A particle source dose distribution measuring device and a measuring method

Abstract

The particle source dose distribution measurement device and method provided in this application include a chassis, a mounting bracket, and multiple measuring brackets. The mounting bracket has a first mounting portion for mounting a particle source. Multiple measuring brackets are mounted on the chassis, spaced apart around the periphery of the mounting bracket, and each bracket is radially movable to move away from or towards the mounting bracket. Each measuring bracket has a second mounting portion for mounting a passive dosimeter. The positions of the first and second mounting portions satisfy the following condition: when the particle source is mounted on the first mounting portion and the passive dosimeter is mounted on the second mounting portion, the passive dosimeter is aligned with the center of the particle source. The particle source dose distribution measurement device of this application can improve the accuracy of particle source dose distribution measurement.

Description

Technical Field

[0001] This application relates to the field of medical radiotherapy technology, and in particular to a device and method for measuring particle source dose distribution. Background Technology

[0002] 125 I-type particle sources have been widely used in the radiotherapy of various types of solid tumors because their radiation characteristics meet the requirements of particle implantation therapy. The accuracy of the dose distribution around the particle source during treatment directly affects the treatment effect.

[0003] In related technologies, passive dosimeters (thermoluminescent or optically stimulated luminescence dosimeters) are commonly used to measure the dose distribution of particle sources. However, since the relative position of the passive dosimeter and the particle source in the measuring device is fixed, the accuracy of the particle source dose distribution measurement is reduced. Summary of the Invention

[0004] In view of this, the embodiments of this application aim to provide a particle source dose distribution measurement device and measurement method that can improve the accuracy of particle source dose distribution measurement.

[0005] To achieve the above objectives, embodiments of this application provide a particle source dose distribution measurement device, comprising:

[0006] Chassis;

[0007] The mounting bracket is provided with a first mounting part, which is used to mount a particle source.

[0008] Multiple measuring brackets are mounted on the chassis, and each measuring bracket is spaced apart around the mounting bracket. Each measuring bracket can move radially along the chassis to move away from or closer to the mounting bracket. Each measuring bracket is provided with a second mounting part for mounting a passive dosimeter.

[0009] The positions of the first mounting part and the second mounting part satisfy the following condition: when the particle source is mounted on the first mounting part and the passive dosimeter is mounted on the second mounting part, the passive dosimeter is aligned with the center of the particle source.

[0010] In one embodiment, each of the measuring brackets is slidably mounted on the chassis.

[0011] In one embodiment, the chassis is provided with a plurality of sliding grooves corresponding to the plurality of measuring brackets, each sliding groove extending radially along the chassis, and the plurality of measuring brackets being slidably disposed in the corresponding plurality of sliding grooves.

[0012] In one embodiment, the sidewall of the slide groove is recessed to form a limiting groove, each measuring bracket includes a rod and a limiting part connected to the rod, the second mounting part is disposed on the rod, and the limiting part is located in the limiting groove to limit the measuring bracket.

[0013] In one embodiment, each of the grooves extends through the outer side wall of the chassis.

[0014] In one embodiment, each of the measuring brackets is arranged circumferentially around the center of the mounting bracket.

[0015] In one embodiment, the mounting bracket is rotatably mounted relative to the chassis.

[0016] In one embodiment, a through hole is provided at the center of the chassis, and the mounting bracket passes through the through hole.

[0017] In one embodiment, the mounting bracket includes a first bracket, and the first mounting portion is a plug hole formed on the top of the first bracket and extending along the length direction of the first bracket, for inserting the particle source into the plug hole along the length direction.

[0018] In one embodiment, the mounting bracket includes a second bracket having the first mounting portion, and the particle source is placed horizontally on the first mounting portion.

[0019] In one embodiment, the first mounting part consists of a mounting post, a hanging lug, and an elastic cord disposed on the second bracket. The particle source is placed horizontally on the mounting post, and the elastic cord cooperates with the hanging lug to fix the particle source.

[0020] In one embodiment, each of the measuring brackets can move within a range of at least 1cm-10cm from the mounting bracket.

[0021] This application embodiment also provides a method for measuring particle source dose distribution, applied to the above-described measuring device, characterized in that the measurement method includes:

[0022] The particle source is placed on the mounting bracket along the first direction;

[0023] Each passive dosimeter is mounted on a plurality of measuring brackets, which are arranged in a circumferential direction around the center of the mounting brackets;

[0024] The mounting bracket is controlled to rotate relative to the chassis, and the particle source is measured within a preset time.

[0025] The distance between each of the measuring brackets and the mounting bracket is changed, and the particle source is measured within a preset time.

