Full spherical surface detector array-motif device

Abstract

The utility model relates to a full-sphere detector array-motif device, which belongs to the technical field of radiotherapy dose verification equipment and comprises a first sphere, a second sphere and a detector array. The first ball body is a hollow ball body; the second ball body is a solid ball body; the detector array is respectively connected with the first sphere and the second sphere; the detector array comprises a plurality of groups of detector units; the plurality of groups of detector units are sequentially arranged in rows on the outer surface of the second sphere from top to bottom; the full-spherical-surface detector array-motif device has the capability of full-angle dose measurement, is suitable for multi-angle, multi-depth and non-coplanar test items, is especially suitable for small-radiation-field and high-precision test items, obtains multiple x-ray signal data through the full-spherical-surface detector array, performs fitting calculation of the dose through the multiple x-ray signal data, and is high in accuracy and high in accuracy. Influence errors caused by the fitting difference value dose are reduced, and additional errors are prevented from being introduced in the testing process.

Description

Technical Field

[0001] The utility model relates to the technical field of radiotherapy dose verification equipment, in particular to a full spherical detector array-phantom device. Background Art

[0002] Stereotactic radiotherapy is an advanced tumor treatment method that uses a precise three-dimensional navigation system and radiation therapy equipment to accurately deliver high-energy rays to the tumor tissue in the patient's body. Through precise calculation and positioning, this technology can maximize the accuracy of radiotherapy while reducing damage to normal tissues. In order to fully utilize the technical advantages of stereotactic radiotherapy, achieve concentrated high-dose irradiation of the tumor target area, and ensure that the dose at the edge of the target area drops rapidly to reduce damage to surrounding critical organs, non-coplanar irradiation technology with multiple angles of incidence is used during the treatment process. This technology can effectively irradiate radiation from different angles accurately to the tumor target area, thereby achieving the purpose of treatment.

[0003] At present, clinical units mainly use film, two-dimensional matrix, three-dimensional dose verification equipment testing and comparative test project methods to carry out quality control testing of radiotherapy-related equipment and treatment plan verification. Existing two-dimensional verification equipment can usually only measure the dose of a single layer. However, for multi-angle, multi-depth, and non-coplanar test items, the measurement difficulty increases, and additional errors may be introduced, which will have an adverse effect on the test results. Existing three-dimensional verification equipment has the ability to measure doses from multiple angles. However, for small radiation fields and high-precision test items, these devices often cannot meet the needs.

[0004] The Chinese patent application with publication number CN 115804917 A verifies the output plan of non-isocentric and non-coplanar radiotherapy equipment by closely combining a multi-layer detector array with a multi-layer phantom. However, the combination of a multi-layer detector and a multi-layer phantom will increase the path size of the beam passing through the device, and for multi-angle, non-coplanar, and small radiation field test items, it will introduce positioning errors and have an adverse effect on the test results. In addition, since the invention fits the dose distribution on a limited number of detectors, the results cannot fully guarantee authenticity and accuracy, and additional equipment needs to be introduced to verify the data results.

[0005] The Chinese patent with announcement number CN106501839B is equipped with a multi-layer detector to improve the verification accuracy of the spatial distribution of dose. Although the verification accuracy of the spatial distribution of dose can be improved, the device uses a multi-layer detector to increase the path size of the beam passing through the device, which is not suitable for quality control testing of stereoscopic radiotherapy with a small radiation field.

[0006] Moreover, when setting up the detector array in the existing detector phantom device, it is necessary to configure the corresponding fixing brackets for the detector to support it, which will increase the weight, size, and / or cost of the phantom device. Summary of the Invention

[0007] In view of the above problems, the present utility model provides a global polyhedron detector array - phantom device. This global polyhedron detector array - phantom device has the ability of full - angle dose measurement, is applicable to multi - angle, multi - depth, non - coplanar test items, especially applicable to small radiation field and high - precision test items, avoiding the introduction of additional errors during the test and ignoring the adverse effects on the test results; the phantom device of the present utility model does not need to set the corresponding fixing brackets for the detector, reducing the weight, size, and / or cost of the phantom device.

[0008] The present utility model provides a global polyhedron detector array - phantom device, including: a first sphere 1, a second sphere 2, a detector array 3, and a bracket 4; as Figures 1-4 ; The detector array 3 is used to detect the x - ray signal emitted by the collimator.

[0009] The bracket 4 is used to fix the global polyhedron detector array - phantom device, receive the x - ray signal emitted by the detector array, and transmit it to the control system to convert the x - ray signal into an electrical signal.

