Neutron capture therapy shielding device and method for manufacturing the same based on 3D printing technology

Abstract

The present invention relates to the field of radiation protection technology and discloses a neutron capture therapy shielding device based on 3D printing technology, including a 3D model of body surface skin, a 3D model of a tumor, and a pre-molded composite mold, as well as a method for manufacturing the same. The pre-molded composite mold is obtained by casting a basic composite mold, which is provided with a hollow section and an injection port structure, and the basic composite mold includes a navigation guide plate for neutron irradiation planning, a skin contact device, a connecting device, and a radiation source receiving device, to which a neutron radiation source is connected on one side of the radiation source receiving device, and the other side is connected to the connecting device. The skin contact device is incorporated into the connecting device, and the skin contact device is sequentially connected to the navigation guide plate for neutron irradiation planning and the 3D model of a tumor, for the purpose of close contact with the 3D model of body surface skin. According to the present invention, an individualized shielding protection device can be designed according to the actual situation of radiation therapy for a patient's tumor, and the design is simple.

Description

Technical Field

[0001] The present invention relates to the field of radiation protection technology, and more specifically, to a neutron capture therapy shielding device based on 3D printing technology and a manufacturing method thereof.

Background Art

[0002] Neutron capture therapy (NCT) is a type of two-element combined chemical and radiation cancer treatment method. It is a treatment method that uses secondary charged particles generated by the capture reaction of a non-radioactive element (such as 10 B or Gd) with neutrons to destroy cancer cells. Although the neutrons used in neutron capture therapy have a short range, their flight paths are complex and prone to change. The secondary particles generated thereby may also interact with surrounding normal tissues, potentially causing health hazards to the human body and environmental radiation pollution. Therefore, the realization of effective shielding and protection against neutrons and γ-rays is one of the important elements in the new generation of neutron capture therapy.

[0003] As a conventional neutron shielding material, boron carbide (B4C) is known as a material with excellent shielding performance. 10 The absorption cross-section of B for thermal neutrons is reported to be 3,837 barns. Boron steel, lead plates, and large concrete structures mainly composed of boron have been used as the main materials for nuclear protection. In addition, boron-containing polyethylene plates are currently common neutron shielding materials, and the 10 B contained in boron carbide (B4C) can efficiently absorb low-energy neutrons. However, commercially available boron polyethylene materials are manufactured by mass production processes and are not suitable for the secondary forming process of complex structural parts in the actual use process. It is difficult to achieve individualized shielding in a complex environment, and there are still problems with the practical effect.

[0004] Therefore, overcoming the application limitations of conventional neutron shielding materials and realizing more individualized shielding protection is an urgent issue that engineers in this field must address. [Overview of the project]

[0005] To solve the above problems, the present invention provides a neutron capture therapy shielding device and a method for manufacturing the same based on 3D printing technology.

[0006] To achieve the above objectives, the present invention employs the following technical solutions.

[0007] A neutron capture therapy shielding device based on 3D printing technology, comprising a 3D model of body surface skin, a 3D model of a tumor, and a pre-formed composite mold.

[0008] The pre-molded composite mold is obtained by applying a casting process to a basic composite mold, and the basic composite mold is provided with a hollow section and an injection port structure.

[0009] The basic composite mold includes a navigation guide plate for neutron irradiation planning, a skin contact device, a connection device, and a radiation source receiver. A neutron radiation source is connected to one side of the radiation source receiver, and the other side is connected to the connection device. The skin contact device is incorporated into the connection device, and the skin contact device is sequentially connected to the navigation guide plate for neutron irradiation planning and the tumor 3D model, with the aim of achieving close contact with the body surface skin 3D model.

[0010] Preferably, the skin contact device is designed based on a navigation guide plate for neutron irradiation planning, and the 3D model of the body surface skin, the 3D model of the tumor, and the navigation guide plate for neutron irradiation planning are designed as a set, and are designed based on the neutron radiation source and the 3D model of the tumor.

[0011] Preferably, the casting process uses a solution of silicone rubber and silicone curing agent mixed with boron carbide, and the mixed solution is prepared by uniformly stirring and mixing the boron carbide, silicone rubber, and silicone curing agent in a ratio of boron carbide:silicone rubber:silicone curing agent = 0.1:1:0.1. After that, heating and drying is performed at 60°C for 12 to 20 hours.

[0012] Preferably, the skin contact device, connection device, and radiation source receiving device are designed as adjustable and replaceable modular devices.

[0013] Preferably, a lead shielding shell is provided on the outside of the basic composite mold.

