assurance (QA) system and utilize appropriate QA equipment to measure proton therapy system performance parameters, ensuring that performance remains within reasonable tolerances and meets established quality requirements. This dedicated QA equipment is crucial for ensuring treatment accuracy, medical radiation safety, and the stable operation of the entire proton therapy center.

[0004] Currently, the devices used internationally to measure proton IDD curves include the Blue Phantom2 and Zebra from the Belgian IBA company, and the MP3-P and MP3-PL Water Phantoms from the German PTW company. However, these devices are usually expensive and need to be used in conjunction with other supporting equipment. The measurement equipment cannot be purchased separately.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The purpose of the present invention is to provide an integrated depth dose curve measurement device and method for proton therapy, which can be conveniently connected to a medical ionization chamber detector, accurately measure the integrated depth dose (IDD) curve of a medical proton beam, and reduce the cost of use.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] An integrated depth dose curve measurement device for proton therapy comprises: a front-end amplifier module, a high-voltage module, an ADC acquisition module, a communication interface, an ARM central processing module, and a motor control and drive module; the front-end amplifier module is connected to the ADC acquisition module, the ADC acquisition module, the high-voltage module, and the motor control and drive module are each connected to the ARM central processing module; the ARM central processing module is connected to an external computer via the communication interface;

[0009] The ARM central processing module controls the high-voltage module to apply voltage to the ionization chamber according to the commands issued by the computer, controls the position of the ionization chamber by controlling the motor control drive module, and then controls the ionization chamber signal by controlling the ADC acquisition module and transmits it to the computer. The computer completes the integrated depth dose curve measurement based on the received ionization chamber signal.

[0010] A method for measuring an integrated depth dose curve for proton therapy is implemented based on the aforementioned measurement device, comprising the following steps:

[0011] Step 1: Connect the main ionization chamber, reference ionization chamber, and guide rail motor to the measuring equipment respectively, and turn on the power of the measuring equipment;

[0012] Step 2: Send an initialization command via the computer, and the ARM central processing module initializes the measuring device, including:

[0013] Step 3: The computer issues a status detection command, and the ARM central processing module sends the voltage value applied by the high-voltage module and the position of the main ionization chamber controlled by the motor control drive module through the guide motor to the computer to determine whether the measuring device is in normal working condition;

[0014] Step 4: In the absence of beam current, the computer issues a data acquisition command, and the ARM central processing module and the ADC acquisition module respectively measure the background noise of the two ionization chambers and upload the data to the computer.

[0015] Step 5: Under the specified beam energy, the computer sends parameter setting commands, and the ARM central processing module sets the movement range of the main ionization chamber in the water tank and the movement step size of the guide motor;

[0016] Step 6: The computer issues a measurement command, and the ARM central processing module controls the motor control drive module to drive the guide motor to move the main ionization chamber to the specified position. The two ADC acquisition modules each collect the corresponding ionization chamber signal and upload it to the computer. The computer combines the ionization chamber signal with the corresponding ionization chamber background noise to obtain the integrated depth dose curve measurement result at the specified beam energy and the specified position.

[0017] Step 7: Based on step 6, measurements are performed at different positions within the set moving range using the set moving step length of the guide motor to obtain an integrated depth dose curve measurement result for the moving step length within the set moving range at the specified beam energy;

[0018] Step 8: Change the beam energy and repeat steps 6 and 7 to obtain the integrated depth dose curve measurement results of the moving step within the set moving range under different beam energies.

[0019] It can be seen from the technical solution provided by the present invention that the measuring device can provide an accurate and convenient measurement solution for measuring the IDD curve of a proton beam. It can be conveniently connected to an external ionization chamber and a guide rail system to measure the IDD curve of a medical proton beam. During the measurement process, the high-voltage state of the ionization chamber and the position of the guide rail can be detected in real time. The modular design facilitates equipment maintenance and future replacement and upgrading of some modules by users; and greatly reduces the cost of the measuring equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 A schematic diagram of an integrated depth dose curve measurement device for proton therapy provided by an embodiment of the present invention;