[0010] Preferably, the detector array 3 is arranged on the outer surface of the second sphere, and the outer surface of the detector array is connected to the inner surface of the first sphere; one side of the outer surface of the first sphere is connected to the bracket 4.

[0011] Furthermore, the first sphere 1 is a hollow sphere, including a spherical surface one 11 and a spherical surface two 12; the second sphere 2 is a solid sphere.

[0012] The bracket 4 is used to fix the global polyhedron detector array - phantom device, receive the x - ray signal emitted by the detector array, and transmit it to the control system to convert the x - ray signal into an electrical signal.

[0013] The technical solution of the present utility model designs a hollow sphere to wrap the detector array; each detector is closely attached to the inner surface of the hollow sphere to avoid the error of surface dose; a solid sphere is designed to prevent the dosimetric error caused by the backscattering of the rays emitted by the collimator.

[0014] Furthermore, the detector array 3 includes multiple groups of detector units, such as Figure 2 ;

[0015] The technical solution of the present utility model adopts a single - layer global polyhedron detector array, which is more flexible for the irradiation of radiotherapy equipment, has no limitation on the incident direction of the rays, and is especially applicable to the test and verification of small radiation field beams.

[0016] Furthermore, the inner sides of the multiple groups of detector units are arranged in rows in sequence from top to bottom at equal row spacings centered on the z-axis and directly laid on the outer surface of the second sphere, forming a detector array 3 arranged in a spherical manner, capable of performing synchronous detection within the spherical radiation space range;

[0017] Specifically, each group of detector units includes multiple detectors 31, and the multiple detectors 31 are arranged circumferentially at equal spacings centered on the z-axis and directly laid on the outer surface of the second sphere; as Figure 4 ;

[0018] The detector 31 includes a signal receiving surface 311 and a signal transmitting surface 312; the signal receiving surface is in direct contact with the second spherical surface, and the signal transmitting surface is in direct contact with the outer surface of the second sphere; the outer surfaces of the multiple groups of detector units are connected to the inner surface of the spherical surface two 12 and are in contact with the first sphere;

[0019] In an embodiment of the present invention, the detector is an ionization radiation detector, a gas ionization chamber, a liquid ionization chamber or a semiconductor detector.

[0020] The row spacing between adjacent two groups of detector units is equal to the distance between adjacent two detectors in the same group;

[0021] The ratio relationship of the thickness h1 of the hollow sphere to the radius of the spherical surface one 11 and the radius of the spherical surface two 12 is: 2.9:8.1:5.2;

[0022] The ratio relationship of the thickness h1 of the hollow sphere to the radius of the second sphere is: 2.9:3.3;

[0023] The ratio relationship of the detector thickness h2 to the radius of the second sphere is 1.9:3.3;

[0024] Further, the equal row spacing is 0 - 2.47 cm;

[0025] The ratio relationship of the detector thickness to the detector diameter is: 1.9:5 - 10;

[0026] Further, the thickness h1 of the hollow sphere is 2.9 cm;

[0027] The detector thickness h2 is 1.9 cm; the diameter of the detector is 5 - 10 cm;

[0028] Further, the radius of the spherical surface one 11 is 8.1 cm; the radius of the spherical surface two is 5.2 cm;

[0029] The radius of the second sphere is 3.3 cm;

[0030] In one embodiment of the present utility model, the density ratio of the material selected for the first sphere to the material selected for the second sphere is: 1:1;

[0031] The present utility model sets the ratio relationship of the shape dimensions of the two spheres. On the premise of ensuring the measurement accuracy, the size of the entire phantom device can be further reduced; it is set that the row spacing and column spacing of each detector in the detector array are both ≤ 2.47 cm, which can ensure the density of the detectors. The denser the detectors, the higher the actual dose detection accuracy.

[0032] The materials of the first sphere and the second sphere are acrylic;

[0033] It can be understood that the density of the material selected for the first sphere is approximately the same as the density of water, and it is used as a hollow phantom equivalent to water;

[0034] The density of the material selected for the second sphere is approximately the same as the density of water, and it is used as a solid phantom equivalent to water;

[0035] The present utility model selects a solid water-equivalent phantom to approximately equivalent to the patient's body. The important component of human cells is water, and the water content in the human body accounts for 60 - 70% of the human body weight. On the one hand, it meets the requirements of the test items for multi-angle, non-coplanar, and small radiation fields in the project test, and on the other hand, it improves the accuracy of the test.