[0026] In one embodiment, after the step of changing the distance between each of the measuring supports and the mounting support to measure the particle source within a preset time, the method further includes:

[0027] The particle source is placed on the mounting bracket along the second direction, wherein the first direction is perpendicular to the second direction;

[0028] The mounting bracket is controlled to rotate relative to the chassis, and the particle source is measured within a preset time.

[0029] The distance between each of the measuring brackets and the mounting bracket is changed, and the particle source is measured within a preset time.

[0030] In one embodiment, the preset time is 1.5h-2.5h.

[0031] The particle source dose distribution measurement device provided in this application embodiment, by setting multiple measurement supports on the chassis, with each measurement support spaced apart around the periphery of the mounting support, allows passive dosimeters to be placed in multiple directions of the particle source, enabling simultaneous multi-angle measurement of the particle source dose distribution. Furthermore, each measurement support can move radially along the chassis to move away from or closer to the mounting support, meaning the measurement distance can be continuously adjusted by adjusting the distance between each measurement support and the mounting support. In other words, by adjusting the measurement distance and using multiple measurement angles to measure the particle source dose distribution, a more comprehensive particle source dose distribution database can be obtained. This allows for the creation of a relative dose contour map using a large amount of measurement data, which helps users assess the placement of the particle source and improves the accuracy of particle source dose distribution measurement. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of a particle source dose distribution measuring device according to an embodiment of this application;

[0033] Figure 2 for Figure 1 The diagram shows the structural design of the chassis.

[0034] Figure 3 This is a schematic diagram of the structure of the measuring bracket according to an embodiment of this application;

[0035] Figure 4 This is a schematic diagram of the structure of the first support in an embodiment of this application;

[0036] Figure 5 This is a schematic diagram of the structure of the second bracket according to an embodiment of this application;

[0037] Figure 6 This is a schematic diagram of the polar coordinates used in this application for calculating particle source dosimetry parameters;

[0038] Figure 7 This is a flowchart of a method for measuring particle source dose distribution in an embodiment of this application.

[0039] Explanation of reference numerals in the attached figures

[0040] Chassis 10; sliding groove 10a; limiting groove 10b; through hole 10c; mounting bracket 20; first mounting part 20a; first bracket 21; insertion hole 21a; second bracket 22; mounting post 221; hanging lug 222; measuring bracket 30; second mounting part 30a; rod part 30b; limiting part 30c; measuring device 100. Detailed Implementation

[0041] It should be noted that, unless otherwise specified, the embodiments and technical features in the embodiments of this application can be combined with each other, and the detailed descriptions in the specific implementation should be understood as explanations of the purpose of this application and should not be regarded as undue limitations on this application.

[0042] One embodiment of this application provides a device for measuring particle source dose distribution. Please refer to [link to relevant documentation]. Figures 1 to 5 The measuring device 100 includes a chassis 10, a mounting bracket 20, and multiple measuring brackets 30. The measuring device 100 is suitable for measuring particle source dose distribution using a passive dosimeter.

[0043] The specific shape of the chassis 10 is not limited here. For example, it can be circular, elliptical, polygonal or irregular. In this embodiment, the chassis 10 is described as circular.

[0044] The mounting bracket 20 is provided with a first mounting part 20a, which is used to mount the particle source, that is, the mounting bracket 20 is used to mount the particle source.

[0045] Please see Figure 3 The measuring bracket 30 is provided with a second mounting part 30a, which is used to install a passive dosimeter. That is, the measuring bracket 30 is provided to install a passive dosimeter.

[0046] Please see Figure 1 In this embodiment of the application, a plurality of measuring brackets 30 are provided, which are mounted on the chassis 10. Each measuring bracket 30 is spaced apart on the periphery of the mounting bracket 20, that is, each measuring bracket 30 surrounds the periphery of the mounting bracket 20, so that a passive dosimeter is provided on the periphery of the particle source.

[0047] It should be noted that "multiple" refers to a quantity of 2 or more, such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20, etc. In this embodiment, the measurement bracket 30 is described as having a quantity of 8.

[0048] In one specific embodiment, please refer to Figure 1 There are 8 measuring brackets 30, which are arranged in a circumferential direction around the center of the mounting bracket 20, and the central angle between any two adjacent measuring brackets 30 is 45°.

[0049] Each measuring bracket 30 can move radially along the chassis 10 to move away from or closer to the mounting bracket 20, that is, each measuring bracket 30 can move radially along the chassis 10, which is beneficial for adjusting the distance between each measuring bracket 30 and the mounting bracket 20.

[0050] The positions of the first mounting part 20a and the second mounting part 30a satisfy the following condition: when the particle source is mounted on the first mounting part 20a and the passive dosimeter is mounted on the second mounting part 30a, the passive dosimeter is aligned with the center of the particle source, that is, the passive dosimeter and the center of the particle source are at the same height.