[0022] Figure 2 An operation flow chart of an integrated depth dose curve measurement device for proton therapy provided by an embodiment of the present invention;

[0023] Figure 3 A schematic diagram of a front-end amplifier module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following is a clear and complete description of the technical solutions in the embodiments of the present invention, in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] First, the following terms may be used in this article:

[0026] The terms "include," "comprises," "contains," "has," or other similar expressions should be interpreted as non-exclusive. For example, "including certain technical features (such as raw materials, components, ingredients, carriers, dosage forms, materials, dimensions, parts, components, mechanisms, devices, steps, procedures, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products, or manufactured articles, etc.) should be interpreted as including not only the technical features explicitly listed, but also other technical features known in the art that are not explicitly listed.

[0027] The term "consisting of" excludes any technical features not explicitly listed. If used in a claim, this term renders the claim closed, excluding any technical features other than those explicitly listed, except for conventional impurities associated with them. If this term appears only in a clause of a claim, it limits only the elements explicitly listed in that clause; elements listed in other clauses are not excluded from the claim as a whole.

[0028] Unless otherwise specified or limited, the terms "connected" and "connection" should be understood broadly. For example, they can refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this document based on specific circumstances.

[0029] When a dimension or other parameter is expressed in the form of a numerical range, the numerical range should be understood to specifically disclose all ranges formed by the pairing of any upper limit, lower limit, or preferred value within the numerical range, regardless of whether the range is explicitly stated. For example, if a numerical range of "2 to 8" is stated, the numerical range should be interpreted as including ranges of "2 to 7," "2 to 6," "5 to 7," "3 to 4 and 6 to 7," "3 to 5 and 7," "2 and 5 to 7," etc. Unless otherwise specified, the numerical ranges stated herein include both their end values ​​and all integers and fractions within the numerical range.

[0030] The following describes in detail the integrated depth dose curve measurement device and method for proton therapy provided by the present invention. Any information not described in detail in the examples of the present invention represents prior art known to those skilled in the art. For any conditions not specified in the examples of the present invention, the procedures were performed according to conventional conditions in the art or the manufacturer's recommended conditions. Instruments used in the examples of the present invention, where the manufacturer is not specified, are all commercially available conventional products.

[0031] Example 1

[0032] The embodiment of the present invention provides an integrated depth dose curve measurement device (hereinafter referred to as an electronic device) for proton therapy, which can be conveniently connected to a medical ionization chamber detector to accurately measure the IDD curve of a medical proton beam. Figure 1 As shown, it mainly includes: a front-end amplifier module, a high-voltage module, an ADC (analog-to-digital converter) acquisition module, a communication interface, an ARM central processing module and a motor control drive module; the front-end amplifier module is connected to the ADC acquisition module, and the ADC acquisition module, the high-voltage module and the motor control drive module are respectively connected to the ARM central processing module; the ARM central processing module is connected to an external computer through the communication interface; as an example, the communication method between the ARM central processing module and the computer can be the UDP protocol (User Datagram Protocol);

[0033] The ARM central processing module, based on commands from the computer, controls the high-voltage module to apply voltage to the ionization chamber, controls the position of the ionization chamber by controlling the motor control drive module, and then controls the ionization chamber signal by controlling the ADC acquisition module. The signal is then transmitted to the computer, which then completes the integrated depth dose curve measurement based on the received ionization chamber signal. Specifically, during the measurement process, the motor drive module is responsible for controlling the movement of the guide rails in the water tank and detecting their position; the ARM central processing unit is responsible for controlling each module and interacting with the computer; the ADC acquisition module is responsible for collecting the output signal of the front-end amplifier circuit and transmitting the obtained value to the ARM central processing module; the high-voltage module provides the operating high voltage for the two externally connected ionization chambers and detects the high voltage state; and the front-end amplifier module is responsible for amplifying the weak current signal output by the ionization chamber to a voltage signal that can be sampled by the ADC.

[0034] In the embodiment of the present invention, the computer is loaded with supporting software for issuing commands and completing the integrated depth dose curve measurement in combination with the information fed back by the ARM central processing module.