[0036] In one embodiment of the present utility model, the control member includes a central control system, QA analysis software, and a high-speed power / data interface (PDI);

[0037] The central control system is used to control the detector array, transmit the collected ray signals to the remote software, and perform data analysis on the ray signals based on the remote software; the high-speed power / data interface (PDI) is connected to one side of the central control system, and the high-speed power / data interface (PDI) includes a power interface, a data interface, and an angle indicator light;

[0038] The QA analysis software is used to analyze the difference between the measured ray signal and the planned dose signal;

[0039] The high-speed power / data interface (PDI) is used to supply power to the device and convert communication between the computer and the device.

[0040] The present utility model also provides a method for using a global polyhedron detector array - phantom device, which measures multiple indicators such as the output beam dose stability, the consistency between the laser lamp and the radiation field center, the angle indication accuracy, the accelerator X - ray beam output dose stability corresponding to different mechanical arm mechanical angles, checks the concentricity of the mechanical arm, detects the accelerator radiation field size, radiation field flatness and symmetry, conducts AQA tests, E2E tests, and evaluates the patient plan dose, etc.;

[0041] Preferably, a method for using a global polyhedron detector array - phantom device includes:

[0042] Step 1: Divide multiple mechanical clinical angles to calibrate the spherical detector array - phantom, and obtain the calibrated spherical detector array - phantom;

[0043] Further, the specific steps for obtaining the calibrated spherical detector array - phantom include:

[0044] Divide multiple mechanical angles, irradiate the global polyhedron detector array - phantom by adjusting the mechanical arm of the collimator based on the multiple mechanical clinical angles. The X - ray passes through the first sphere, the detector array, and the second sphere in sequence. Obtain X - ray signals corresponding to the multiple mechanical angles based on the detector array, and store them to obtain multiple stored ray signals;

[0045] Based on the multiple stored ray signals, establish an angle - dose curve graph, and establish a three - dimensional dose distribution according to the angle - dose curve graph;

[0046] Calibrate the first sphere, the second sphere, and the detector array according to the three - dimensional dose distribution to obtain the calibrated first sphere, second sphere, and detector array, that is, obtain the calibrated global polyhedron detector array - phantom;

[0047] Furthermore, the mechanical angles include 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°.

[0048] Step 2: Obtain reference data based on the calibrated global polyhedron detector array - phantom;

[0049] Further, the specific steps for obtaining reference data include:

[0050] Place the calibrated global polyhedron detector array - phantom on the treatment couch, adjust the robotic arm of the collimator to the mechanical 0° position, irradiate the calibrated first sphere, detector array, and second sphere with the collimator in sequence, obtain the x-ray signal based on the detector array, transmit the x-ray signal to the support, transmit the x-ray to the external system based on the support, convert it into the corresponding electrical signal, and store it, which is characterized as reference data for periodic reference detection;

[0051] Step 3: Use the calibrated global polyhedron detector array - phantom to verify the consistency between the laser lamp and the radiation field center, the accuracy of the angle indication, the stability of the X-ray output dose corresponding to the mechanical angles of different collimator robotic arms, measure the concentricity of the robotic arm, verify the radiation field size, flatness, and symmetry of the collimator, conduct automatic quality assurance (AQA) tests, end-to-end (E2E) tests, and evaluate the patient plan dose.

[0052] It can be understood that the accuracy of the angle indication is whether the dose measured at the actual position of the collimator robotic arm is consistent with the system-simulated dose. If it is consistent, it indicates that the mechanical angle of the collimator robotic arm is accurate;

[0053] Furthermore, the specific steps for verifying the consistency between the laser lamp and the radiation field center include:

[0054] Align the laser lamp with the center of the second sphere of the calibrated global polyhedron detector array - phantom to obtain the sphere center;

[0055] Irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom with the collimator robotic arm at the mechanical clinical 0° position to obtain the radiation field center;

[0056] Compare whether the difference between the radiation field center and the second sphere center meets the requirements for the consistency detection of the laser lamp and the radiation field center.

