Dose detection method based on motif structure and motif structure

Abstract

The embodiment of the invention relates to a dose detection method based on a die body structure and the die body structure. The die body structure comprises a base, a first module, a second module, a plurality of insertion rods and a top cover, the base comprises a first module accommodating area, a second module accommodating area and a plurality of slots; the first module accommodating area is positioned at the upper part of the base; the second module accommodating area is positioned at the lower part of the base; the plurality of slots are arranged in parallel along the axial direction of the base; the first slot, the second slot and the fourth slot are communicated with the first module accommodating area, the first slot and the second slot are positioned on one side of the second module accommodating area, the third slot is respectively communicated with the first module accommodating area and the second module accommodating area, and the fourth slot is positioned on the other side of the second module accommodating area; the fifth slot and the sixth slot are symmetrically arranged on two sides of the second slot; the first module is accommodated in the first module accommodating area; the second module is accommodated in the second module accommodating area; the plurality of insertion rods are inserted into the plurality of insertion grooves according to preset requirements; and the top cover is buckled on the base.

Description

Technical Field

[0001] The present invention relates to the technical field of dose detection, and in particular to a dose detection method based on a phantom structure and a phantom structure. Background Art

[0002] Photon radiotherapy is one of the mainstream treatments for head and neck malignant tumors. Due to the large number of organs involved in the head and neck, it requires high conformality of tumor dose distribution, fast drop in dose outside the tumor, and low dose to organs at risk. Due to its highly conformal dosimetric characteristics, even a small deviation in the irradiation dose during treatment may lead to serious consequences. Currently, radiotherapy centers usually only carry out routine physical quality assurance (QA) and radiotherapy QA around each independent link in the radiotherapy chain. Such traditional QA tests for specific links or systems cannot essentially guarantee the accuracy of the patient's clinical irradiation dose after the entire treatment process.

[0003] In response to this problem, some institutions have adopted an "end to end" (E2E) QA test for radiotherapy, which is used to evaluate whether all components in the radiotherapy process work as expected, so that the planned radiation dose is accurately delivered to the predetermined spatial location. However, in terms of the test method, the remote audit method is still used, that is, the testing agency mails the test phantom together with the screened thermoluminescent dosimeter (TLD) and radiochromic film to the radiotherapy center. The radiotherapy center will send the phantom back after conducting the end-to-end QA test. The testing agency reads the TLD and radiochromic film dose information and performs data analysis. The disadvantages are: First, the remote end-to-end audit cycle is usually time-consuming, and the result analysis is lagging. Due to the long and complex radiotherapy chain of modern radiotherapy technology, when there are serious deviations in the QA test results, error analysis will face greater challenges. Second, TLD has large statistical fluctuations and is easily affected by environmental factors. Improper condition control will have an adverse effect on the measurement results. Third, the non-equivalence of the phantom material needs to be optimized. Summary of the invention

[0004] The purpose of the present invention is to provide a dose detection method based on a phantom structure and a phantom structure in view of the defects in the prior art.

[0005] To achieve the above-mentioned object, in a first aspect, the present invention provides a mold structure, the mold structure comprising: a base, a first module, a second module, a plurality of plugs and a top cover;

[0006] The base includes a first module accommodating area, a second module accommodating area and a plurality of slots;

[0007] The first module accommodating area is located at the upper part of the base;

[0008] The second module accommodating area is located at the lower part of the base;

[0009] The plurality of slots are arranged in parallel along the axial direction of the base, including a first slot, a second slot, a third slot, a fourth slot, a fifth slot and a sixth slot; the first slot, the second slot and the fourth slot are connected to the first module accommodating area, the first slot and the second slot are located on one side of the second module accommodating area, the third slot is connected to the first module accommodating area and the second module accommodating area respectively, and the fourth slot is located on the other side of the second module accommodating area; the fifth slot and the sixth slot are symmetrically arranged on both sides of the second slot,

[0010] And the connecting line is perpendicular to the connecting line of the first slot, the second slot, the third slot and the fourth slot;

[0011] The first module is accommodated in the first module accommodating area;

[0012] The second module is accommodated in the second module accommodation area;

[0013] The plurality of plugs are inserted into the plurality of slots according to preset requirements;

[0014] The top cover is buckled on the base.