[0035] See also Figure 1 The front-end amplifier modules and ADC acquisition modules are each two in number, connected one-to-one. There are two ionization chambers: one main ionization chamber and the other reference ionization chamber. Both ionization chambers are energized by a high-voltage module and independently connected to a front-end amplifier module. The main ionization chamber is placed in a water tank and is driven by a guide motor driven by a motor control drive module. During measurement, the ARM central processing module transmits the ionization chamber signals collected by the two ADC acquisition modules to a computer, which then completes the integrated depth dose curve measurement based on the received ionization chamber signals.

[0036] In an embodiment of the present invention, the ARM central processing module controls the high-voltage module to apply voltage to the ionization chamber according to a command issued by the computer, controls the position of the ionization chamber by controlling the motor control drive module, and then controls the ionization chamber signal by controlling the ADC acquisition module and transmits it to the computer. The computer completes the integrated depth dose curve measurement based on the received ionization chamber signal, including:

[0037] 1) The ARM central processing module initializes the measuring device according to the initialization command issued by the computer.

[0038] 2) The ARM central processing module sends the voltage value applied by the high-voltage module and the position of the main ionization chamber controlled by the motor control drive module through the guide motor to the computer according to the status detection command issued by the computer to determine whether the measuring equipment is in normal working state.

[0039] 3) In the absence of a beam current, the ARM central processing module measures the noise floor of each ionization chamber according to a data acquisition command issued by the computer and uploads the data to the computer. Specifically, the current values ​​of the two ionization chambers can be measured at a fixed frequency to obtain the noise floor values ​​of each ionization chamber.

[0040] 4) Under the application of the specified beam energy, the ARM central processing module sets the movement range of the main ionization chamber in the water tank and the movement step size of the guide motor according to the parameter setting command issued by the computer.

[0041] 5) The ARM central processing module drives the guide rail motor through the motor control drive module according to the measurement command issued by the computer, and drives the main ionization chamber to move to the specified position. The two ADC acquisition modules respectively collect corresponding ionization chamber signals and upload them to the computer. The computer combines the ionization chamber signals with the corresponding ionization chamber background noise to obtain the integrated depth dose curve measurement results at the specified position under the specified beam energy; according to the set movement step size of the guide rail motor, measurements are performed at different positions within the set movement range to obtain the integrated depth dose curve measurement results of the movement step size within the set movement range under the specified beam energy.

[0042] 6) By applying different beam energies and issuing parameter setting commands and measurement commands through the computer, the integrated depth dose curve measurement results of the moving step within the set moving range under different beam energies are finally obtained.

[0043] In order to more clearly demonstrate the technical solution and technical effects provided by the present invention, the specific operation process of the above-mentioned measuring equipment is introduced below. Figure 2 The following is the operating procedure for measuring the IDD curve using the measuring equipment, which mainly includes:

[0044] Step A: Connect the main ionization chamber, reference ionization chamber, and guide rail motor to the electronics system, and connect the electronics system to the computer via a network cable. Place the test water tank, place the reference ionization chamber in front of it, and the main ionization chamber in the guide rail within the tank. Once all components are in place, turn on the power.

[0045] In this step, the external interface of the measuring equipment is the TRB interface, and the connecting line uses a triaxial cable, which has better shielding interference ability and ensures that the weak current signal of the ionization chamber will not be affected by spatial noise during transmission.

[0046] Step B: The measuring device initializes all devices according to the commands issued by the computer, including: high voltage control of the ionization chamber and control of the guide motor. Specifically, the guide motor moves to the test origin and high voltage is applied to the two ionization chambers so that the ionization chambers operate in the saturation zone.