[0057] Furthermore, the specific steps for obtaining the stability of the X-ray output dose corresponding to the mechanical angles of different collimator robotic arms include:

[0058] Irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom with the collimator robotic arm at different mechanical angles with the same dose, obtain the ray signal information corresponding to different mechanical angles and store it, and compare whether the difference in the ray signal information corresponding to different mechanical angles meets the requirements for the stability detection of the X-ray output dose;

[0059] Furthermore, the specific steps for measuring the concentricity of the gantry include:

[0060] Irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom with the collimator robotic arm at a certain mechanical angle, and record it as the first irradiation field center;

[0061] After rotating the collimator robotic arm by 180°, irradiate the second sphere center of the calibrated global polyhedron detector array - phantom to obtain the center of the second irradiation field; compare whether the centers of the first and second irradiation fields coincide and whether they meet the requirements for gantry concentricity detection.

[0062] Further, the specific steps for verifying the collimator radiation field size, radiation field flatness, and symmetry include:

[0063] Set the mechanical angle of the collimator robotic arm to 0°, and irradiate the second sphere of the calibrated global polyhedron detector array - phantom to obtain the radiation field size, radiation field flatness, and symmetry.

[0064] Compare the radiation field size, radiation field flatness, and symmetry with the system information to see if they meet the detection requirements for the collimator radiation field size, radiation field flatness, and symmetry.

[0065] Further, the specific steps for performing the automatic quality assurance (AQA) test include:

[0066] Align the laser lamp with the center of the second sphere of the calibrated global polyhedron detector array - phantom.

[0067] After adjusting the mechanical angle of the collimator robotic arm to 0° and 90°, irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom to obtain the radiation field center at a mechanical angle of 0° and the radiation field center at a mechanical angle of 90°.

[0068] Compare the radiation field center at a mechanical angle of 0° and the radiation field center at a mechanical angle of 90° to see if they meet the requirements for automatic quality assurance detection.

[0069] Further, the specific steps for the end - to - end (E2E) test include:

[0070] Place the calibrated global polyhedron detector array - phantom on the treatment couch for CT scanning to obtain CT image data; execute the end - to - end (E2E) test plan based on the CT image data.

[0071] Irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom with the laser lamp to obtain the sphere center.

[0072] Use the collimator robotic arm to irradiate the second sphere of the calibrated global polyhedron detector array - phantom to obtain the irradiation center.

[0073] Compare the irradiation center and the sphere center to see if they meet the requirements for end - to - end (E2E) test detection.

[0074] Further, the specific steps for evaluating the planned dose of a patient include:

[0075] Set the dose of the patient treatment plan (QA plan),

[0076] Import the patient treatment plan dose into the system to obtain an updated system;

[0077] Place the calibrated global body detector array - phantom on the treatment couch through the bracket 4, execute the patient treatment plan, and obtain the actual dose result;

[0078] Input the actual dose result into the updated system, and make a judgment based on the patient treatment dose detection standard. If the error between the actual dose and the planned dose is less than 1, the actual dose result meets the cycle detection requirements; if the error between the actual dose and the planned dose is greater than 1, the actual dose result does not meet the cycle detection requirements.

[0079] Furthermore, the patient treatment dose detection standard is expressed as:

[0080]

[0081]

[0082] r(r m ,r c ) = |r c - r m |,

[0083] δ(r m ,r c ) = D c (r c ) - D m (r m )

[0084] γ(r m ) > 1, the calculation fails

[0085] γ(r m ) < 1, the calculation passes

[0086] Among them, r m is the m - th actual measurement point in space; r c is the c - th planned measurement point in space; γ(r m ) is the exponential result of the m - th actual measurement point; Dc(rc): the dose at the position corresponding to the c - th planned measurement point; Dm(r m ): the dose at the position corresponding to the m - th actual measurement point; δ(r m ,r c):The difference between the dose at the position corresponding to the c-th planned measurement point and the dose at the position corresponding to the m-th actual measurement point; c = 1, 2, 3... C, where C represents the total number of planned measurement points, and m = 1, 2, 3... M, where M represents the total number of actual measurement points.

[0087] When the phantom device of the present utility model is applied to the treatment of a patient's tumor target area, it assists the collimator to adjust the size of the treatment target area according to the size of the tumor target area, ensuring that the size of the treatment target area conforms to the size of the patient's tumor. It is especially suitable for accurately positioning and measuring the tumor target area when using a small radiation field collimator for treatment (tumor ≤ 3 cm), ensuring the treatment effect and safety.

