Radiotherapy quality control die body

Abstract

The utility model provides a multifunctional radiotherapy quality control motif, according to a specific embodiment, the multifunctional radiotherapy quality control motif comprises a light limiting cylinder and a dose motif, the dose motif is located below the light limiting cylinder, the dose motif comprises a shell, a surface dose measurement plug-in and a point dose measurement plug-in, and the shell is located below the light limiting cylinder. The surface dose measurement insert and the point dose measurement insert are configured to be insertable within the housing. The multifunctional radiotherapy quality control die body provided by the utility model can be used for verifying the accuracy of electron beam dose, and is helpful for improving the control accuracy of an electron beam radiotherapy robot.

Description

Technical Field

[0001] The utility model generally relates to the field of radiotherapy equipment, and particularly to a multifunctional radiotherapy quality control phantom for electron beam radiotherapy. Background Art

[0002] Radiotherapy is one of the important means of current tumor treatment and occupies an important position in the field of tumor treatment. High-energy electron beam is one of the commonly used radiation beams in external radiotherapy, and its usage frequency is second only to the X(γ) ray beam. Compared with the X(γ) ray beam, the high-energy electron beam has a limited range and can effectively avoid irradiating normal tissues behind the target area, and is commonly used for the treatment of superficial tumors.

[0003] With the advent of the era of precise radiotherapy, using robots for electron beam radiotherapy has become a research hotspot. The ray beam of the electron beam radiotherapy robot can move under the control of the motion platform, and it is necessary to evaluate whether the dosimetric characteristics of the ray beam meet the requirements after movement. According to the national standard requirements, it is necessary to complete the measurement of the off-axis dose curve and output of the ray beam at non-zero angles. However, there is currently no dose quality control phantom suitable for this research, which may make it difficult to ensure the safety and quality of radiotherapy. Summary of the Utility Model

[0004] In order to solve at least one of the above-mentioned defects in the prior art, the utility model patent proposes a multifunctional radiotherapy quality control phantom, which can be used to simulate the radiotherapy process of patients and verify the accuracy of the ray beam dose.

[0005] Specifically, the utility model provides a multifunctional radiotherapy quality control phantom, including: a collimator; and a dose phantom, which is located below the collimator. The dose phantom includes a housing, a surface dose measurement plug-in and a point dose measurement plug-in, and the surface dose measurement plug-in and the point dose measurement plug-in are configured to be insertable into the housing.

[0006] In some embodiments, the collimator has a top end and a bottom end, and the top end is provided with a card slot connected to the ray beam device, so that the collimator can move together with the ray beam device.

[0007] In some embodiments, the housing is a cylinder, a cube or a cuboid, and is configured to accommodate the surface dose measurement plug-in and the point dose measurement plug-in.

[0008] In some embodiments, the surface dose measurement plug-in has a groove, and the groove is configured to place a film for measuring the surface dose of the ray beam.

[0009] In some embodiments, the surface dose measurement plug-in has a multi-layer structure, and each layer structure has a different thickness.

[0010] In some embodiments, the multi-layer structure includes a film cassette bottom, a film cassette cover, and a film cassette backplane.

[0011] In some embodiments, the point dose measurement plug-in has a jack, and the circular hole is configured to place an ionization chamber for measuring the point dose of a radiation beam. Among them, the jack may have a circular cross-section.

[0012] In some embodiments, the point dose measurement plug-in has a plurality of jacks for placing ionization chambers at different heights, so as to realize point dose measurement at different depths.

[0013] In some embodiments, the point dose measurement plug-in has a cuboid shape, so that it can still be inserted into the housing after being rotated 180°.

[0014] In some embodiments, the radiotherapy quality control phantom further includes an insert block, which is configured to be inserted into the slot for the surface dose measurement plug-in in the housing when performing point dose measurement, or inserted into the slot for the point dose measurement plug-in in the housing when performing surface dose measurement.

[0015] Based on some embodiments, using the test phantom of the present utility model can verify the accuracy of the electron beam dose, which helps to improve the precision of the control of the electron beam radiotherapy robot, thereby ensuring the safety of external radiotherapy using the electron beam radiotherapy robot.