[0047] In this step, the high voltage applied to the ionization chamber should meet the requirements of the working plateau parameters of the ionization chamber itself. The electronics system provides a continuously adjustable high voltage output of 0 to +200V for general medical ionization chambers, and the output high voltage is stable. The way to apply high voltage is to use the virtual short of the operational amplifier so that the amplifier as a whole works at high voltage. Its positive phase terminal is connected to high voltage, and the negative phase terminal also provides working high voltage for the connected ionization chamber under the virtual short. In this way, the middle layer and the innermost layer of the three coaxial cable are both loaded with high voltage, and the outermost layer is connected to the real earth. It can effectively reduce spatial noise interference. Since the front-end amplifier circuit as a whole works at high voltage, it is necessary to use an isolation amplifier module to isolate the signal from the high voltage and output it to the reference level of general work, which is convenient for subsequent ADC sampling and ARM central processing unit control. Therefore, the entire front-end amplifier module is composed of a front-end amplifier circuit and an isolation amplifier circuit.

[0048] like Figure 3 As shown, an example of a front-end amplifier module is provided, which mainly includes: an amplifier, a resistor R and a capacitor C; the positive input terminal of the amplifier is grounded (GND), the reverse input terminal is connected to the ionization chamber current signal I, the resistor R and the capacitor C are connected in parallel between the reverse input terminal and the output terminal of the amplifier, respectively, and the output terminal of the amplifier outputs the amplified voltage signal V.

[0049] Step C: After receiving the status detection command from the computer, the measuring device transmits the high voltage value applied by the ionization chamber and the position of the guide rail motor to the computer to confirm that all devices have completed work preparation.

[0050] The above process is a necessary step for all measurements. It ensures that the ionization chamber and guideway motor are in normal working condition, providing a foundation for the accuracy of subsequent IDD curve measurements. The ARM central processing unit continuously monitors the high voltage status and guideway position, and feeds back the status to the computer after receiving query commands.

[0051] Step D: In the absence of beam current, perform a long-term background noise test on the signals of the two ionization chambers. The test time is user-defined. The measurement equipment samples the two ionization chamber channels according to the data acquisition command issued by the computer, and then performs average filtering to obtain the background noise values ​​of the two ionization chambers. The noise values ​​are displayed graphically on the computer.

[0052] The noise floor value in this step is the combined noise of the ionization chamber, measurement equipment, and transmission cables. In subsequent IDD curve tests, the noise floor values ​​of each channel must be deducted before calculation. Ideally, when no beam current is applied, the ionization chamber output current is zero, and the output of the amplifier circuit should also be zero. In practice, due to leakage current in the ionization chamber, the noise shielding capability of the cable, the influence of the components used in the amplifier circuit itself, and printed circuit board manufacturing factors, the output of the amplifier circuit cannot be guaranteed to be zero. This introduces errors in subsequent measurements and affects measurement accuracy, necessitating initial measurement and error elimination. The influence of the ionization chamber and cables is beyond the controllable scope of the present invention, so the invention primarily considers the noise of the front-end amplifier module. The front-end amplifier circuit uses transimpedance amplification to amplify the ionization chamber's nanoampere (nA) current signal to a mV (millivolt) signal that can be sampled by the ADC module. To minimize the impact of the components themselves, the amplifier can be selected from TI's LMP7721, a high-impedance amplifier with an extremely low bias current of 26fA. Since the feedback resistor used in the transimpedance amplifier is above MΩ (megaohm), its thermal noise is also very large. The calculation formula is: Where R is the resistance value; k is the Boltzmann constant; T is the thermodynamic temperature; and B is the frequency bandwidth. Due to the randomness of various influencing factors, the noise floor value is not fixed and is significantly affected by the spatial 50 / 60 Hz frequency. Multiple ADC sampling and filtering are required to obtain a relatively accurate noise floor value. In an embodiment of the present invention, the ADC used in the ADC sampling module can be TI's ADS1219, a 24-bit ∑-Δ ADC, where Δ represents increment and ∑ represents integration or summation, with a maximum sampling rate of 1 ksps (kilosamples per second). In the ARM control logic, the ADC is sampled multiple times (for example, 64 times) for each computer read command, and the data is uploaded to the computer after averaging and filtering. In a laboratory test using an IBA Stingray ionization chamber as the main ionization chamber and a Stealth ionization chamber as the reference ionization chamber, the absolute value of the noise floor equivalent current is below 60 pA (picoamperes).