[0015] Preferably, the base is a cylinder; the top cover is an arc shape; the bottom radius of the base is equal to the bottom radius of the top cover.

[0016] Preferably, the base is detachably connected to the top cover.

[0017] Preferably, the mold structure further includes a mold bracket; the base is cooperatively connected to the mold bracket.

[0018] Further preferably, the mold bracket is made of ABS plastic.

[0019] Preferably, the first module is implemented using brain tissue equivalent materials; the brain tissue equivalent materials include: 37.83% epoxy system, 34.57% polyethylene, 19.56% methyl methacrylate, 3.00% calcium oxide, 2.01% urea, 1.05% sodium dihydrogen phosphate, 0.67% dipotassium hydrogen phosphate, 0.20% sulfur, 0.01% red phosphorus and 1.10% phenolic microspheres.

[0020] Preferably, the second module is implemented using a bone equivalent material; the bone equivalent material includes: 48.00% epoxy system, 45.82% hydroxyapatite, 4.70% urea, 0.99% magnesium sulfate, 0.31% sodium sulfate and 0.18% calcium oxide.

[0021] Preferably, the plurality of plugs are made of polystyrene material.

[0022] Preferably, the base and the top cover are made of polystyrene material.

[0023] In a second aspect, the present invention provides a dose detection method based on any one of the phantom structures described in the first aspect, the dose detection method comprising:

[0024] positioning an ionization chamber at a point of interest within a phantom structure, and placing the phantom structure and ionization chamber in a phantom holder;

[0025] Using a three-dimensional laser light and marking points on the surface of the phantom structure to perform positioning, the phantom structure is subjected to CT scanning to obtain a scanned image;

[0026] Importing the scanned image into a treatment planning system, designing an irradiation plan according to the dose limit, and calculating dose calculation values ​​of points of interest in the treatment planning system;

[0027] Positioning the phantom structure and the ionization chamber on a medical electron linear accelerator treatment bed, irradiating the phantom structure according to the detection step, and obtaining an ionization chamber dose measurement value;

[0028] The detection result is obtained according to the dose calculation value of the point of interest and the dose measurement value of the ionization chamber in the treatment planning system.

[0029] A phantom structure provided by an embodiment of the present invention simulates the main structure of the head and neck by using a base and a top cover, and sets a first module accommodating area, a second module accommodating area and a slot on the base, and the second module is accommodated in the second module accommodating area. When dose detection is required, the first module can be selected and placed in the first module accommodating area, the plug rod can be placed in the corresponding slot, and the ionization chamber can be placed in the slot of the dose detection part, so that dose detection can be realized, and real-time measurement and evaluation can be performed, effectively shortening the detection cycle, and the detection results are more timely. Multiple choices for the first module can meet the needs of multiple tests, and the material selection of each module is closer to the characteristics of the brain, which helps to improve the accuracy of the detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A longitudinal cross-sectional view of a phantom structure provided by an embodiment of the present invention;

[0031] Figure 2A three-dimensional diagram of a phantom structure provided by an embodiment of the present invention;

[0032] Figure 3 A bottom view of a phantom structure provided by an embodiment of the present invention;

[0033] Figure 4 One of the cross-sectional views of a base provided by an embodiment of the present invention;

[0034] Figure 5 A second cross-sectional view of a base provided in an embodiment of the present invention;

[0035] Figure 6 A third cross-sectional view of a base provided in an embodiment of the present invention;

[0036] Figure 7-a One of the structural schematic diagrams of the first module provided in an embodiment of the present invention;

[0037] Figure 7-b A second structural diagram of the first module provided in an embodiment of the present invention;

[0038] Figure 7-c A third structural diagram of the first module provided in an embodiment of the present invention;

[0039] Figure 7-d A fourth structural diagram of the first module provided in an embodiment of the present invention;

[0040] Figure 7-e A fifth structural diagram of the first module provided in an embodiment of the present invention;

[0041] Figure 7-f A sixth structural diagram of the first module provided in an embodiment of the present invention;

[0042] Figure 7-g A seventh structural diagram of the first module provided in an embodiment of the present invention;

[0043] Figure 8 A comparison curve of the calculated attenuation coefficient of the brain equivalent material provided in an embodiment of the present invention and the recommended value in I CRU Report No. 44;

[0044] Fig. 9 A comparison curve of the calculated attenuation coefficient of the bone equivalent material provided in the embodiment of the present invention and the recommended value in I CRU Report No. 46;

[0045] Fig.10 A flow chart of a dose detection method based on a phantom structure provided in an embodiment of the present invention;

[0046] Fig.11 One of the ionization chamber positioning diagrams of the dose detection method based on the phantom structure provided in an embodiment of the present invention;

[0047] Fig.12 The second ionization chamber positioning diagram of the dose detection method based on the phantom structure provided in the embodiment of the present invention;

[0048] Fig.13 The third ionization chamber positioning diagram of the dose detection method based on the phantom structure provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments.