[0088] Compared with the prior art, the present utility model has at least the following beneficial effects:

[0089] (1) The phantom device of the present utility model detects and verifies multiple stereotactic radiotherapy indicators, realizing the actual measurement of the global surface, multi-angle, and small radiation field of the stereotactic radiotherapy equipment; at the same time, there is no need to set up a corresponding fixed bracket for the detector, reducing the weight, size, and / or cost of the phantom device;

[0090] (2) The present utility model obtains multiple X-ray signal data through the global surface detector array, and calculates the dose through fitting of the multiple X-ray signal data, reducing the influence error caused by the fitting difference dose;

[0091] (3) The operation process of the phantom device of the present utility model is simple, and all tests can be completed with one setup. Description of the Drawings

[0092] The drawings are only for the purpose of illustrating specific embodiments and are not considered to be a limitation of the present utility model.

[0093] Figure 1 It is a schematic diagram of the first sphere and the bracket in the global surface detector array - phantom in the embodiment of the present utility model;

[0094] Figure 2 It is a schematic diagram of the detector array in the global surface detector array - phantom in the embodiment of the present utility model;

[0095] Figure 3 It is a schematic diagram of the cross-sectional view of the global surface detector array - phantom in the embodiment of the present utility model;

[0096] Figure 4 It is a schematic diagram of the cross-sectional view of the detector array unit of the global surface detector array - phantom in the embodiment of the present utility model;

[0097] Reference Numerals:

[0098] 1 - First sphere, 11 - First spherical surface, 12 - Second spherical surface, 2 - Second sphere, 3 - Detector array, 31 - Detector, 4 - Bracket. Detailed implementation mode

[0099] In order to more clearly understand the above - mentioned objects, features, and advantages of the present utility model, the present utility model will be further described in detail below with reference to the drawings and specific implementation modes. It should be noted that, without conflict, the embodiments of the present utility model and the features in the embodiments can be combined with each other. In addition, the present utility model can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present utility model is not limited by the specific embodiments disclosed below.

[0100] A specific embodiment of the present utility model, as Figures 1-4 , discloses a global spherical surface detector array - phantom device. In order to illustrate the effectiveness of the method proposed by the present utility model, the above - mentioned technical solutions of the present utility model will be described in detail below through a specific embodiment. The specific implementation steps are as follows:

[0101] It includes: a first sphere 1, a second sphere 2, a detector array 3, and a bracket 4; as Figures 1-4 ; the detector array 3 is used to detect the x - ray signals emitted by the collimator;

[0102] The bracket 4 is used to fix the global spherical surface detector array - phantom device, receive the x - ray signals emitted by the detector array, and transmit them to the control system to convert the x - ray signals into electrical signals;

[0103] Preferably, the detector array 3 is arranged on the outer surface of the second sphere, and the outer surface of the detector array is connected to the inner surface of the first sphere; one side of the outer surface of the first sphere is connected to the bracket 4;

[0104] Further, the first sphere 1 is a hollow sphere, including a first spherical surface 11 and a second spherical surface 12; the second sphere 2 is a solid sphere;

[0105] The bracket 4 is used to fix the global spherical surface detector array - phantom device, receive the x - ray signals emitted by the detector array, and transmit them to the control system to convert the x - ray signals into electrical signals;

[0106] The technical solution of the present utility model designs a hollow sphere to wrap the detector array; each detector is closely attached to the inner surface of the hollow sphere to avoid the error of surface dose; a solid sphere is designed to prevent the dosimetric error caused by the backscattering of the rays emitted by the collimator.

[0107] Further, the detector array 3 includes multiple groups of detector units, as Figure 2 ;

[0108] The technical solution of the present utility model adopts a single-layer global surface detector array, which is more flexible for the irradiation of radiotherapy equipment, has no limitation on the incident direction of rays, and is especially suitable for the test and verification of small radiation field beams.

[0109] Furthermore, the inner sides of the multiple groups of detector units are arranged in rows in sequence from top to bottom at equal row spacings centered on the z-axis and directly laid on the outer surface of the second sphere, forming a detector array 3 arranged in a spherical manner, capable of performing synchronous detection within the spherical radiation space range;

[0110] Specifically, each group of detector units includes a plurality of detectors 31, and the plurality of detectors 31 are arranged circumferentially at equal intervals centered on the z-axis and directly laid on the outer surface of the second sphere; as Figure 4 ;

[0111] The detector 31 includes a signal receiving surface 311 and a signal transmitting surface 312; the signal receiving surface directly contacts the second spherical surface, and the signal transmitting surface directly contacts the outer surface of the second sphere. In an embodiment of the present utility model, the detector is an ionization radiation detector, a gas ionization chamber, a liquid ionization chamber or a semiconductor detector.