[0053] The above steps A to D are the preparatory operations required for the proton beam full energy level IDD curve test, including equipment connection and software and measurement equipment initialization.

[0054] Step E: Adjust the beam energy to the energy to be measured, and set the computer software to set the starting and ending movement points of the main ionization chamber to be tested in the water tank at this energy level (set the starting length), and set the distance between each movement of the guide rail (set the step length).

[0055] This step specifically involves setting the starting and ending points for the measurement. This is because the Bragg peaks of proton beams of different energies vary significantly. Using a uniform measurement range would result in large plateaus, which would be useless for subsequent analysis. Therefore, only the plateau data from the distance immediately preceding the Bragg peak to the distance immediately following the Bragg peak is required. This setting must be done manually for different proton beam energies. Changing the guide motor's travel distance can improve the test curve's accuracy. It's generally set to less than 1mm, with a minimum of 0.1mm. However, this depends on the guide motor's motion accuracy. A smaller travel distance allows for more test points between the starting and ending points, resulting in a more accurate IDD curve. This relies on command interaction between the ARM control module in the measurement device and the accompanying computer software. Furthermore, the guide motor has an internal position sensor, which collects position information and provides it to the motor control driver module.

[0056] Step F: Single Data Read + Motor Movement. The electronics system receives computer commands, moves the main ionization chamber to a designated position in the water tank, and reads the signals from both chambers. Finally, the data is uploaded to the computer, and the IDD curve is generated in the software.

[0057] In this step, the specific implementation process is as follows: After receiving the computer's command, the ARM central processing module moves the guide rail to the desired measurement position. The ADC sampling module then simultaneously reads the signals from both ionization chambers. The ARM central processing module performs multiple (for example, 64) average filtering operations before transmitting the data at that point to the computer. After receiving the data, the computer subtracts the ionization chamber signal from the corresponding ionization chamber noise floor. The resulting two ionization chamber signals are then compared to form an IDD curve, which is then plotted in the software. This step represents the coordinated operation of the various modules in the measurement device.

[0058] Step G: Repeat step F to obtain an IDD curve of the set beam energy within a given starting length and a set step length, and save the data file.

[0059] In this step, the IDD curve of one energy level is completely measured. The measured curve range is set by the computer software, and the distance accuracy is determined by the size of the moving distance set by the computer software.

[0060] Step H: Repeat steps E, F, and G in sequence to obtain the IDD diagram and corresponding data of each energy level within the specified beam energy range.

[0061] For example, the present invention can measure beam energies ranging from 70MeV to 245MeV. When measuring IDD curves for all energy levels, the energy levels are typically divided into 10MeV steps, but the specific energy level depends on the treatment requirements. After testing all energy data, post-processing can be performed on a computer, and the IDD curves for all energies can be plotted on a single graph, facilitating selection of the appropriate energy and Bragg peak position.

[0062] The above steps E to H are the operating steps for actually measuring the IDD curve. In this part of the process, each functional module of the device plays its irreplaceable role.

[0063] Step I: Reduce the high voltage of the ionization chamber and move the guide rail to the origin position, and issue the status command again to confirm that the high voltage and guide rail have been restored.

[0064] This step is to ensure the safety of use, confirm that the high voltage has dropped, and prevent the high voltage from affecting the safety of the user.

[0065] Step J: Turn off all power supplies, disassemble the devices connected to the cables, and recycle and store the cables and devices.

[0066] Steps I through J above involve the recovery of all equipment after testing. Because high voltage is used, it is important to ensure that it is manually reduced. Failure to do so could compromise user safety or damage the components within the measuring equipment. Equipment recovery and storage are essential to ensure the lifespan and accuracy of the equipment and should be stored as directed.

[0067] The above solution provided by the embodiment of the present invention has the following advantages:

[0068] (1) The measuring device of the present invention can accurately measure the current signal output by the ionization chamber, and its overall noise is below 60pA, providing accurate ionization chamber output data for the position resolution requirements of the subsequent IDD curve.

[0069] (2) The external interface and amplifying circuit provided by the measuring device of the present invention both use the best anti-shielding performance, and the TRB interface and high-voltage protection reduce external interference to a minimum.

