Test equipment and test methods for verifying the dose and energy stability of radiotherapy equipment

Abstract

The present invention provides a test device and method for verifying the dose and energy stability of radiotherapy equipment. The test device comprises a connecting structure detachably connected to the radiotherapy equipment and a test structure connected to the connecting structure. The connecting structure has a connecting hole through which radiation emitted by the radiotherapy equipment enters the test structure, and the test structure measures the energy emitted by the radiotherapy equipment. This invention addresses the complex QA process associated with radiotherapy equipment in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of testing equipment, and in particular to a testing device and a testing method for calibrating the dose and energy stability of radiotherapy equipment. Background Art

[0002] The goal of radiotherapy is to deliver an adequate radiation dose to the target tumor while minimizing the dose to surrounding normal tissues and organs, thereby improving local tumor control and patient survival. The key to achieving this goal lies in rigorous quality control throughout the entire treatment process. Quality control of radiotherapy equipment and treatment plans is a key component of the overall radiotherapy quality assurance system. Verifying the stability of the energy and dose of radiation emitted by radiotherapy equipment is a crucial step in the equipment quality assurance process.

[0003] Taking conventional electron linear accelerators as an example, daily, monthly, and annual inspections often require testing of X-ray dose output stability and electron beam metering output stability. The X-ray and electron beam quality (i.e., energy) is also verified to ensure it is within a pre-set tolerance. Common testing methods include using water tanks or solid water phantoms. For example, when using a water tank to verify an electron beam radiation source, the specific testing process for dose and energy stability is as follows: The water tank is placed below the beam, and the water level is adjusted to ensure the SSD (Source-Surface Distance) is consistent with the normal treatment distance (typically 100 cm). The detector position is calibrated to ensure the zero point is at the center of the irradiation field above the water surface. The detector is moved to the depth corresponding to the maximum dose, and the device delivers a dose of D0 (or other value). The actual dose reading Dm is recorded. The deviation between Dm and D0 should be less than ±3%. The dose detector is moved to the 50% dose position and the depth corresponding to 50% dose, R50, is measured. The deviation between R50 and the factory value should not exceed ±3%. If a solid water phantom is used, the measurement process is similar and requires precise positioning of the solid water. The operation process is complex and tedious, and the test process requires relatively precise manual positioning.

[0004] That is to say, the radiotherapy equipment in the prior art has the problem of complex QA (Quality Assurance) process. Summary of the Invention

[0005] The main purpose of the present invention is to provide a test device and a test method for calibrating the dose and energy stability of radiotherapy equipment, so as to solve the problem of complex QA process of radiotherapy equipment in the prior art.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a test device for calibrating the dose and energy stability of radiotherapy equipment is provided, comprising: a connecting structure, which is detachably connected to the radiotherapy equipment; a test structure, which is connected to the connecting structure, and the connecting structure has a connecting hole. The rays emitted by the radiotherapy equipment are emitted into the test structure through the connecting hole, and the test structure measures the energy emitted by the radiotherapy equipment.

[0007] Furthermore, the test structure includes: a water mold, the water mold has multiple test holes, and the multiple test holes are arranged at intervals along the extension direction of the connecting structure; a dose probe, which is detachably arranged in the test hole to measure the dose at different depths.

[0008] Furthermore, a side surface of the water model close to the radiotherapy device is located at a preset SSD position of the radiotherapy device.

[0009] Furthermore, the water model includes: a body connected to the connection structure, and an outer peripheral surface of the body has a groove; a test body, the test body is detachably arranged in the groove, and the test body has a test hole.

[0010] Furthermore, there are multiple test bodies, and the multiple test bodies are replaceably arranged in the groove, and the test holes of the multiple test bodies are at different positions.

[0011] Furthermore, there are two test holes, and the test hole closer to the radiotherapy equipment is the maximum dose test hole. The distance between the maximum dose test hole and the surface of the water model close to the radiotherapy equipment is equal to the depth corresponding to the maximum dose in the percentage dose depth curve of the radiation emitted by the radiotherapy equipment in the water model; the test hole farther away from the radiotherapy equipment is the 50% dose test hole, and the distance between the 50% dose test hole and the surface of the water model close to the radiotherapy equipment is equal to the depth corresponding to the 50% dose in the percentage dose depth curve of the radiation emitted by the radiotherapy equipment in the water model.

[0012] Furthermore, the test structure also includes a dosimeter, which is electrically connected to a dose probe, and the dose probe transmits the detected dose to the dosimeter for display.