[0051] The particle source dose distribution measuring device provided in this application embodiment, by setting multiple measuring supports 30 on the chassis 10, with each measuring support 30 spaced apart around the mounting bracket 20, allows passive dosimeters to be set in multiple directions of the particle source, enabling simultaneous multi-angle measurement of the particle source dose distribution. Furthermore, each measuring support 30 can move radially along the chassis 10 to move away from or closer to the mounting bracket 20, meaning the measurement distance can be continuously adjusted by adjusting the distance between each measuring support 30 and the mounting bracket 20. In other words, the measuring device 100 of this application embodiment can obtain a more comprehensive particle source dose distribution database by adjusting the measurement distance and using multiple measurement angles to measure the particle source dose distribution. This allows for the use of a large amount of measurement data to create a relative dose contour map, which helps users assess the placement of the particle source and improves the accuracy of particle source dose distribution measurement.

[0052] The mounting bracket 20 is rotatable relative to the chassis 10. Exemplarily, in one embodiment, the chassis 10 may be stationary during measurement, while the mounting bracket 20 may be rotatable. Thus, by rotating the mounting bracket 20, the particle source can be rotated relative to the chassis 10, thereby obtaining a dose distribution within the 0°-360° range of the particle source.

[0053] In other embodiments, during the measurement process, the chassis 10 may be rotatable, while the mounting bracket 20 may be non-rotatable. Thus, by rotating the chassis 10, the particle source can be rotated relative to the chassis 10, thereby obtaining the dose distribution of the particle source within the range of 0°-360°. Rotating the chassis 10 does not change the position of the particle source, further improving the accuracy of the measured particle source dose distribution.

[0054] In some other embodiments, during the measurement process, the chassis 10 can be rotatable, and the mounting bracket 20 can also be rotatable. In this way, by rotating the chassis 10, or rotating the mounting bracket 20, or rotating the mounting bracket 20 and the chassis 10 at the same time, the particle source can be rotated relative to the chassis 10, thereby obtaining the dose distribution of the particle source within the range of 0°-360°.

[0055] It should be noted that the specific structure of the mounting bracket 20, which is rotatable relative to the chassis 10, is not limited. For example, please refer to [link to relevant documentation]. Figure 1 and Figure 2 A through hole 10c is provided at the center of the chassis 10, and the mounting bracket 20 passes through the through hole 10c. The particle source is placed in the first mounting part 20a. In this way, the mounting bracket 20 can rotate relative to the chassis 10, so that the particle source can rotate relative to the chassis 10.

[0056] A motor can be connected to the bottom of the mounting bracket 20 or the chassis 10 to achieve uniform rotation of the mounting bracket 20 or the chassis 10. Of course, the mounting bracket 20 or the chassis 10 can also be rotated manually.

[0057] In one embodiment, each measuring bracket 30 is slidably mounted on the chassis 10, meaning the measuring bracket 30 and the chassis 10 are in sliding engagement. During the measurement process, the measuring bracket 30 can slide on the chassis 10 to adjust the distance between each measuring bracket 30 and the mounting bracket 20, that is, to adjust the distance between the passive dosimeter and the particle source. In this way, the measurement distance can be continuously adjusted, and the radial dose distribution of the particle source can be measured.

[0058] The specific manner in which each measuring bracket 30 slides into the chassis 10 is not limited here. For example, in one embodiment, please refer to... Figure 1 and Figure 2 The chassis 10 is provided with multiple sliding grooves 10a corresponding to multiple measuring brackets 30. Each sliding groove 10a extends radially along the chassis 10. The multiple measuring brackets 30 are slidably disposed in the corresponding multiple sliding grooves 10a. That is, by providing sliding grooves 10a corresponding to each measuring bracket 30 on the chassis 10, each measuring bracket 30 is disposed in the sliding groove 10a and slides in cooperation with the chassis 10.

[0059] Each slide groove 10a extends radially along the chassis 10, that is, each slide groove 10a is arranged radially on the chassis 10, and each measuring bracket 30 can slide radially along the chassis 10 to move away from or close to the mounting bracket 20.

[0060] In other embodiments, the chassis 10 is provided with a plurality of limiting ribs corresponding to a plurality of measuring brackets 30. Each limiting rib extends radially along the chassis 10. Each measuring bracket 30 is provided with a groove corresponding to the limiting rib. The limiting rib and the groove cooperate to allow each measuring bracket 30 to be slidably disposed in the corresponding slide groove 10a.

[0061] In one embodiment, please refer to Figure 1 and Figure 2 The sidewall of the slide groove 10a is recessed to form a limiting groove 10b, which extends along the extension direction of the slide groove 10a. Each measuring bracket 30 includes a rod portion 30b and a limiting portion 30c connected to the rod portion 30b. The second mounting portion 30a is disposed on the rod portion 30b, and the limiting portion 30c is located in the limiting groove 10b to limit the measuring bracket 30. That is, by setting the limiting groove 10b, and by setting the limiting portion 30c, when the measuring bracket 30 is disposed on the chassis 10, the limiting portion 30c is located in the limiting groove 10b to limit the measuring bracket 30, thereby preventing the measuring bracket 30 from falling out of the slide groove 10a and improving the structural reliability of the measuring device 100.