[0112] The row spacing between adjacent two groups of detector units is equal to the distance between adjacent two detectors in the same group;

[0113] The ratio relationship of the thickness h1 of the hollow sphere to the radius of the spherical surface one 11 and the radius of the spherical surface two 12 is: 2.9:8.1:5.2;

[0114] The ratio relationship of the thickness h1 of the hollow sphere to the radius of the second sphere is: 2.9:3.3;

[0115] The ratio relationship of the detector thickness h2 to the radius of the second sphere is 1.9:3.3;

[0116] Further, the equal row spacing is 0 - 2.47 cm;

[0117] The ratio relationship of the detector thickness to the detector diameter is: 1.9:5 - 10;

[0118] Further, the thickness h1 of the hollow sphere is 2.9 cm;

[0119] The detector thickness h2 is 1.9 cm; the diameter of the detector is 5 - 10 cm;

[0120] Further, the radius of the spherical surface one 11 is 8.1 cm; the radius of the spherical surface two is 5.2 cm;

[0121] The radius of the second sphere is 3.3 cm;

[0122] In one embodiment of the present utility model, the density ratio of the material selected for the first sphere to the material selected for the second sphere is: 1:1;

[0123] The present utility model sets the ratio relationship of the shape dimensions of the two spheres. On the premise of ensuring the measurement accuracy, the size of the entire phantom device can be further reduced; it is set that the row spacing and the column spacing of each detector in the detector array are both ≤ 2.47 cm, which can ensure the density of the detectors. The denser the detectors, the higher the actual dose detection accuracy.

[0124] The materials of the first sphere and the second sphere are acrylic;

[0125] It can be understood that the density of the material selected for the first sphere is approximately the same as the density of water, and it is used as a hollow phantom equivalent to water;

[0126] The density of the material selected for the second sphere is approximately the same as the density of water, and it is used as a solid phantom equivalent to water;

[0127] The present utility model selects a solid water-equivalent phantom which is approximately equivalent to the patient's body. The important component of human cells is water, and the water content in the human body accounts for 60 - 70% of the human body weight. On the one hand, it meets the requirements of the test items for multi-angle, non-coplanar, and small radiation fields in the project test, and on the other hand, it improves the accuracy of the test.

[0128] In one embodiment of the present utility model, the control member includes a central control system, QA analysis software, and a high-speed power / data interface (PDI);

[0129] The central control system is used to control the detector array, transmit the collected ray signals to the remote software, and perform data analysis on the ray signals based on the remote software; the high-speed power / data interface (PDI) is connected to one side of the central control system, and the high-speed power / data interface (PDI) includes a power interface, a data interface, and an angle indicator light;

[0130] The QA analysis software is used to analyze the difference between the measured ray signal and the planned dose signal;

[0131] The high-speed power / data interface (PDI) is used to supply power to the device and convert communication between the computer and the device.

[0132] The present utility model further provides a method for using a global polyhedron detector array - phantom device, which measures multiple indicators such as the output beam dose stability, the consistency between the laser lamp and the radiation field center, the angle indication accuracy, the accelerator X - ray beam output dose stability corresponding to different mechanical arm mechanical angles, checking the concentricity of the mechanical arm, detecting the accelerator radiation field size, radiation field flatness and symmetry, conducting AQA tests, E2E tests, and evaluating the patient plan dose, etc.;

[0133] Preferably, a method for using a global polyhedron detector array - phantom device includes:

[0134] Step 1: Divide multiple mechanical clinical angles to calibrate the spherical detector array - phantom, and obtain the calibrated spherical detector array - phantom;

[0135] Further, the specific steps for obtaining the calibrated spherical detector array - phantom include:

[0136] Divide multiple mechanical angles, irradiate the global polyhedron detector array - phantom by adjusting the mechanical arm of the collimator based on the multiple mechanical clinical angles. The X - ray passes through the first sphere, the detector array, and the second sphere in sequence. Obtain the X - ray signals corresponding to multiple mechanical angles based on the detector array, and store them to obtain multiple stored ray signals;

[0137] Based on the multiple stored ray signals, establish an angle - dose curve graph, and establish a three - dimensional dose distribution according to the angle - dose curve graph;

[0138] Calibrate the first sphere, the second sphere, and the detector array according to the three - dimensional dose distribution to obtain the calibrated first sphere, second sphere, and detector array, that is, obtain the calibrated global polyhedron detector array - phantom;

[0139] Furthermore, the mechanical angles include 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°.