[0013] Further, the length of the connecting structure is adjustable; or the length of the connecting structure is not adjustable.

[0014] Furthermore, the density of the material of the test structure is greater than or equal to 0.9 g / cm 3 And less than or equal to 1.3g / cm 3 .

[0015] Furthermore, the test structure is detachably connected to the connection structure.

[0016] According to another aspect of the present invention, a test method for detecting the dose and energy stability of radiotherapy equipment is provided. The test method for detecting the dose and energy stability of radiotherapy equipment uses the above-mentioned test equipment for calibrating the dose and energy stability of radiotherapy equipment. The test method for detecting the dose and energy stability of radiotherapy equipment includes the following steps: Step S10: connecting the connecting structure of the test equipment to the head of the radiotherapy equipment; Step S20: selecting water models of different types of test equipment according to the energy required to be detected by the radiotherapy equipment; Step S30: placing the dose probe of the test equipment into the maximum dose test hole of the water model, and filling the water model with a solid water model of the same material as the water model. 50% dose test hole; step S40: controlling the irradiation dose D0 of the radiotherapy device; step S50: reading the dose D100 measured by the test structure of the test device, and recording the deviation between D100 and D0; step S60: placing the dose probe into the 50% dose test hole, and filling the maximum dose test hole with a solid water model of the same material as the water model; step S70: controlling the irradiation dose D0 of the radiotherapy device; step S80: reading the dose D50 measured by the test structure of the test device, and recording the 50% deviation between D50 and D0; repeating steps S30 to S80 to obtain the dose stability and energy stability of the output rays of the radiotherapy device at different energy levels.

[0017] Furthermore, the process of selecting different models of water phantoms according to the energy that the radiotherapy equipment needs to detect includes: selecting different models of water phantom test bodies according to the energy that the radiotherapy equipment needs to detect; embedding the test body into the body of the water phantom; and connecting the dose probe to the dose meter of the test equipment.

[0018] Applying the technical solution of the present invention, a test device for calibrating the dose and energy stability of radiotherapy equipment includes a connecting structure and a test structure, wherein the connecting structure is detachably connected to the radiotherapy equipment; the test structure is connected to the connecting structure, and the connecting structure has a connecting hole. The rays emitted by the radiotherapy equipment are emitted into the test structure through the connecting hole, and the test structure measures the energy emitted by the radiotherapy equipment.

[0019] By providing a connecting structure, the test device can be connected to the radiotherapy device, thus fixing the position between the two devices. Since the connecting structure is connected to the test structure, the position between the test structure and the radiotherapy device is fixed when the test device is connected to the radiotherapy device, eliminating the need to adjust the position of the test structure. This greatly simplifies the testing process and enables accurate measurement of the energy emitted by the radiotherapy device. Furthermore, manual movement of the test device is no longer required, significantly reducing labor costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 A schematic diagram showing the coordination relationship between the detection structure and radiotherapy equipment according to an optional embodiment of the present invention is shown.

[0022] The above drawings include the following reference numerals:

[0023] 10. Connection structure; 20. Test structure; 21. Water model; 211. Main body; 212. Test body; 22. Test hole. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0026] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity direction; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit the present invention.

[0027] In order to solve the problem of complex QA process of radiotherapy equipment in the prior art, the present invention provides a test device and a test method for calibrating the dose and energy stability of radiotherapy equipment.

[0028] like Figure 1 As shown, the test equipment for calibrating the dose and energy stability of radiotherapy equipment includes a connecting structure 10 and a test structure 20. The connecting structure 10 is detachably connected to the radiotherapy equipment; the test structure 20 is connected to the connecting structure 10, and the connecting structure 10 has a connecting hole. The rays emitted by the radiotherapy equipment are emitted into the test structure 20 through the connecting hole, and the test structure 20 measures the energy emitted by the radiotherapy equipment.

[0029] By providing connecting structure 10, the test device can be connected to the radiotherapy device, thus fixing the position between the test device and the radiotherapy device. Since connecting structure 10 is connected to test structure 20, when the test device is connected to the radiotherapy device, the position between test structure 20 and the radiotherapy device is fixed, eliminating the need to adjust the position of test structure 20. This greatly simplifies the testing process and enables accurate measurement of the energy emitted by the radiotherapy device. Furthermore, manual movement of the test device is no longer required, significantly reducing labor costs.