[0051] Figure 1 A longitudinal cross-sectional view of a phantom structure provided by an embodiment of the present invention, Figure 2 A three-dimensional diagram of the phantom structure provided by an embodiment of the present invention is shown below in conjunction with Figure 1 and Figure 2 , the technical solution of the present invention is described with specific embodiments.

[0052] A mold structure according to an embodiment of the present invention may specifically include: a base 1, a first module (such as Figure 7-a-7-g As shown in ), a second module 3, a plurality of plungers 4 and a top cover 5.

[0053] The base 1 may include a first module accommodating area 10, a second module accommodating area 11 and a plurality of slots. By way of example and not limitation, the base 1 may specifically be a cylinder. The first module accommodating area 10 is located at the upper portion of the base 1. The first module accommodating area 10 is simulated as a brain accommodating area. The second module accommodating area 11 is located at the lower portion of the base 1. The second module accommodating area 11 is simulated as a spinal accommodating area. The base 1 may be made of a polystyrene material having photon radiation characteristics equivalent to those of human muscle tissue, and is mainly used to simulate the main structure of the neck.

[0054] The front surface of the base 1 is also provided with a marking point 100. In this application, marking points (lead points) 100 are respectively provided at 3, 6, 9 and 12 o'clock directions, and a marking point 100 is provided on the central surface of the top cover 5. The marking point 100 can be a cross mark or a protrusion, which is not specifically limited in this application, as long as it meets the positioning and placement requirements for dosage detection.

[0055] Combination Figure 2 and 3As shown, a plurality of slots are arranged in parallel along the axial direction of the base 1 , and may specifically include a first slot 121 , a second slot 122 , a third slot 123 , a fourth slot 124 , a fifth slot 125 and a sixth slot 126 .

[0056] Recombination Figures 4 to 6 As shown, the first slot 121, the second slot 122 and the fourth slot 124 are connected to the first module accommodating area 11. The first slot 121 and the second slot 122 are located on one side of the second module accommodating area 11. The third slot 123 is connected to the first module accommodating area 10 and the second module accommodating area 11 respectively, and the fourth slot 124 is located on the other side of the second module accommodating area 11. The fifth slot 125 and the sixth slot 126 are symmetrically arranged on both sides of the second slot 122, and the connecting line is perpendicular to the connecting line of the first slot 121, the second slot 122, the third slot 123 and the fourth slot 124. It should be noted that the fifth slot 125 and the sixth slot 126 are not connected to the first module accommodating area 10.

[0057] The first module is accommodated in the first module accommodation area 10. The first module is detachably connected to the base 1. Figures 7-a to 7-g As shown in , the first module may specifically include seven submodules, namely, a first module 21, a first module 22, a first module 3, a first module 4, a first module 5, a first module 6, and a first module 7. When testing, four modules are selected and used in combination according to actual needs. The four modules may be completely different ( Fig.11 ), or they can be different ( Fig.12 ). The actual demand refers to the demand for disease detection, that is, different parts of the body need to be tested for doses.

[0058] The first module can be understood as a simulated brain module, which can be implemented by using brain tissue equivalent materials whose photon radiation characteristics are equivalent to those of human brain tissue. In the present application, the brain tissue equivalent materials include: 37.83% epoxy system, 34.57% polyethylene, 19.56% methyl methacrylate, 3.00% calcium oxide, 2.01% urea, 1.05% sodium dihydrogen phosphate, 0.67% dipotassium hydrogen phosphate, 0.20% sulfur, 0.01% red phosphorus and 1.10% phenolic microspheres.