[0062] For example, the measuring bracket 30 is provided with mounting holes, and the measuring device 100 includes a mounting box. The size of the mounting box can be designed according to the size of the passive dosimeter. The passive dosimeter is placed in the mounting box, and the mounting box is placed at the mounting hole of the measuring bracket 30 to complete the assembly of the passive dosimeter.

[0063] The specific location of the limiting groove 10b is not limited here. For example, the limiting groove 10b can be formed at the bottom of the slide groove 10a or in the middle of the slide groove 10a, as long as it can restrict the measuring bracket 30 from coming out of the slide groove 10a. It should be noted that the restriction of the measuring bracket 30 from coming out of the slide groove 10a refers to coming out in a direction perpendicular to the plane of the chassis 10, and does not restrict the measuring bracket 30 from moving radially along the chassis 10 or coming out of the slide groove 10a radially along the chassis 10.

[0064] In one embodiment, please refer to Figure 1 and Figure 2 Each groove 10a penetrates the outer side wall of the chassis 10, that is, the groove 10a is formed on the outer side wall of the chassis 10 and extends radially along the chassis 10. In this way, each measuring bracket 30 can be inserted into the groove 10a from the outside of the chassis 10, which is beneficial to the assembly of the measuring bracket 30.

[0065] Of course, each groove 10a may also be a blind end that does not penetrate the outer wall of the chassis 10, that is, the outer side of the groove 10a along the radial direction of the chassis 10 is a blind end.

[0066] In one embodiment, each measuring bracket 30 can move within a range of 1cm to 10cm from the mounting bracket 20. The distance between each measuring bracket 30 and the mounting bracket 20 is, for example, 1cm, 1.5cm, 2cm, 3cm, 4cm, 5cm, 6cm, 6.5cm, 7cm, 8cm, 9cm, or 10cm.

[0067] In other words, the distance between the passive dosimeter and the particle source can be adjusted from 1cm to 10cm, thus enabling continuous adjustment of the measurement distance and measurement of the radial dose distribution of the particle source.

[0068] In one embodiment, please refer to Figure 1 and Figure 2 Each measuring bracket 30 is arranged along the circumference of the center of the mounting bracket 20, that is, each measuring bracket 30 is located on the circumference of the same circle with the center of the mounting bracket 20 as the center.

[0069] The specific structure of the mounting bracket 20 is not limited here. For example, in one embodiment, please refer to [reference needed]. Figure 4 The mounting bracket 20 includes a first bracket 21 and a first mounting part 20a, which is a plug hole 21a formed on the top of the first bracket 21 and extending along the length direction of the first bracket 21. The plug hole 21a is used to insert the particle source into the plug hole 21a along the length direction, that is, the particle source can be placed on the first mounting part 20a in the vertical direction.

[0070] By placing the particle source vertically on the first mounting portion 20a of the first support 21, the radial dose distribution of the particle source can be measured.

[0071] Specifically, the insertion hole 21a can be located at the center of the first support 21. The particle source is first placed in the polyimide thin tube (wall thickness 0.03mm, inner diameter 0.8mm), and then the polyimide tube is inserted into the insertion hole 21a.

[0072] In other embodiments, please refer to Figure 5 The mounting bracket 20 includes a second bracket 22 with a first mounting part 20a, and the particle source is placed horizontally on the first mounting part 20a.

[0073] Specifically, the first mounting part 20a consists of a mounting post 221, a hanging lug 222, and a tension rope mounted on the second bracket 22. The particle source is placed horizontally on the mounting post 221, and the tension rope and the hanging lug 222 cooperate to fix the particle source. The particle source is first placed in a polyimide tube, which is then placed horizontally on the mounting post 221. The tension rope and the hanging lug 222 cooperate to fix the polyimide tube, thereby fixing the particle source.

[0074] By placing the particle source horizontally on the first mounting part 20a of the second support 22, the two-dimensional dose distribution of the particle source can be measured.

[0075] The measuring device 100 in this embodiment is designed to allow for arbitrary adjustment of angle and distance when measuring the particle source dose distribution using a passive dosimeter.