[0030] like Figure 1 As shown, the test structure 20 includes a water model 21 and a dose probe. The water model 21 has a plurality of test holes 22, and the plurality of test holes 22 are spaced apart along the extension direction of the connecting structure 10; the dose probe is detachably arranged in the test hole 22 to measure the dose at different depths. The energy emitted by the radiotherapy equipment is irradiated onto the water model 21, and the dose probe measures the energy irradiated onto the water model 21, and compares the dose value measured by the dose probe with the dose value emitted by the radiotherapy equipment to detect the dose stability and energy stability of the emitted rays of the radiotherapy equipment. The test hole 22 is set to accommodate the dose probe, so that the dose probe can measure the energy emitted by the radiotherapy equipment. By setting a plurality of test holes 22, different doses can be detected, making the test equipment more versatile.

[0031] It should be noted that the dose refers to the radiation dose, which refers to the amount of energy emitted by the radiotherapy equipment.

[0032] Specifically, the surface of the water phantom 21, which is closest to the radiotherapy device, is located at the device's preset SSD position. Since the normal treatment distance is the same as the SSD distance, this arrangement allows for monitoring the amount of energy emitted by the radiotherapy device at the treatment destination. By placing the water phantom 21 at the SSD position of the radiotherapy device, the amount of energy emitted by the device during treatment can be monitored, preventing over- or under-emission of radiation and ensuring the accuracy and efficiency of the treatment.

[0033] It should be noted that radiotherapy equipment may have a fixed or non-fixed SSD position. For non-fixed SSD radiotherapy equipment, a specific SSD distance for measurement is sufficient. The preset SSD position is the SSD position for fixed SSD radiotherapy equipment, and the specified SSD distance for non-fixed SSD radiotherapy equipment.

[0034] like Figure 1As shown, the water phantom 21 includes a main body 211 and a test body 212. The main body 211 is connected to the connecting structure 10 and has a groove on its outer surface. The test body 212 is detachably mounted within the groove and has a test hole 22. The main body 211 is connected to the connecting structure 10 to ensure a fixed distance between the main body 211 and the radiotherapy equipment, eliminating the need for adjustment of the main body 211 and enabling rapid testing of the radiotherapy equipment. The detachable arrangement of the test body 212 from the main body 211 facilitates replacement and maintenance of the test body 212 and also facilitates the assembly and disassembly of the dose probe, increasing the stability of the water phantom 21.

[0035] Optionally, multiple test bodies 212 are interchangeably positioned within the recess, with the test holes 22 of the test bodies 212 positioned differently. This configuration enables the testing device to test different energy doses emitted by the radiotherapy device, accurately measuring the stability of the radiotherapy device. The test bodies 212 are detachably connected to the main body 211 to facilitate replacement of the test bodies 212.

[0036] It should be noted that different rays can reach different positions at the same dose, so the doses emitted by different rays can be measured by using multiple test bodies 212 .

[0037] like Figure 1 As shown, there are two test holes 22. The one closest to the radiotherapy device is the maximum dose test hole. The distance between the maximum dose test hole and the surface of the water phantom 21 near the radiotherapy device is equal to the depth corresponding to the maximum dose of the radiation emitted by the radiotherapy device in the percent dose-depth curve of the water phantom 21. The one farther from the radiotherapy device is the 50% dose test hole. The distance between the 50% dose test hole and the surface of the water phantom 21 near the radiotherapy device is equal to the depth corresponding to the 50% dose of the radiation emitted by the radiotherapy device in the percent dose-depth curve of the water phantom 21. This arrangement allows measurement of the maximum dose and 50% dose emitted by the radiotherapy device. By comparing the data measured by the dose probe with the data emitted by the radiotherapy device, the stability of the radiation dose and energy of the radiation emitted by the radiotherapy device can be tested.

[0038] It should be noted that if the deviation between the data measured by the dose probe and the data emitted by the radiotherapy equipment is less than the specified value, it means that the stability of the energy emitted by the radiotherapy equipment meets the requirements.

[0039] Specifically, the test structure 20 also includes a dosimeter, which is electrically connected to a dose probe. The dose probe transmits the detected dose to the dosimeter for display. The dosimeter displays the dose measured by the dose probe, allowing the user to calculate the deviation between the dose measured by the dose probe and the dose delivered by the radiotherapy device, thereby detecting whether the energy stability of the radiotherapy device meets requirements.