[0070] (3) The measuring device of the present invention adopts a modular design, which facilitates the user's maintenance and upgrade.

[0071] (4) The measuring device of the present invention is easy to use and can measure dual-channel data simultaneously. When used in conjunction with a matching host computer, it can conveniently measure the IDD curve of a medical proton beam within a specified beam energy range (70 MeV-245 MeV).

[0072] Example 2

[0073] The present invention also provides a method for measuring an integrated depth dose curve for proton therapy, which mainly uses the measurement device provided in the above embodiment to measure the integrated depth dose curve. The method mainly includes the following steps:

[0074] Step 1: Connect the main ionization chamber, reference ionization chamber, and guide rail motor to the measuring equipment respectively, and turn on the power of the measuring equipment;

[0075] Step 2: Send an initialization command via the computer, and the ARM central processing module initializes the measuring device, including:

[0076] Step 3: The computer issues a status detection command, and the ARM central processing module sends the voltage value applied by the high-voltage module and the position of the main ionization chamber controlled by the motor control drive module through the guide motor to the computer to determine whether the measuring device is in normal working condition;

[0077] Step 4: In the absence of beam current, the computer issues a data acquisition command, and the ARM central processing module and the ADC acquisition module respectively measure the background noise of the two ionization chambers and upload the data to the computer.

[0078] Step 5: Under the specified beam energy, the computer sends parameter setting commands, and the ARM central processing module sets the movement range of the main ionization chamber in the water tank and the movement step size of the guide motor;

[0079] Step 6: The computer issues a measurement command, and the ARM central processing module controls the motor control drive module to drive the guide motor to move the main ionization chamber to the specified position. The two ADC acquisition modules each collect the corresponding ionization chamber signal and upload it to the computer. The computer combines the ionization chamber signal with the corresponding ionization chamber background noise to obtain the integrated depth dose curve measurement result at the specified beam energy and the specified position.

[0080] Step 7: Based on step 6, measurements are performed at different positions within the set moving range using the set moving step length of the guide motor to obtain an integrated depth dose curve measurement result for the moving step length within the set moving range at the specified beam energy;

[0081] Step 8: Change the beam energy and repeat steps 6 and 7 to obtain the integrated depth dose curve measurement results of the moving step within the set moving range under different beam energies.

[0082] Considering that this method is implemented based on the measuring device provided in the aforementioned embodiment, the specific details have been described in detail in the introduction of the measuring device, so they will not be repeated here.

[0083] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. An integrated depth dose curve measurement device for proton therapy, characterized in that: include: Front-end amplifier module, high-voltage module, ADC acquisition module, communication interface, ARM central processing module and motor control drive module; the front-end amplifier module is connected to the ADC acquisition module, the ADC acquisition module, high-voltage module and motor control drive module are respectively connected to the ARM central processing module; the ARM central processing module is connected to an external computer through the communication interface; The ARM central processing module controls the high-voltage module to apply voltage to the ionization chamber according to the command issued by the computer, controls the position of the ionization chamber by controlling the motor control drive module, and then controls the ionization chamber signal by controlling the ADC acquisition module and transmits it to the computer. The computer completes the integrated depth dose curve measurement based on the received ionization chamber signal, including: The ARM central processing module initializes the measuring device according to the initialization command issued by the computer; The ARM central processing module sends the voltage value applied by the high-voltage module and the position of the main ionization chamber controlled by the motor control drive module through the guide motor to the computer according to the status detection command issued by the computer, so as to determine whether the measuring device is in normal working state; In a state where no beam is applied, the ARM central processing module measures the background noise of the two ionization chambers respectively according to a data acquisition command issued by the computer, and uploads the data to the computer; wherein the measuring the background noise of the two ionization chambers respectively includes: measuring the current values ​​of the two ionization chambers respectively at a fixed frequency to obtain the background noise values ​​of the two ionization chambers respectively; Under the application of specified beam energy, the ARM central processing module sets the movement range of the main ionization chamber in the water tank and the movement step length of the guide motor according to the parameter setting command issued by the computer; The ARM central processing module drives the guide rail motor through the motor control drive module according to the measurement command issued by the computer, and drives the main ionization chamber to move to the specified position. The two ADC acquisition modules respectively collect corresponding ionization chamber signals and upload them to the computer. The computer combines the ionization chamber signals with the corresponding ionization chamber background noise to obtain the integrated depth dose curve measurement results at the specified position under the specified beam energy; according to the set movement step length of the guide rail motor, measurements are performed at different positions within the set movement range to obtain the integrated depth dose curve measurement results at the specified beam energy and the movement step length within the set movement range; By applying different beam energies and issuing parameter setting commands and measurement commands through the computer, the integrated depth dose curve measurement results of the moving step within the set moving range under different beam energies are finally obtained.