[0140] Step 2: Obtain reference data based on the calibrated global polyhedron detector array - phantom;

[0141] Further, the specific steps for obtaining reference data include:

[0142] Place the calibrated global polyhedron detector array - phantom on the treatment couch, adjust the robotic arm of the collimator to the mechanical 0° position, and use the collimator to irradiate the calibrated first sphere, detector array, and second sphere in sequence. Obtain the x-ray signal based on the detector array, transmit the x-ray signal to the support, transmit the x-ray to the external system based on the support, convert it into the corresponding electrical signal, and store it, which is characterized as reference data for periodic reference detection.

[0143] Step 3: Use the calibrated global polyhedron detector array - phantom to verify the consistency between the laser light and the radiation field center, the accuracy of the angle indication, the stability of the X-ray output dose corresponding to the mechanical angles of different collimator robotic arms, measure the concentricity of the robotic arm, verify the radiation field size, flatness, and symmetry of the collimator, conduct automatic quality assurance (AQA) tests, end-to-end (E2E) tests, and evaluate the patient planned dose.

[0144] It can be understood that the accuracy of the angle indication is whether the dose measured at the actual position of the collimator robotic arm is consistent with the system-simulated dose. If they are consistent, it indicates that the mechanical angle of the collimator robotic arm is accurate.

[0145] Furthermore, the specific steps for verifying the consistency between the laser light and the radiation field center include:

[0146] Align the laser light with the center of the second sphere of the calibrated global polyhedron detector array - phantom to obtain the sphere center.

[0147] Irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom with the collimator robotic arm at the mechanical clinical 0° position to obtain the radiation field center.

[0148] Compare whether the difference between the radiation field center and the second sphere center meets the requirements for the consistency detection of the laser light and the radiation field center.

[0149] Furthermore, the specific steps for obtaining the stability of the X-ray output dose corresponding to the mechanical angles of different collimator robotic arms include:

[0150] Irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom with the collimator robotic arm at different mechanical angles with the same dose, obtain and store the ray signal information corresponding to different mechanical angles, and compare whether the differences in the ray signal information corresponding to different mechanical angles meet the requirements for the X-ray output dose stability detection.

[0151] Furthermore, the specific steps for measuring the concentricity of the gantry include:

[0152] Irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom with the collimator robotic arm at a certain mechanical angle, and record it as the first irradiation field center.

[0153] After rotating the collimator robotic arm by 180°, irradiate the second sphere center of the calibrated global polyhedron detector array - phantom to obtain the center of the second irradiation field; compare whether the centers of the first and second irradiation fields coincide and whether they meet the requirements for gantry concentricity detection.

[0154] Further, the specific steps for verifying the collimator radiation field size, radiation field flatness, and symmetry include:

[0155] Set the mechanical angle of the collimator robotic arm to 0°, and irradiate the second sphere of the calibrated global polyhedron detector array - phantom to obtain the radiation field size, radiation field flatness, and symmetry;

[0156] Compare the radiation field size, radiation field flatness, and symmetry with the system information to see if they meet the detection requirements for the collimator radiation field size, radiation field flatness, and symmetry.

[0157] Further, the specific steps for performing the automatic quality assurance (AQA) test include:

[0158] Align the laser lamp with the center of the second sphere of the calibrated global polyhedron detector array - phantom,

[0159] After adjusting the mechanical angle of the collimator robotic arm to 0° and 90°, irradiate the center of the second sphere of the calibrated global polyhedron detector array - phantom to obtain the radiation field center at a mechanical angle of 0° and the radiation field center at a mechanical angle of 90°;

[0160] Compare the radiation field center at a mechanical angle of 0° and the radiation field center at a mechanical angle of 90° to see if they meet the requirements for automatic quality assurance detection.

[0161] Further, the specific steps for the end - to - end (E2E) test include:

[0162] Place the calibrated global polyhedron detector array - phantom on the treatment couch for CT scanning to obtain CT image data; execute the end - to - end (E2E) test plan based on the CT image data;

[0163] Shine the laser lamp on the center of the second sphere of the calibrated global polyhedron detector array - phantom to obtain the sphere center;

[0164] Use the collimator robotic arm to irradiate the second sphere of the calibrated global polyhedron detector array - phantom to obtain the irradiation center;

[0165] Compare the irradiation center and the sphere center to see if they meet the requirements for end - to - end (E2E) test detection.