[0016] The above and other features and advantages of the present utility model will become apparent from the following description of exemplary embodiments in conjunction with the accompanying drawings. It should be understood that the exemplary embodiments may not necessarily achieve all these advantages. Therefore, the present utility model may be embodied or implemented in a manner that realizes or optimizes one or a group of advantages as taught herein, without necessarily realizing other advantages as taught or suggested herein. Description of the Drawings

[0017] The following discusses various aspects of at least one example with reference to the accompanying drawings, which are not intended to be drawn to scale. The inclusion of the drawings is to provide an illustration and further understanding of the various aspects and examples, and the drawings are incorporated into and constitute a part of this specification, but are not intended to be a definition of the limitations of the present application. In the drawings, each identical or almost identical component shown in each figure is represented by the same numeral. For clarity, not every component is labeled in each drawing. In the figures:

[0018] Figure 1 is a schematic structural diagram of a multi-functional radiotherapy quality control phantom according to an embodiment of the present utility model;

[0019] Figure 2 is a schematic diagram of the structure and installation of a surface dose measurement plug-in according to an embodiment of the present utility model;

[0020] Figure 3 The structure and installation schematic diagram of a point dose measurement plug-in according to an embodiment of the present utility model. Specific embodiments

[0021] In order to make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and the present invention is not limited to the exact forms of these exemplary embodiments.

[0022] Figure 1 The overall structure schematic diagram of a multifunctional radiotherapy quality control phantom according to an embodiment of the present utility model is shown. As Figure 1 shown, the multifunctional radiotherapy quality control phantom mainly includes two parts: an upper collimator and a lower dose phantom. Among them, the collimator is used to dock with a beam device that emits electron beams. In one embodiment, the beam device can be, for example, a part of a radiotherapy robot. The dose phantom is located below the collimator and is used to verify the dose of the beam passing through the collimator.

[0023] The collimator 100 can be a cylinder with a through hole of a specific shape (such as a round hole), and the barrel body has a certain wall thickness. Although the barrel body is shown as a cylinder in Figure 1 , it can be understood that the barrel body is not limited to the above cylindrical shape, but can be changed to a cone, a spherical frustum or other regular or irregular shapes according to actual needs.

[0024] In one embodiment, the collimator 100 has a top end and a bottom end. Among them, the top end can be connected to the beam device and can move together with the beam device. Referring to Figure 1 , an adapter card slot 104 for connecting to the beam device can be provided on the upper part of the collimator, which can ensure that the multifunctional quality control phantom will not loosen when moving together with the beam device. Obviously, the present application is not limited to the above connection method, but other various possible connection methods such as positioning pins can also be used. The bottom end of the collimator can be fixedly connected to the dose phantom to ensure that it will not loosen during movement. Similarly, the dose phantom can be connected to the collimator and fixed on the collimator by means of a snap structure, bonding, positioning pins, etc. The present application does not make specific limitations.

[0025] Referring to Figure 1, the dose phantom is located below the collimator 100, and the two are detachably connected. The dose phantom may specifically include a housing 101, a surface dose measurement plug-in and a point dose measurement plug-in. Among them, the surface dose measurement plug-in and the point dose measurement plug-in are configured to be insertable into the housing 101. For example, a point dose measurement plug-in slot 102 and a surface dose measurement plug-in slot 103 are provided in the housing 101. Among them, the point dose measurement plug-in can be inserted into the slot 102, and the surface dose measurement plug-in can be inserted into the slot 103. The exemplary specific structure of the plug-in will be specifically described below. Preferably, as Figure 1 shown, the slot 102 is located below the slot 103, but it can be understood that the present application is not limited thereto, and the two may also have other positional relationships. For example, the slot 102 is located above the slot 103.

[0026] In one embodiment, the dose phantom can be prepared from a soft tissue equivalent material and has relatively high hardness so as to be fixed below the collimator. For example, the phantom housing 101 can be specifically made of plexiglass or the like, which serves to connect the upper collimator and accommodate the point dose measurement plug-in and the surface dose measurement plug-in. In one embodiment, the phantom housing can have a cylindrical, cubic or cuboid shape. For example, it is a cylinder with a diameter of 120 mm and a height of 100 mm.

[0027] In one embodiment, the surface dose measurement plug-in may have a dose cassette (such as a film cassette) for placing a radiation detector such as a film. The plane dose in the direction perpendicular to the radiation beam can be measured through simulated radiation. The point dose measurement plug-in may have a dose cassette for placing a radiation detector such as an ionization chamber. The ionization chamber is connected to an electrometer to measure the point dose in the direction perpendicular to the radiation beam.

[0028] The structures and usage methods of the surface dose measurement plug-in and the point dose measurement plug-in will be described below.