[0059] Among them, the configuration of the epoxy system is as follows: first, bisphenol A epoxy resin, amine curing agent, and monoepoxy active diluent are used to form a mixture system to introduce the four main elements of H, C, N, and O in bones and brains; secondly, specific inorganic compounds and organic compound powders are added to the mixture system to introduce trace elements such as Na, P, S, Cl, K, Ca, Mg in bones and brains, and a small amount of H, C, N, and O elements; then, phenolic microspheres are used to adjust the mass density of the mixture when necessary; finally, the above materials are fully mixed, exhausted, cured, and processed into a shape to obtain an epoxy system.

[0060] Table 1 shows the elemental composition of brain equivalent materials.

[0061]

[0062] Table 1

[0063] The average density of the brain equivalent material of this application is 1.04 g / cm 3 ,like Figure 8 The value of brain tissue density recommended by the International Commission on Radiological Units I CRU 44 is 1.04 g / cm 3 ) is 0.00%. In the photon energy range of 50keV-10MeV for radiotherapy, the relative deviation between the calculated value of the linear attenuation coefficient of brain equivalent material and the recommended value of the linear attenuation coefficient of human brain tissue in I CRU Report No. 44 is better than ±5%.

[0064] The second module is accommodated in the second module accommodating area. The second module can be integrally connected to the base or detachably connected, and in the present application, it is integrally connected. The second module is implemented using a bone equivalent material having photon radiation characteristics equivalent to human bone tissue. In the present application, the bone equivalent material includes: 48.00% epoxy system, 45.82% hydroxyapatite, 4.70% urea, 0.99% magnesium sulfate, 0.31% sodium sulfate and 0.18% calcium oxide.

[0065] Among them, the configuration of the epoxy system is the same as that of the first module.

[0066] Table 2 shows the elemental composition of bone equivalent materials.

[0067]

[0068] Table 2

[0069] The average density of the bone equivalent material of this application is 1.58 g / cm 3 ,like Fig. 9 The value of brain tissue density recommended by the International Commission on Radiological Units I CRU 44 (1.61 g / cm3 ) is -1.86%. In the photon energy range of 50keV-10MeV for radiotherapy, the relative deviation between the calculated value of the linear attenuation coefficient of the bone equivalent material and the recommended value of the linear attenuation coefficient of the human skull in the I CRU Report No. 46 is better than ±5%.

[0070] The plurality of plug rods 4 are inserted into the plurality of slots according to preset requirements. The plurality of plug rods 4 are made of polystyrene material.

[0071] The top cover 5 can be specifically in the shape of an arc. The bottom radius of the top cover 5 is equal to the bottom radius of the base. By way of example and not limitation, the bottom radius of the top cover 5 can be 8 cm. The top cover 5 is snapped onto the base 1 and can be detachably connected to the base by means of a threaded connection. In the present application, the top cover 5 is connected to the base 1 by three screws 200. The top cover 5 can be made of a polystyrene material having photon radiation characteristics equivalent to those of human muscle tissue to simulate the main structure of the head.

[0072] In an optional solution, the mold structure further includes a mold bracket 6. The mold bracket 6 is a concave structure, and its concave portion is an arc shape. The mold bracket 6 is made of ABS plastic. The base 1 is connected with the mold bracket 6 in a cooperative manner.

[0073] In a preferred embodiment, in order to simulate the real skull and spinal column structure as much as possible, the model structure also includes a filling piece 7, which is located on the inner side of the top cover 5 and the outer side of the first module accommodating area 10. Specifically, the filling piece 7 can be implemented by a bone equivalent material having photon radiation characteristics equivalent to those of human bone tissue, that is, the same as the material of the second module 3.

[0074] The above introduces the composition of the model structure and the connection relationship between the various components. The following briefly introduces the use principle of the model structure.

[0075] Firstly, four first modules are selected according to actual needs, and the first modules are placed in the first module accommodating area 10 .

[0076] Secondly, according to actual needs, the ionization chamber is positioned, the ionization chamber is placed in the corresponding slot, and then the plug is placed in the slot. It should be noted that there are two situations for positioning the ionization chamber: the first is that the ionization chamber is directly inserted into the slot, and there is no need to place the plug at the position of the ionization chamber, that is, the depth of the slot is directly the depth required for positioning (such as Fig.11 The second method is to first place a rod of appropriate length in the slot where the ionization chamber needs to be placed, and then insert the rod into the ionization chamber to meet the required positioning depth of the ionization chamber (as shown in the figure). Fig.13 shown).