[0076] 125 I-particle sources, due to their radiation characteristics meeting the requirements of particle implantation therapy, have been widely used in radiotherapy for various types of solid tumors. The accuracy of the dose distribution around the particle source during treatment directly affects the therapeutic effect. Therefore, dose distribution is an urgent problem to be solved in clinical radiotherapy. The American Association of Medical Physicists (AAPM) has successively published TG 43 and TG 43-U1 reports, clarifying the mathematical models of particle source dosimetry parameters and the relevant parameters of several common particle sources. However, due to differences in particle source geometry and manufacturing processes, the dose distribution at the lesion site will also differ. According to the TG 43-U1 report, in the formulas for calculating the one-dimensional and two-dimensional dose distribution of a particle source, the particle source dose rate constant Λ is an absolute quantity, and the geometric function G... L (r,θ), radial dose function g L (r), one-dimensional anisotropic function φ an (r) and the two-dimensional anisotropic function F(r,θ) are relative quantities. Please refer to [link to relevant documentation]. Figure 6 The reference point (r0, θ0) is generally located 1 cm from the source center and at a polar angle of 90°, i.e., r0 = 1 cm and θ0 = 90°.

[0077] The dose rate constant Λ is characterized by the ratio of the water absorbed dose to the air kerma intensity at the reference point, as shown in Equation (1).

[0078]

[0079] In the formula:

[0080] —Water absorption dose at a radial distance of 1 cm from the source center;

[0081] S K —Air kerma intensity at a radial distance of 1m from the source center.

[0082] The geometric functions based on line sources can be calculated using interpolation methods with discrete point data. The highly simplified approximation provides sufficient accuracy for treatment planning. The geometric functions based on line sources are shown in Equations (2) and (3). When the radioactive distribution is in a cylindrical or annular space, the length L of the cylinder is taken as the effective length, i.e., L = 3 mm is taken in this calculation.

[0083]

[0084] G L (r,θ)=(r 2 -L 2 / 4) -1 (θ=0°) (3)

[0085] Radial dose function g L (r) Considering the absorption and scattering of rays by the medium and the absorption of photons by the outer shell of the particle source, its calculation is shown in formula (4).

[0086]

[0087] One-dimensional anisotropic function φ an (r) represents the ratio of the integral average value of the absorbed dose within a range of 4π to the absorbed dose at the position θ0=90° when the distance r remains constant, as expressed by formula (5).

[0088]

[0089] The two-dimensional anisotropy function F(r,θ) represents the effect of the particle source's shell thickness and the surrounding medium (tissue or water) on photon absorption and scattering on the dose when r is the same but angles are different. The physical meaning is that, with the dose at the perpendicular bisector of the particle source as a reference, the dose at the reference point (r,θ=90°) is the ratio of the dose at the particle source deviating from the perpendicular bisector to the dose at the reference point. Its calculation is shown in formula (6).

[0090]

[0091] Except for the geometric function, which is calculated, all other parameters require accurate dose rate values ​​from the particle source. The measurement distance and measurement angle have a significant impact on the dose distribution of the particle source. To obtain a complete dose distribution database of the particle source, this support uses a movable passive dosimeter support to achieve continuous adjustment of the measurement distance and a rotating bottom dial to achieve continuous adjustment of the angle. The database obtained by this set of measurement supports 30 can cover the absorbed dose values ​​of the particle source at distances of 0-10cm and angles of 0-360°.

[0092] The one-dimensional anisotropic function φ can be obtained by measuring the particle source horizontally. an(r) and the two-dimensional anisotropic function F(r,θ), the radial dose function g can be obtained by placing the particle source vertically. L (r), and during particle implantation therapy, it is necessary to pay attention to the dose distribution of the particle source. The particle source is placed horizontally for measurement, which can obtain the relative dose distribution of the particle source. A large amount of measurement data can be used to draw a contour map of the relative dose, which helps users evaluate the placement of the particle source.

[0093] This application also provides a method for measuring particle source dose distribution, applicable to the measuring device of any of the above embodiments, see [link to relevant documentation]. Figure 7 As shown, it includes the following steps:

[0094] S1: Place the particle source on the mounting bracket along the first direction;

[0095] S2: Each passive dosimeter is mounted on a plurality of measuring brackets, the plurality of measuring brackets 30 being arranged in a circumferential direction around the center of the mounting bracket;

[0096] S3: Control the mounting bracket to rotate relative to the chassis, and measure the particle source within a preset time;

[0097] S4: Change the distance between each of the measuring brackets and the mounting bracket, and measure the particle source within a preset time.

[0098] The following is a detailed description of each step.

[0099] S1: Place the particle source on the mounting bracket along the first direction.

[0100] The specific structure of the mounting bracket 20 is not limited here. For example, in one embodiment, please refer to [reference needed]. Figure 4 The mounting bracket 20 includes a first bracket 21 and a first mounting part 20a, which is a plug hole 21a formed on the top of the first bracket 21 and extending along the length direction of the first bracket 21. The plug hole 21a is used to insert the particle source into the plug hole 21a along the length direction, that is, the particle source can be placed on the first mounting part 20a in the vertical direction.