[0166] Further, the specific steps for evaluating the planned dose of a patient include:

[0167] Set the dose of the patient's treatment plan (QA plan),

[0168] Import the patient treatment plan dose into the system to obtain an updated system;

[0169] Place the calibrated global body detector array - phantom on the treatment couch through the bracket 4, execute the patient treatment plan, and obtain the actual dose result;

[0170] Input the actual dose result into the updated system, and make a judgment based on the patient treatment dose detection standard. If the error between the actual dose and the planned dose is less than 1, the actual dose result meets the cycle detection requirements; if the error between the actual dose and the planned dose is greater than 1, the actual dose result does not meet the cycle detection requirements.

[0171] Furthermore, the patient treatment dose detection standard is expressed as:

[0172]

[0173]

[0174] r(r m , r c ) = |r c - r m |,

[0175] δ(r m , r c ) = D c (r c ) - D m (r m )

[0176] γ(r m ) > 1, calculation fails

[0177] γ(r m ) < 1, calculation passes

[0178] Where r m is the m - th actual measurement point in space; r c is the c - th planned measurement point in space; γ(r m ) is the exponential result of the m - th actual measurement point; Dc(rc): the dose at the position corresponding to the c - th planned measurement point; Dm(r m ): the dose at the position corresponding to the m - th actual measurement point; δ(r m , r c):The difference between the dose at the position corresponding to the c-th planned measurement point and the dose at the position corresponding to the m-th actual measurement point; c = 1, 2, 3... C, where C represents the total number of planned measurement points, and m = 1, 2, 3... M, where M represents the total number of actual measurement points.

[0179] When the phantom device of the present utility model is applied to the treatment of the tumor target area of a patient, it assists in adjusting the size of the treatment target area according to the size of the tumor target area, ensuring that the size of the treatment target area conforms to the size of the patient's tumor. It is especially suitable for accurately positioning and measuring the tumor target area when using a small radiation field collimator for treatment (tumor ≤ 3 cm), ensuring the treatment effect and safety.

[0180] The above is only the preferred specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered within the protection scope of the present utility model.

Claims

1. A global polyhedron detector array - phantom device, characterized in that, It includes a first sphere (1), a second sphere (2), and a detector array (3); The first sphere (1) is a hollow sphere; the second sphere (2) is a solid sphere; The detector array is respectively connected to the first sphere and the second sphere; the detector array (3) includes multiple groups of detector units; The multiple groups of detector units are arranged in rows in sequence from top to bottom on the outer surface of the second sphere, forming a detector array arranged in a spherical manner.

2. The global polyhedron detector array - phantom device according to claim 1, wherein, The first sphere includes a first spherical surface (11) and a second spherical surface (12); the first spherical surface is located on the outside of the first sphere; the second spherical surface is located on the inside of the first sphere; The multiple groups of detector units are respectively in contact with the inside of the second spherical surface (12) and the outside of the second sphere.

3. The global polyhedron detector array - phantom device according to claim 2, wherein, The proportional relationship among the thickness of the first sphere, the radius of the first spherical surface, and the radius of the second spherical surface is: 2.9:8.1:5.2。 4. The global polyhedron detector array - phantom device according to claim 3, wherein, The proportional relationship between the thickness of the first sphere and the radius of the second sphere is: 2.9:3.3。 5. The global hexahedron detector array - phantom device according to claim 3, wherein The inner sides of the multiple groups of detector units are arranged in rows in sequence from top to bottom on the outer surface of the second sphere according to the same row spacing.

6. The global hexahedron detector array - phantom device according to claim 3, characterized in that Each group of detector units includes multiple detectors (31); the multiple detectors (31) are arranged circumferentially at equal intervals; The detector (31) includes a signal receiving surface (311) and a signal transmitting surface (312); the signal receiving surface is in direct contact with the second spherical surface, and the signal transmitting surface is in direct contact with the outer surface of the second sphere.

7. The global hexahedron detector array - phantom device according to claim 6, wherein The row spacing between two adjacent groups of detector units in the multiple groups of detector units is equal to the distance between two adjacent detectors in the same group.

8. The global hexahedral detector array - phantom device according to claim 3, characterized in that, The proportional relationship between the thickness (h2) of the detector (31) and the radius of the second sphere is 1.9:3.

3.

9. The global polyhedron detector array-mold device according to claim 1, characterized in that, The detector (31) is an ionization radiation detector, a gas ionization chamber, a liquid ionization chamber, or a semiconductor detector.

10. The global polyhedron detector array - phantom device according to claim 1, wherein, The proportional relationship between the density of the first sphere and the density of the second sphere is: 1:1.

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