[0077] Then, the phantom structure is placed in the phantom bracket 6 .

[0078] Finally, the phantom is CT scanned and irradiated to detect the dose of the corresponding parts. Real-time measurement and evaluation can be performed, effectively shortening the detection cycle and making the detection results more timely.

[0079] A phantom structure provided by an embodiment of the present invention simulates the main structure of the head and neck by using a base and a top cover, and sets a first module accommodating area, a second module accommodating area and a slot on the base, and the second module is accommodated in the second module accommodating area. When dose detection is required, the first module can be selected and placed in the first module accommodating area, the plug rod can be placed in the corresponding slot, and the ionization chamber can be placed in the slot of the dose detection part, so that dose detection can be realized, and real-time measurement and evaluation can be performed, effectively shortening the detection cycle, and the detection results are more timely. Multiple choices for the first module can meet the needs of multiple tests, and the material selection of each module is closer to the characteristics of the brain, which helps to improve the accuracy of the detection.

[0080] The embodiment of the present invention further provides a dose detection method based on the above-mentioned phantom structure. It should be noted that the composition and material of the phantom structure in this method are the same as those in the above-mentioned embodiment and will not be described in detail herein.

[0081] This method mainly includes Fig.10 The steps shown in:

[0082] Step 110, positioning the ionization chamber at a point of interest inside the phantom structure, and placing the phantom structure and the ionization chamber in a phantom bracket;

[0083] Specifically, the ionization chamber can be positioned according to the target disease. The points of interest are related to the location of the target disease and the organs at risk, and can include the nasopharynx, pituitary gland, anterior lower brain, central brain, posterior upper brain, cerebellum, spine, left and right parotid glands and brain stem. When the phantom structure is placed in the phantom bracket, the phantom structure is in a supine position. Fig.11 As shown, the point of interest is equivalent to the front and lower part of the brain, that is, the ionization chamber is positioned in the first slot, and the plug is located in the second slot, the third slot, the fourth slot, the fifth slot and the sixth slot. Fig.12 As shown, the point of interest corresponds to the left / right parotid gland, that is, the ionization chamber is positioned in the fifth or sixth slot, and the rod is located in the first slot, the second slot, the third slot, the fourth slot and the sixth or fifth slot.

[0084] The ionization chamber of the present application can be a typical ionization chamber used in head dose detection, and the present application does not make any specific limitation.

[0085] Step 120, using the three-dimensional laser light and the marking points on the surface of the phantom structure to perform CT scanning on the phantom structure to obtain a scanned image;

[0086] Specifically, in the present application, marking points (lead points) are respectively set at the 3, 6, 9 and 12 o'clock directions on the front end surface of the base, and a marking point is set on the center surface of the top cover.

[0087] Step 130, importing the scanned image into the treatment planning system, designing an irradiation plan according to the dose limit, and calculating the dose calculation value of the point of interest in the treatment planning system;

[0088] Specifically, the Treatment Planning System (TPS) is a professional software system used in radiotherapy to calculate, optimize and evaluate the radiation dose distribution to ensure accurate irradiation of the tumor and minimize damage to healthy tissues. The target area and organs at risk can be delineated in the treatment planning system. The dose calculation value of the point of interest in the treatment planning system is expressed as D TPS express.

[0089] Step 140, positioning the phantom structure and the ionization chamber on a medical electron linear accelerator treatment bed, irradiating the phantom structure according to the detection step, and obtaining an ionization chamber dose measurement value;

[0090] Specifically, the irradiation time depends on the actual situation. Generally, the irradiation time is 10 minutes to 30 minutes. The ionization chamber dose measurement value is expressed as D meas The calculation formula is as follows:

[0091] D meas =M×N D,W ×k T,P

[0092] Where M represents the ionization chamber reading, k T,P Indicates the temperature / pressure correction factor, N D,W Represents the absolute dose calibration factor.

[0093] Step 150, obtaining a detection result according to the dose calculation value of the point of interest in the treatment planning system and the dose measurement value of the ionization chamber.

[0094] Specifically, the deviation δ is obtained according to the dose calculation value of the point of interest in the treatment plan system and the dose measurement value of the ionization chamber, and then the deviation is compared with the detection evaluation range to obtain the detection result. When the deviation falls within the detection evaluation range, it is considered that the detection is passed, otherwise, the detection is not passed, and after analysis, steps 110-150 are re-executed. By way of example and not limitation, the detection evaluation range is ±3%.