[0101] By placing the particle source vertically on the first mounting portion 20a of the first support 21, the radial dose distribution of the particle source can be measured.

[0102] Specifically, the insertion hole 21a can be located at the center of the first support 21. The particle source is first placed in the polyimide thin tube (wall thickness 0.03mm, inner diameter 0.8mm), and then the polyimide tube is inserted into the insertion hole 21a.

[0103] In other embodiments, please refer to Figure 5The mounting bracket 20 includes a second bracket 22 with a first mounting part 20a, and the particle source is placed horizontally on the first mounting part 20a.

[0104] Specifically, the first mounting part 20a consists of a mounting post 221, a hanging lug 222, and a tension rope mounted on the second bracket 22. The particle source is placed horizontally on the mounting post 221, and the tension rope and the hanging lug 222 cooperate to fix the particle source. The particle source is first placed in a polyimide tube, which is then placed horizontally on the mounting post 221. The tension rope and the hanging lug 222 cooperate to fix the polyimide tube, thereby fixing the particle source.

[0105] By placing the particle source horizontally on the first mounting part 20a of the second support 22, the two-dimensional dose distribution of the particle source can be measured.

[0106] S2: Each passive dosimeter is mounted on a plurality of measuring supports, and the plurality of measuring supports are arranged in a circumferential direction around the center of the mounting supports.

[0107] Each measuring bracket 30 is arranged in a circumferential direction around the center of the mounting bracket 20, that is, each measuring bracket 30 is located on the circumference of the same circle with the center of the mounting bracket 20 as the center.

[0108] The repeatability of each passive dosimeter is within ±5%.

[0109] In one specific embodiment, please refer to Figure 1 and Figure 2 There are 8 measuring brackets 30, which are arranged in a circumferential direction around the center of the mounting bracket 20, and the central angle between any two adjacent measuring brackets 30 is 45°.

[0110] Each passive dosimeter is placed into a specially made transparent mounting box, and the entire mounting box is installed onto the eight measuring brackets 30. The particle source is placed in the polyimide tube and then inserted into the mounting bracket 20.

[0111] S3: Control the mounting bracket to rotate relative to the chassis, and measure the particle source within a preset time.

[0112] In one embodiment, the preset time is 1.5h-2.5h, that is, the preset time for measuring the particle source dose distribution is 1.5h-2.5h, for example, 1.5h, 2.0h or 2.5h.

[0113] The mounting bracket 20 is rotatable relative to the chassis 10. Exemplarily, in one embodiment, the chassis 10 may be stationary during measurement, while the mounting bracket 20 may be rotatable. Thus, by rotating the mounting bracket 20, the particle source can be rotated relative to the chassis 10, thereby obtaining a dose distribution within the 0°-360° range of the particle source.

[0114] In other embodiments, during the measurement process, the chassis 10 may be rotatable, while the mounting bracket 20 may be non-rotatable. Thus, by rotating the chassis 10, the particle source can be rotated relative to the chassis 10, thereby obtaining the dose distribution of the particle source within the range of 0°-360°. Rotating the chassis 10 does not change the position of the particle source, further improving the accuracy of the measured particle source dose distribution.

[0115] In some other embodiments, during the measurement process, the chassis 10 can be rotatable, and the mounting bracket 20 can also be rotatable. In this way, by rotating the chassis 10, or rotating the mounting bracket 20, or rotating the mounting bracket 20 and the chassis 10 at the same time, the particle source can be rotated relative to the chassis 10, thereby obtaining the dose distribution of the particle source within the range of 0°-360°.

[0116] It should be noted that the specific structure of the mounting bracket 20 rotating relative to the chassis 10 is not limited. For example, the chassis 10 has a through hole 10c at its center, the mounting bracket 20 passes through the through hole 10c, and the particle source is placed in the first mounting part 20a. In this way, the mounting bracket 20 can rotate relative to the chassis 10, so that the particle source can rotate relative to the chassis 10.

[0117] A motor can be connected to the bottom of the mounting bracket 20 or the chassis 10 to achieve uniform rotation of the mounting bracket 20 or the chassis 10. Of course, the mounting bracket 20 or the chassis 10 can also be rotated manually.

[0118] S4: Change the distance between each of the measuring brackets and the mounting bracket, and measure the particle source within a preset time.

[0119] The distance between each measuring bracket 30 and the mounting bracket 20 is changed, and the particle source is measured within a preset time. That is, after a certain distance measurement is completed, the distance between the measuring bracket 30 and the mounting bracket 20 is changed, thereby changing the measurement distance between the passive dosimeter and the particle source. The above steps are repeated to obtain the radial dose distribution of the continuous radial measurement distance.