[0014] Preferably, the basic composite mold is manufactured by 3D printing, the printing material is QSY white resin (high-density polyethylene resin), the printing accuracy is ±0.15 / 100mm, and the minimum wall thickness requirement is 0.3mm.

[0015] A method for manufacturing a neutron capture therapy shielding device based on 3D printing technology, comprising the following steps:

[0016] Based on the patient's image data, 3D reconstruction of the patient's tumor and skin surface is performed.

[0017] Based on the irradiation area centered on the patient's tumor, a navigation guide plate for neutron irradiation planning will be designed.

[0018] A skin-contact device will be designed based on a navigation guide plate for neutron irradiation planning.

[0019] Based on the neutron radiation source and tumor 3D model, the connection device and radiation source receiver device are designed, and the basic composite mold is constructed.

[0020] A basic composite mold is designed with a hollow section and injection port, and then 3D printed.

[0021] Prepare a solution by mixing boron carbide with silicone rubber and a silicone curing agent, and perform casting and drying molding on a basic composite mold to obtain a molded composite mold.

[0022] A neutron capture therapy shielding device is configured by combining a body surface skin 3D model, a tumor 3D model, and a molded composite mold.

[0023] By the above technical solution, the present invention discloses a neutron capture therapy shielding device based on 3D printing technology and its manufacturing method, and compared with the prior art, it has the following advantageous effects.

[0024] The present invention overcomes the application limitations in conventional neutron shielding materials. By applying 3D printing technology to the field of neutron radiation protection, it breaks through the limitations of conventional boron-containing polyethylene shielding materials and enables the design of an individualized shielding device that conforms to the actual situation in the treatment of patients' tumors (radiation therapy).

[0025] The neutron capture therapy shielding device based on the present invention is easy to be individually designed according to the shape of the patient's tumor, has many components, and can be flexibly assembled. Therefore, it can support the user's independent design and production, and enable the integration of individualization and mass production. Therefore, it also has broad application possibilities in terms of practicality and economy.

[0026] To more clearly explain the technical solution of the present invention or the prior art, the following will be described with reference to the drawings in a clear and easy-to-understand manner. Obviously, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative efforts.

Brief Description of the Drawings

[0027] [Figure 1(a)] It is a schematic configuration diagram of a navigation guide plate for a neutron irradiation plan when the neutron capture therapy shielding device is in close contact with the irradiation site of a patient. [Figure 1(b)]It is a schematic configuration diagram of a tumor 3D model when a neutron capture therapy shielding device adheres to the irradiation site of a patient. [Figure 2] It is a schematic configuration diagram of the structure of a neutron capture therapy shielding device. [Figure 3] It is a schematic configuration diagram of a radiation source receiving device. [Figure 4] It is a schematic configuration diagram of a connecting device. [Figure 5] It is a schematic configuration diagram of a skin adhesion device. [Figure 6] It is a schematic configuration diagram of a navigation guide plate for neutron irradiation planning. [Figure 7] It is a schematic configuration diagram of a tumor 3D model. [Figure 8] It is a schematic configuration diagram of a body surface skin 3D model. [Figure 9(a)] It is a schematic diagram of the DICOM image data of a patient. [Figure 9(b)] It is a schematic diagram of a multi-modal display of the state of a tumor target area of a patient. [Figure 9(c)] It is a schematic diagram showing the 3D reconstruction of the skin tissue and tumor tissue of a patient. [Figure 10(a)] It is a schematic diagram for designing a guide plate based on skin and tumor tissues. [Figure 10(b)] It is a schematic configuration diagram showing a navigation guide plate for neutron irradiation planning after design completion. [Figure 11(a)] It is a front view of a CAD black-and-white line drawing of the neutron capture therapy shielding device shown in FIG. 2. [Figure 11(b)] It is a perspective view of a CAD black-and-white line drawing of the neutron capture therapy shielding device shown in FIG. 2. [Figure 11(c)] It is a perspective view of a CAD black-and-white line drawing of the neutron capture therapy shielding device shown in FIG. 2 from another angle. [Figure 11(d)] It is a plan view of a CAD black-and-white line drawing of the neutron capture therapy shielding device shown in FIG. 2.

Embodiments for Carrying Out the Invention

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the drawings. Clearly, the embodiments described are only some, and not all, embodiments of the present invention. All other embodiments that can be obtained by those skilled in the art without creative effort based on the embodiments of the present invention are all within the scope of the protection of the present invention.

[0029] 3D printing technology is one of the leading advanced manufacturing technologies of the modern era and is widely applied in diverse fields such as aerospace, defense and military, jewelry, and biomedicine. By using medical 3D reconstruction technology to create individualized models from patient image data, it becomes possible to design and manufacture pre-operative individualized models, surgical guide plates, rehabilitation support devices, and more.