[0029] Figure 2 FIG. shows a schematic structural diagram of a surface dose measurement plug-in according to an embodiment of the present invention. In one embodiment, the surface dose measurement plug-in may have a multi-layer structure, and each layer structure may be composed of a soft tissue equivalent material and have different thicknesses. In this way, different combinations can be used to achieve surface dose measurements at different depths.

[0030] As Figure 2As shown in FIGS. a-c, the surface dose measurement plug-in includes, from bottom to top, a film cassette bottom, a film cassette cover, and a film cassette matching plate. As shown in the figure, the film cassette bottom 200 and the film cassette cover 201 form the film cassette of the surface dose measurement plug-in. The film cassette can form a groove shape, for example, in which a film can be placed (e.g., at 202), and the film cassette cover 201 can cover the film. The top view cross-section of the film cassette matching plate 204 is the same as that of the film cassette bottom 200, and it has a certain thickness and is used in combination with the film cassette to achieve surface dose measurements at different depths. In one embodiment, the thickness of the upper surface of the dose phantom housing (i.e., the distance between the upper surface of the slot 103 and the upper surface of the housing) is 6 mm, the film cassette cover 201 has a thickness of 5 mm, and the film cassette matching plate 204 has a thickness of 10 mm. Thus, by combination, measurement depths of 11 mm (using only the film cassette cover 201), 16 mm (using only the film cassette matching plate 204), and 21 mm (using both the film cassette cover 201 and the film cassette matching plate 204) can be achieved, which respectively correspond to the measurement depths of the surface dose of electron beam radiotherapy with 6 MeV, 9 MeV, and 12 MeV beam energies.

[0031] When performing the measurement verification of the surface dose, the surface dose measurement plug-in is installed in the slot 103 with its center on the central axis of the beam. In some embodiments, the insert block 203 of the surface dose verification plug-in can also be provided, which can be used to fix the film cassette and fill the slot 102 of the point dose measurement plug-in. The insert block 203 can be made of a soft tissue equivalent material to ensure the uniformity of the quality control phantom.

[0032] Figure 3 FIG. shows a schematic structural diagram of the point dose measurement plug-in according to an embodiment of the present invention. In one embodiment, the point dose measurement plug-in can employ an ionization chamber adapter block 300, which can also be composed of a soft tissue equivalent material and has an overall shape adapted to the slot 102. Preferably, it can have an outer shape such as a cuboid, so that it can still be inserted into the slot 102 of the housing after being rotated 180°.

[0033] Figure 3 FIG. a shows a side view of the ionization chamber adapter block 300, which has an overall cuboid structure. In one embodiment, one or more lateral / vertical protrusions can be provided on its side. Among them, the lateral protrusions can be used to guide the ionization chamber adapter block 300 into the slot 102, and the vertical protrusions can increase the friction between the two, thereby improving the stability of the measurement plug-in.

[0034] Figure 3Figure b shows a front view of the ionization chamber adapter block 300, on which there may be jacks for placing an ionization chamber for measuring the point dose of the measurement point. The ionization chamber can be inserted into the jacks to measure the point dose of the beam. In some embodiments, a plurality of jacks may be provided at different heights of the ionization chamber adapter block 300, so as to realize the measurement of the point dose at different depths. As shown in the figure, the ionization chamber jacks 301 and 302 are asymmetrically arranged in the ionization chamber adapter block 300. Specifically, the jacks 301 and 302 are respectively at a first distance d1 and a second distance d2 from the upper surface and the lower surface of the ionization chamber adapter block, where d1 and d2 are not equal.

[0035] When the jack 301 is on the top and the jack 302 is on the bottom, that is Figure 3 as shown in b, inserting the ionization chamber into the jack 301 can realize the measurement of the point dose at the depth d1; when the ionization chamber adapter block 300 is rotated 180°, the jack 302 is on the top and the jack 301 is on the bottom, and inserting the ionization chamber into the jack 302 can realize the measurement of the point dose at the depth d2. In one embodiment, assuming that the thickness of the upper surface of the dose phantom housing is 6 mm, d1 and d2 are 5 mm and 15 mm respectively, and the two placement methods can respectively achieve measurement depths of 11 mm and 21 mm, corresponding to the measurement depths of the maximum dose point of the 6 MeV beam and the point dose at the 90% dose depth in electron beam radiotherapy.