[0095] The calculation formula of the deviation δ is as follows:

[0096] δ=(D meas -D TPS ) / D TPS×100%

[0097] The detection method based on the phantom structure provided in the embodiment of the present invention can realize real-time measurement and evaluation of the dose data at the detection site by using the phantom structure and a small-volume ionization chamber. Compared with the current remote end-to-end dose detection mode, the detection cycle can be effectively shortened, the detection structure is more time-effective, and through the selection of the first module in the phantom structure, the radiation dose detection needs of different types of diseases can be met, and the scope of use is wider. The materials in the phantom structure are brain tissue equivalent materials and bone equivalent materials, so that the detection results are more valuable for reference.

[0098] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A phantom structure, characterized in that: The mold structure includes: a base, a first module, a second module, a plurality of plugs and a top cover; The base includes a first module accommodating area, a second module accommodating area and a plurality of slots; The first module accommodating area is located at the upper part of the base; The second module accommodating area is located at the lower part of the base; The plurality of slots are arranged in parallel along the axial direction of the base, and include a first slot, a second slot, a third slot, a fourth slot, a fifth slot and a sixth slot; the first slot, the second slot and the fourth slot are connected to the first module accommodating area, the first slot and the second slot are located on one side of the second module accommodating area, the third slot is connected to the first module accommodating area and the second module accommodating area respectively, and the fourth slot is located on the other side of the second module accommodating area; the fifth slot and the sixth slot are symmetrically arranged on both sides of the second slot, and the connecting line is perpendicular to the connecting line of the first slot, the second slot, the third slot and the fourth slot; The first module is accommodated in the first module accommodating area; The second module is accommodated in the second module accommodation area; The plurality of plugs are inserted into the plurality of slots according to preset requirements; The top cover is buckled on the base.

2. The phantom structure according to claim 1, characterized in that: The base is a cylinder; the top cover is an arc shape; the bottom radius of the base is equal to the bottom radius of the top cover.

3. The phantom structure according to claim 1, characterized in that: The base is detachably connected to the top cover.

4. The phantom structure according to claim 1, characterized in that: The mold structure also includes a mold bracket; the base is cooperatively connected with the mold bracket.

5. The phantom structure according to claim 4, characterized in that: The mold body bracket is made of ABS plastic.

6. The phantom structure according to claim 1, characterized in that: The first module is implemented using brain tissue equivalent materials; the brain tissue equivalent materials include: 37.83% epoxy system, 34.57% polyethylene, 19.56% methyl methacrylate, 3.00% calcium oxide, 2.01% urea, 1.05% sodium dihydrogen phosphate, 0.67% dipotassium hydrogen phosphate, 0.20% sulfur, 0.01% red phosphorus and 1.10% phenolic microspheres.

7. The phantom structure according to claim 1, characterized in that: The second module is implemented by bone equivalent material; the bone equivalent material includes: 48.00% epoxy system, 45.82% hydroxyapatite, 4.70% urea, 0.99% magnesium sulfate, 0.31% sodium sulfate and 0.18% calcium oxide.

8. The phantom structure according to claim 1, characterized in that: The plurality of plugs are made of polystyrene material.

9. The phantom structure according to claim 1, characterized in that: The base and the top cover are made of polystyrene material.

10. A dose detection method based on the phantom structure according to any one of claims 1 to 9, characterized in that: The dosage detection method comprises: positioning an ionization chamber at a point of interest within a phantom structure, and placing the phantom structure and ionization chamber in a phantom holder; Using a three-dimensional laser light and marking points on the surface of the phantom structure to perform positioning, the phantom structure is subjected to CT scanning to obtain a scanned image; Importing the scanned image into a treatment planning system, designing an irradiation plan according to the dose limit, and calculating dose calculation values ​​of points of interest in the treatment planning system; Positioning the phantom structure and the ionization chamber on a medical electron linear accelerator treatment bed, irradiating the phantom structure according to the detection step, and obtaining an ionization chamber dose measurement value; The detection result is obtained according to the dose calculation value of the point of interest and the dose measurement value of the ionization chamber in the treatment planning system.

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