[0120] In one embodiment, each measuring bracket 30 is slidably mounted on the chassis 10, meaning the measuring bracket 30 and the chassis 10 are in sliding engagement. During the measurement process, the measuring bracket 30 can slide on the chassis 10 to adjust the distance between each measuring bracket 30 and the mounting bracket 20, that is, to adjust the distance between the passive dosimeter and the particle source. In this way, the measurement distance can be continuously adjusted, and the radial dose distribution of the particle source can be measured.

[0121] The specific manner in which each measuring bracket 30 slides into the chassis 10 is not limited here. For example, in one embodiment, please refer to... Figure 1 and Figure 2 The chassis 10 is provided with multiple sliding grooves 10a corresponding to multiple measuring brackets 30. Each sliding groove 10a extends radially along the chassis 10. The multiple measuring brackets 30 are slidably disposed in the corresponding multiple sliding grooves 10a. That is, by providing sliding grooves 10a corresponding to each measuring bracket 30 on the chassis 10, each measuring bracket 30 is disposed in the sliding groove 10a and slides in cooperation with the chassis 10.

[0122] Each slide groove 10a extends radially along the chassis 10, that is, each slide groove 10a is arranged radially on the chassis 10, and each measuring bracket 30 can slide radially along the chassis 10 to move away from or close to the mounting bracket 20.

[0123] In other embodiments, the chassis 10 is provided with a plurality of limiting ribs corresponding to a plurality of measuring brackets 30. Each limiting rib extends radially along the chassis 10. Each measuring bracket 30 is provided with a groove corresponding to the limiting rib. The limiting rib and the groove cooperate to allow each measuring bracket 30 to be slidably disposed in the corresponding slide groove 10a.

[0124] In one embodiment, please refer to Figure 1 and Figure 2 The sidewall of the slide groove 10a is recessed to form a limiting groove 10b, which extends along the extension direction of the slide groove 10a. Each measuring bracket 30 includes a rod portion 30b and a limiting portion 30c connected to the rod portion 30b. The second mounting portion 30a is disposed on the rod portion 30b, and the limiting portion 30c is located in the limiting groove 10b to limit the measuring bracket 30. That is, by setting the limiting groove 10b, and by setting the limiting portion 30c, when the measuring bracket 30 is disposed on the chassis 10, the limiting portion 30c is located in the limiting groove 10b to limit the measuring bracket 30, thereby preventing the measuring bracket 30 from falling out of the slide groove 10a and improving the structural reliability of the measuring device 100.

[0125] For example, the measuring bracket 30 is provided with mounting holes, and the measuring device 100 includes a mounting box. The size of the mounting box can be designed according to the size of the passive dosimeter. The passive dosimeter is placed in the mounting box, and the mounting box is placed at the mounting hole of the measuring bracket 30 to complete the assembly of the passive dosimeter.

[0126] The specific location of the limiting groove 10b is not limited here. For example, the limiting groove 10b can be formed at the bottom of the slide groove 10a or in the middle of the slide groove 10a, as long as it can restrict the measuring bracket 30 from coming out of the slide groove 10a. It should be noted that the restriction of the measuring bracket 30 from coming out of the slide groove 10a refers to coming out in a direction perpendicular to the plane of the chassis 10, and does not restrict the measuring bracket 30 from moving radially along the chassis 10 or coming out of the slide groove 10a radially along the chassis 10.

[0127] In one embodiment, please refer to Figure 1 and Figure 2 Each groove 10a penetrates the outer side wall of the chassis 10, that is, the groove 10a is formed on the outer side wall of the chassis 10 and extends radially along the chassis 10. In this way, each measuring bracket 30 can be inserted into the groove 10a from the outside of the chassis 10, which is beneficial to the assembly of the measuring bracket 30.

[0128] Of course, each groove 10a may also be a blind end that does not penetrate the outer wall of the chassis 10, that is, the outer side of the groove 10a along the radial direction of the chassis 10 is a blind end.

[0129] In one embodiment, each measuring bracket 30 can move within a range of 1cm to 10cm from the mounting bracket 20. The distance between each measuring bracket 30 and the mounting bracket 20 is, for example, 1cm, 1.5cm, 2cm, 3cm, 4cm, 5cm, 6cm, 6.5cm, 7cm, 8cm, 9cm, or 10cm.

[0130] In other words, the distance between the passive dosimeter and the particle source can be adjusted from 1cm to 10cm, thus enabling continuous adjustment of the measurement distance and measurement of the radial dose distribution of the particle source.

[0131] S5: Place the particle source on the mounting bracket along the second direction, wherein the first direction is perpendicular to the second direction;

[0132] Control the relative rotation of the mounting bracket 20 and the chassis 10 to measure the particle source within a preset time;

[0133] The distance between each measuring bracket 30 and the mounting bracket 20 is changed to measure the particle source within a preset time.