2. The integrated depth dose curve measurement device for proton therapy according to claim 1, characterized in that: There are two front-end amplifier modules and two ADC acquisition modules, which are connected one-to-one. There are two ionization chambers, one for the main ionization chamber and the other for the reference ionization chamber. Both ionization chambers are applied with voltage through the high-voltage module and are independently connected to a front-end amplifier module. The main ionization chamber is placed in a water tank, and the guide motor is driven by the motor control drive module to move the main ionization chamber. During the measurement process, the ARM central processing module transmits the ionization chamber signals collected by the two ADC acquisition modules to the computer, and the computer completes the integrated depth dose curve measurement based on the received ionization chamber signals.

3. The integrated depth dose curve measurement device for proton therapy according to claim 1, characterized in that: The initialization of the measuring device includes: moving the guide rail motor to the test origin, and applying high voltage to the two ionization chambers to make the ionization chambers work in the saturation zone.

4. The integrated depth dose curve measurement device for proton therapy according to claim 1, characterized in that: The computer combines the ionization chamber signal with the corresponding ionization chamber background noise to obtain the integrated depth dose curve measurement results at the specified beam energy and the specified position, including: The computer subtracts the ionization chamber signal of the same ionization chamber from the corresponding ionization chamber background noise to obtain two subtracted ionization chamber signals, and then performs a ratio to obtain an integrated depth dose curve measurement result at a specified beam energy and a specified position.

5. The integrated depth dose curve measurement device for proton therapy according to any one of claims 1 to 4, characterized in that: Also includes: Power supply module connected to the measuring device.

6. A method for measuring an integrated depth dose curve for proton therapy, characterized in that: Implementation based on the measuring device according to any one of claims 1 to 5, the steps include: Step 1: Connect the main ionization chamber, reference ionization chamber, and guide rail motor to the measuring equipment respectively, and turn on the power of the measuring equipment; Step 2: Send an initialization command via the computer, and the ARM central processing module initializes the measurement equipment, including: Step 3: The computer issues a status detection command, and the ARM central processing module sends the voltage value applied by the high-voltage module and the position of the main ionization chamber controlled by the motor control drive module through the guide motor to the computer to determine whether the measuring device is in normal working condition; Step 4: In the absence of beam current, the computer issues a data acquisition command, and the ARM central processing module and the ADC acquisition module respectively measure the background noise of the two ionization chambers and upload the data to the computer. Step 5: Under the specified beam energy, the computer sends parameter setting commands, and the ARM central processing module sets the movement range of the main ionization chamber in the water tank and the movement step size of the guide motor; Step 6: The computer issues a measurement command, and the ARM central processing module controls the motor control drive module to drive the guide motor to move the main ionization chamber to the specified position. The two ADC acquisition modules each collect the corresponding ionization chamber signal and upload it to the computer. The computer combines the ionization chamber signal with the corresponding ionization chamber background noise to obtain the integrated depth dose curve measurement result at the specified beam energy and the specified position. Step 7: Based on step 6, measurements are performed at different positions within the set moving range using the set moving step length of the guide motor to obtain an integrated depth dose curve measurement result for the moving step length within the set moving range at the specified beam energy; Step 8: Change the beam energy and repeat steps 6 and 7 to obtain the integrated depth dose curve measurement results of the moving step within the set moving range under different beam energies.

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