[0040] Optionally, the length of the connecting structure 10 is adjustable. This arrangement allows the position of the test structure 20 to be adjusted, so that the test device can be adapted to different radiotherapy devices, thereby increasing the versatility of the test device.

[0041] Of course, the length of the connecting structure 10 can also be non-adjustable, so that one test device can only be used for one radiotherapy device, which is convenient for testing the test device. Since most test devices are custom-made, generally one test device can only be used for one radiotherapy device.

[0042] Specifically, the density of the material of the test structure 20 is greater than or equal to 0.9 g / cm 3 The density of the test structure 20 must be less than or equal to 1.3 g / cm³. It only needs to be that the density of the test structure material is close to that of water. For example, test structure 20 can be made of plexiglass, polyethylene, or RW3 solid water. Using a material with a density close to that of water effectively ensures that the energy emitted by the radiotherapy device can be diffused within test structure 20, facilitating testing of the dose stability and energy stability of the radiation emitted by the radiotherapy device.

[0043] Optionally, the test structure 20 is detachably connected to the connection structure 10. This arrangement facilitates replacement of the test structure 20, thereby ensuring that the test structure 20 can be stably and continuously tested.

[0044] The test method for detecting the dose and energy stability of radiotherapy equipment applies the above-mentioned test equipment for calibrating the dose and energy stability of radiotherapy equipment. The test method for detecting the dose and energy stability of radiotherapy equipment includes the following steps: Step S10: Connecting the connecting structure 10 of the test equipment to the head of the radiotherapy equipment; Step S20: Selecting different types of water models 21 according to the energy required to be detected by the radiotherapy equipment; Step S30: Placing the dose probe of the test equipment into the maximum dose test hole of the water model 21, and filling 50% of the dose test hole of the water model 21 with a solid water model of the same material as the water model 21; Step S40: Controlling the radiotherapy The device's irradiation dose D0 is measured; step S50: reading the dose D100 measured by the test structure 20 of the test device and recording the deviation between D100 and D0; step S60: placing the dose probe into the 50% dose test hole and filling the maximum dose test hole with a solid water phantom made of the same material as the water phantom 21; step S70: controlling the irradiation dose D0 of the radiotherapy device; step S80: reading the dose D50 measured by the test structure 20 of the test device and recording the 50% deviation between D50 and D0; repeating steps S30 to S80 to obtain the dose stability and energy stability of the radiotherapy device's output radiation at different energy levels. Using the above-mentioned test device for calibrating the dose and energy stability of radiotherapy devices can greatly simplify the operational process of the method for testing the content of the radiotherapy device's emitted dose, significantly reducing testing time. This testing method does not require adjustment of the test device; the test device can be directly installed on the radiotherapy device to accurately test the radiotherapy device.

[0045] Specifically, the process of selecting different models of water phantoms 21 according to the energy that the radiotherapy equipment needs to detect includes: selecting different models of test bodies 212 of the water phantom 21 according to the energy that the radiotherapy equipment needs to detect; embedding the test body 212 into the main body 211 of the water phantom 21; and connecting the dose probe to the dosimeter of the test equipment. Because different rays of the same energy emitted by the radiotherapy equipment can reach different locations, different rays can be detected by selecting different test bodies 212. The detachable connection between the test body 212 and the water phantom 21 eliminates the need to disassemble the entire test equipment to meet the needs of detecting different rays. The percentage dose depth curves of the same ray of different energies emitted by the radiotherapy equipment are also different, and the depths for the maximum dose and 50% dose are different. Therefore, by selecting different test bodies 212, different energies of the same ray can be detected.

[0046] Specifically, when inserting the test body 212 into the main body 211 of the water phantom 21, the test hole 22 corresponding to the energy to be tested is selected based on the energy level to be tested by the radiotherapy equipment. The dose probe of the testing equipment is placed in the corresponding test hole 22. The remaining test holes 22 on the test body 212 are filled with solid water phantoms made of the same material as the water phantom 21. The dose probe is then connected to the dosimeter of the testing equipment. This setup ensures the accuracy and stability of the dose probe test.

[0047] Obviously, the embodiments described above are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0048] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, tasks, devices, components and / or combinations thereof.