[0036] When performing the measurement verification of the point dose, install the point dose measurement plug-in into the slot 102 so that the effective measurement points of the ionization chambers placed in the jacks 301 and 302 are located on the central axis of the beam. In some embodiments, one or more inserts 303 of the point dose verification plug-in (such as Figure 3 shown in c) can be provided, which can be used to fix the ionization chamber adapter block and fill the surface dose measurement plug-in slot 103. The insert 303 can be made of soft tissue equivalent material to ensure the uniformity of the quality control phantom.

[0037] Although Figure 3 the point dose measurement plug-in is described by taking two ionization chamber jacks as an example, the present invention is not limited thereto. In other embodiments, 3 or more ionization chamber jacks can be provided on the ionization chamber adapter block. Similarly, although Figure 3 the ionization chamber jacks 301 and 302 in are shown as circular hole cross-sections, it can be understood that the ionization chamber jacks 301 and 302 can also have other cross-sectional shapes such as square.

[0038] Using the multifunctional radiotherapy quality control phantom of the present utility model, it is possible to measure the surface dose of the plane perpendicular to the central axis of the radiation beam and the point dose at a certain depth on the central axis when the radiation beam is at different angles. Thus, the phantom of the present utility model can verify the dosimetric characteristics when the radiation beam is at different angles, ensuring the accuracy of radiotherapy. For example, the phantom of the present utility model can be applied to verify the metrological characteristics of an electron beam radiotherapy robot during movement, ensuring the safety of external radiotherapy using the electron beam radiotherapy robot.

[0039] The basic principles of the present application have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, benefits, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, benefits, effects, etc. are essential for each embodiment of the present application. In addition, the above-disclosed specific details are only for the purposes of illustration and facilitating understanding, rather than limitations, and the above details do not limit the present application to necessarily adopt the above specific details for implementation.

[0040] In this article, words such as "including", "comprising", "having", etc. are open-ended words, meaning "including but not limited to", and can be used interchangeably with each other. The word "or" and "and" used here refer to the word "and / or", and can be used interchangeably with each other, unless the context clearly indicates otherwise. The word "such as" used here refers to the phrase "such as but not limited to", and can be used interchangeably with each other.

[0041] The above is only the preferred arrangement mode of the present utility model and is not intended to limit the present utility model. Many combinations, modifications, and changes are obvious to those of ordinary skill in the art of this technology without departing from the scope and spirit of the embodiments described in the present utility model. Therefore, the protection scope of the present utility model should be defined by the scope of the claims.

Claims

1. A radiotherapy quality control phantom, characterized in that: include: Light limiting tube; as well as The dose phantom is located below the light-limiting cylinder. The dose phantom comprises a housing, a surface dose measurement plug-in and a point dose measurement plug-in. The surface dose measurement plug-in and the point dose measurement plug-in are configured to be inserted into the housing.

2. The radiotherapy quality control phantom according to claim 1, wherein: The light-limiting cylinder has a top end and a bottom end, and the top end is provided with a slot connected to the ray beam device, so that the light-limiting cylinder can move together with the ray beam device.

3. The radiotherapy quality control phantom according to claim 1, wherein: The housing is a cylinder, a cube or a cuboid, and is configured to accommodate the surface dose measurement plug-in and the point dose measurement plug-in.

4. The radiotherapy quality control phantom according to claim 1, wherein: The surface dose measurement plug-in has a groove configured to place a film for measuring the surface dose of a radiation beam.

5. The radiotherapy quality control phantom according to claim 1 or 4, wherein: The surface dose measurement insert has a multi-layer structure, and each layer has a different thickness.

6. The radiotherapy quality control phantom according to claim 5, wherein: The multi-layer structure comprises a film box bottom, a film box cover and a film box matching plate.

7. The radiotherapy quality control phantom according to claim 1, wherein: The point dose measurement plug-in has a socket configured to place an ionization chamber for measuring a point dose of a radiation beam.

8. The radiotherapy quality control phantom according to claim 1 or 7, wherein: The point dose measurement plug-in has a plurality of sockets for placing ionization chambers at different heights, thereby realizing point dose measurement at different depths.

9. The radiotherapy quality control phantom according to claim 8, wherein: The point dose measurement plug-in has a rectangular parallelepiped shape, so that it can still be inserted into the housing after being rotated 180°.

10. The radiotherapy quality control phantom according to claim 1, wherein: The radiotherapy quality control phantom also includes an insert block, which is configured to be inserted into a slot for the surface dose measurement insert block in the housing when performing point dose measurement, or to be inserted into a slot for the point dose measurement insert block in the housing when performing surface dose measurement.

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