[0030] An embodiment of the present invention, a neutron capture therapy shielding device based on 3D printing technology, includes a 3D model of body surface skin, a 3D model of a tumor, and a pre-molded composite mold. The pre-molded composite mold is obtained by casting a basic composite mold; please refer to the schematic diagrams of the CAD black and white line drawings of the neutron capture therapy shielding device in Figure 2 and Figures 11(a) to 11(d).

[0031] As shown in Figure 2, the basic composite mold includes a neutron irradiation planning navigation guide plate 2, a skin contact device 3, a connection device 4, and a radiation source receiver 5. A neutron radiation source is connected to one side of the radiation source receiver 5, and the other side is connected to the connection device 4. The skin contact device 3 is incorporated into the connection device 4, and the skin contact device 3 is sequentially connected to the neutron irradiation planning navigation guide plate 2 and the tumor 3D model 1, with the aim of achieving close contact with the body surface skin 3D model.

[0032] Here, the skin contact device 3 is manufactured by cutting and designing based on the neutron irradiation planning navigation guide plate 2, which has been positioned and designed using the tumor 3D model 1. The body surface skin 3D model, tumor 3D model 1, and neutron irradiation planning navigation guide plate 2 are designed as a set based on a Sketch sketch and are designed according to the specifications of the neutron radiation source device and the tumor 3D model 1.

[0033] The skin contact device 3, connection device 4, and radiation source receiving device 5 are designed as adjustable and replaceable modular devices. The connection device 4 can be configured in multiple dimensions, such as 10cm x 5cm, 10cm x 10cm, 15cm x 10cm, 20cm x 15cm, and 30cm x 20cm. The diameter of the radiation source receiving device 5 is determined by the device specifications and is usually achievable with a single diameter design.

[0034] In the implementation process, the height of the skin contact device 3 is 15 cm, the connection device 4 is designed to have a wall thickness of 1 cm and a height of 15 cm according to the model, and the diameter of the radiation source receiving device 5 is determined according to the model, with a wall thickness of 1 cm and a height of 15 cm.

[0035] The aforementioned basic composite mold is manufactured by 3D printing, using QSY white resin (high-density polyethylene resin) as the printing material, with a printing accuracy of ±0.15 / 100mm and a minimum wall thickness requirement of 0.3mm.

[0036] Furthermore, in the implementation process, secondary gamma rays generated by the reaction between neutrons and boron carbide are taken into consideration, and a lead shielding shell is provided on the outside of the basic composite mold. The thickness of this lead shielding shell can be set within the range of 5 to 20 mm.

[0037] A hollow section and injection port structure are designed into the obtained basic composite mold, and casting is performed using a solution of silicone rubber and silicone curing agent mixed with boron carbide. The mixed solution is prepared by uniformly stirring and mixing boron carbide:silicone rubber:silicone curing agent in a ratio of 0.1:1:0.1. After that, it is heated and dried at 60°C for a heating and drying time of 12 to 20 hours.

[0038] Furthermore, as another embodiment of the present invention, a method for manufacturing a neutron capture therapy shielding device based on 3D printing technology, comprising the following steps, is also provided.

[0039] 3D reconstruction of the patient's tumor and skin: Figure 9(a) shows the patient's DICOM image data, and Figure 9(b) shows a multimodal display of the state of the patient's tumor target region. Using the mainstream medical 3D reconstruction software "Mimics," appropriate thresholds for the tumor and skin were set using the thresholding tool "Thresholding" based on the patient's DICOM image data, appropriate regions of interest were separated using the mask splitting tool "Split Mask," further modifications and optimizations were made using tools such as "Edit Mask," and finally "Calculate 3D from Mask" was executed to perform 3D reconstruction of the tumor and skin (see Figure 9(c)).

[0040] Design of Navigation Guide Plate 2 for Neutron Irradiation Planning: Refer to Figures 10(a) and 10(b). (1) Design and generation of the guide plate base: Use the lasso selection tool "Lasso Area Mark" to specify the irradiation area centered on the tumor. The area conforms to the design standards for radiation therapy planning and optimizes radiation shielding. Use the tool "Copy to Part" to isolate the selected area and create an editable base plate. (2) Optimization of the navigation guide plate base design: Under the tool "Design", use "Offset" and "Uniform Offset" to offset by 5 mm and create a closed three-dimensional shape. Further refine and optimize the design using commands such as "Trim", "Fix", and "Fill Hole Free" to obtain the completed model of Navigation Guide Plate 2 for Neutron Irradiation Planning.