[0134] In other words, after the particle source is placed on the mounting bracket 20 along the first direction for measurement, the particle source is then placed on the mounting bracket 20 along the second direction, and the above steps are repeated for measurement to obtain the two-dimensional dose distribution of the particle source.

[0135] It should be noted that the first and second directions can be vertical or horizontal. That is, the particle source can be placed vertically on the mounting bracket 20 for measurement first, and then placed horizontally on the mounting bracket 20 for measurement. Alternatively, the particle source can be placed horizontally on the mounting bracket 20 for measurement first, and then placed vertically on the mounting bracket 20 for measurement. This allows for comprehensive measurement of the particle source dose distribution data using a passive dosimeter, obtaining dose distribution data at any angle from 1-10 cm away from the particle source.

[0136] In the description of this application, the references to terms such as "in one embodiment," "in some embodiments," "in other embodiments," "in yet another embodiment," or "exemplary," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments of this application. In this application, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine the different embodiments or examples described in this application, as well as the features of the different embodiments or examples.

[0137] The above description is merely a preferred embodiment of this application and is not intended to limit the application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application are included within the scope of protection of this application.

Claims

1. A device for measuring particle source dose distribution, characterized in that, include: Chassis; The mounting bracket is provided with a first mounting part, which is used to mount a particle source. The particle source is pre-placed in a polyimide thin tube; the mounting bracket is rotatably configured relative to the chassis; Multiple measuring brackets are mounted on the chassis, with each bracket spaced apart around the periphery of the mounting bracket and capable of moving radially along the chassis to move away from or closer to the mounting bracket. Each measuring bracket has a second mounting portion for mounting a passive dosimeter. Each measuring bracket is slidably mounted on the chassis. The chassis has multiple sliding grooves corresponding to the multiple measuring brackets, each groove extending radially along the chassis. The multiple measuring brackets are slidably mounted in the corresponding multiple sliding grooves. The sidewalls of the sliding grooves are recessed to form limiting grooves. Each measuring bracket includes a rod and a limiting portion connected to the rod. The second mounting portion is mounted on the rod, and the limiting portion is located in the limiting groove to limit the position of the measuring bracket. The mounting box is sized to match the passive dosimeter and is used to house the passive dosimeter; the second mounting part has a mounting hole and the mounting box is placed in the mounting hole. The positions of the first mounting part and the second mounting part satisfy the following condition: when the particle source is mounted on the first mounting part and the passive dosimeter is mounted on the second mounting part, the passive dosimeter is aligned with the center of the particle source.

2. The measuring device according to claim 1, characterized in that, Each of the aforementioned grooves penetrates the outer side wall of the chassis.

3. The measuring device according to claim 1, characterized in that, Each of the measuring brackets is arranged circumferentially around the center of the mounting bracket.

4. The measuring device according to claim 1, characterized in that, The chassis has a through hole at its center, and the mounting bracket passes through the through hole.

5. The measuring device according to any one of claims 1, characterized in that, The mounting bracket includes a first bracket, and the first mounting portion is a plug hole formed on the top of the first bracket and extending along the length direction of the first bracket, for inserting the particle source into the plug hole along the length direction.

6. The measuring device according to any one of claims 1, characterized in that, The mounting bracket includes a second bracket with the first mounting part, and the particle source is placed horizontally on the first mounting part.

7. The measuring device according to claim 6, characterized in that, The first mounting part consists of a mounting post, a hanging lug, and an elastic cord mounted on the second bracket. The particle source is placed horizontally on the mounting post, and the elastic cord and the hanging lug cooperate to fix the particle source.

8. The measuring device according to any one of claims 1, characterized in that, Each of the aforementioned measuring brackets can move within a range of at least 1cm-10cm from the mounting bracket.

9. A method for measuring particle source dose distribution, applied to the measuring device according to any one of claims 1-8, characterized in that, The measurement method includes: Place the particle source on the mounting bracket along the first direction; Each passive dosimeter is mounted on a plurality of measuring brackets, which are arranged in a circumferential direction around the center of the mounting brackets; The mounting bracket is controlled to rotate relative to the chassis, and the particle source is measured within a preset time. The distance between each of the measuring brackets and the mounting bracket is changed, and the particle source is measured within a preset time.

10. The measurement method according to claim 9, characterized in that, After the step of changing the distance between each of the measuring brackets and the mounting bracket, and measuring the particle source within a preset time, the method further includes: The particle source is placed on the mounting bracket along the second direction, wherein the first direction is perpendicular to the second direction; The mounting bracket is controlled to rotate relative to the chassis, and the particle source is measured within a preset time. The distance between each of the measuring brackets and the mounting bracket is changed, and the particle source is measured within a preset time.

11. The measurement method according to claim 9, characterized in that, The preset time is 1.5h-2.5h.

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