[0049] It should be noted that the terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0050] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A test device for verifying the dose and energy stability of radiotherapy equipment, characterized in that: include: A connecting structure (10), wherein the connecting structure (10) is detachably connected to the radiotherapy device; A test structure (20), the test structure (20) being connected to the connection structure (10), the connection structure (10) having a communication hole, the radiation emitted by the radiotherapy device being injected into the test structure (20) through the communication hole, and the test structure (20) measuring the energy emitted by the radiotherapy device; The test structure (20) comprises: A water mold (21), the water mold (21) having a plurality of test holes (22), the plurality of test holes (22) being arranged at intervals along an extension direction of the connection structure (10); a dose probe, the dose probe being detachably arranged in the test hole (22) to measure doses at different depths; The water model (21) includes: A body (211), the body (211) being connected to the connection structure (10) so that the distance between the position of the body (211) and the radiotherapy device remains fixed, and the body (211) does not need to be adjusted, so that the radiotherapy device can be quickly tested, and the outer peripheral surface of the body (211) has a groove; a test body (212), the test body (212) being detachably disposed in the groove, the test body (212) having the test hole (22); A side surface of the water model (21) close to the radiotherapy device is located at a preset SSD position of the radiotherapy device; There are a plurality of test bodies (212), and the plurality of test bodies (212) are replaceably arranged in the groove, and the positions of the test holes (22) of the plurality of test bodies (212) are different; The test structure (20) is detachably connected to the connection structure (10).

2. The test device for verifying the dose and energy stability of radiotherapy equipment according to claim 1, characterized in that: There are two test holes (22). The test hole (22) of the two test holes (22) that is close to the radiotherapy device is a maximum dose test hole, and the distance between the maximum dose test hole and the surface of one side of the water model (21) close to the radiotherapy device is equal to the depth corresponding to the maximum dose in the percentage dose depth curve of the radiation emitted by the radiotherapy device in the water model (21); The test hole (22) farther away from the radiotherapy device among the two test holes (22) is a 50% dose test hole, and the distance between the 50% dose test hole and the surface of one side of the water model (21) close to the radiotherapy device is equal to the depth corresponding to 50% dose in the percentage dose depth curve of the radiation emitted by the radiotherapy device in the water model (21).

3. The test device for verifying the dose and energy stability of radiotherapy equipment according to claim 1, characterized in that: The test structure (20) further includes a dose meter, which is electrically connected to the dose probe, and the dose probe transmits the detected dose to the dose meter for display.

4. The test device for verifying the dose and energy stability of radiotherapy equipment according to any one of claims 1 to 3, characterized in that: The length of the connecting structure (10) is adjustable; or The length of the connecting structure (10) is not adjustable.

5. The test device for verifying the dose and energy stability of radiotherapy equipment according to any one of claims 1 to 3, characterized in that: The density of the material of the test structure (20) is greater than or equal to 0.9 g / cm 3 And less than or equal to 1.3g / cm 3 .

6. A test method for detecting the dose and energy stability of radiotherapy equipment, characterized in that: The test method for detecting the stability of the dose and energy of radiotherapy equipment uses the test device for calibrating the stability of the dose and energy of radiotherapy equipment according to any one of claims 1 to 5, and the test method for detecting the stability of the dose and energy of radiotherapy equipment comprises the following steps: Step S10: connecting the connection structure (10) of the test device to the head of the radiotherapy device; Step S20: selecting water phantoms (21) of different models of the test equipment according to the energy required to be detected by the radiotherapy equipment; Step S30: placing the dose probe of the test device into the maximum dose test hole of the water model (21), and filling 50% of the dose test holes of the water model (21) with a solid water model made of the same material as the water model (21); Step S40: controlling the radiation dose D0 of the radiotherapy device; Step S50: reading the dose D100 measured by the test structure (20) of the test device, and recording the deviation between D100 and D0; Step S60: placing the dose probe into the 50% dose test hole, and filling the maximum dose test hole with a solid water mold made of the same material as the water mold (21); Step S70: controlling the radiation dose D0 of the radiotherapy equipment; Step S80: reading the dose D50 measured by the test structure (20) of the test device, and recording a 50% deviation between D50 and D0; Repeat steps S30 to S80 to obtain the dose stability and energy stability of the radiation outputted by the radiotherapy device at different energy levels.

7. The test method for detecting the dose and energy stability of radiotherapy equipment according to claim 6, characterized in that: The process of selecting different types of water phantoms (21) according to the energy required to be detected by the radiotherapy equipment includes: Selecting different models of test bodies (212) of the water model (21) according to the energy required to be detected by the radiotherapy equipment; embedding the test body (212) into the body (211) of the water model (21); Connect the dose probe to the dosimeter of the test equipment.

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