[0041] Design of Skin-to-Skin Contact Device 3: (1) Individualized Skin-to-Skin Contact Design: I. Sketch Design and Optimization of Irradiation Angle (Vertical Direction): Create a new sketch using the "Sketch" tool, place a mask at the planned irradiation angle (vertical direction), and construct the sketch. Align the sketch with the coordinate system of the neutron irradiation planning navigation guide plate 2, adjust the relative position of the guide plate 2 and the sketch using the "Align" tool, and separate the sketch from the guide plate to allow for vertical extension. Determine the sketch size considering the size ratio with the neutron irradiation planning navigation guide plate 2. II. Individualized Design Based on the Contour of the Neutron Irradiation Planning Navigation Guide Plate 2: On the sketch screen, select "Import References to Sketch" and import the contour line of the neutron irradiation planning navigation guide plate 2 via "outline". Create an individualized sketch based on the contour line and materialize and display it. (2) Design of Skin-to-Skin Contact Device 3 Based on the Inner Contour Line: Based on the contour line of the neutron irradiation planning navigation guide plate 2 planned in the sketch, place a rectangle with dimensions that allow for effective irradiation of the tumor and design the skin-to-skin contact device 3. Based on the internal and external contour lines, a three-dimensional model is formed by extending it 150 mm upward in the direction of irradiation using "Design-Extrude". The thoracic cage model is displayed, the cylindrical model is superimposed on the thoracic cage model, and the cylindrical model is removed from the patient's contour line using Boolean operations with the "Design-Subtraction" tool, completing the first part of the individualized irradiation device based on the contour lines of the patient's skin and the radiation therapy planning guide plate.

[0042] Design of connector 4: Design a reusable connector 4 with multiple sizes depending on the tumor condition and the diameter of the radiation equipment. Connect it to the skin contact device 3 using a push-pull method, ensuring a tight fit based on the sketch design and preventing radiation leakage. Based on the outer contour of the skin contact device 3, expand it 5 mm outward using "Sketch-Tools-Offset," and then perform "Design-Extrude" on the newly obtained contour and the original outer contour, respectively. Extrude the original outer contour by 180 mm and the newly obtained contour by 150 mm, and then use a Boolean operation with "Design-Subtraction" to obtain the intermediate connector 4.

[0043] Design of the radiation source receiving device 5: Depending on the radiation source (type of irradiation equipment), a receiving device with the same diameter as the radiation source, with the center as a circle, is designed in a Sketch sketch and extruded to a height of 150 mm using "Design-Extrude". An inner cylinder is formed by offsetting it inward by 5 mm using "Sketch-Tools-Offset", and the inner cylinder is moved to half the size of the outer cylinder using "Align" and positioned, and the inner and outer cylinders and connecting device 4 are sheared using a Boolean operation with "Design-Subtraction" to complete the receiving device.

[0044] Basic composite mold hollow section and injection port design: Using Hollow software, the basic composite mold obtained above is given a hollow section to allow injection, and injection ports are provided in appropriate positions. The diameter of the injection port is made slightly smaller than the wall thickness to prevent penetration, and multiple ports are provided to enable rapid injection.

[0045] 3D Printing: The pre-designed basic composite mold is output in "STL" format, and pre-processing such as modification and support generation is performed using 3D printer slicer software. The mold is then printed using QSY white resin (high-density polyethylene resin) with a light-curing printer, followed by support removal, cleaning, polishing, and UV curing. The quality of the 3D printed model, including the hollow parts of the mold and the flow of the injection port, is inspected.

[0046] A solution is prepared by mixing silicone rubber and a silicone curing agent with boron carbide, and this solution is cast and dried into a basic composite mold to obtain a pre-molded composite mold. This completes the 3D model of the body surface skin, the 3D model of the tumor, and the pre-molded composite mold that constitute the neutron capture therapy shielding device.

[0047] Considering the secondary gamma rays generated by the reaction between neutrons and boron carbide, a lead shielding shell with a thickness of 5 to 20 mm is provided on the outside of the main unit. The lead shielding shell is molded and fixed to match the shape of the radiation source receiving device 5 and the connecting device 4 in the main unit, ensuring shielding against impurity radiation and gamma rays.

[0048] The apparatus and manufacturing method described above according to the present invention can be applied not only to neutron capture therapy but also to other radiation therapies and shielding designs.

[0049] The examples described herein are described step-by-step, with each example emphasizing its unique aspects. Common or similar parts between examples are cross-referenced.

[0050] Based on the above description of the published examples, those skilled in the art will be able to implement or utilize the present invention. Various modifications to these examples will be obvious to those skilled in the art, and the general principles defined herein are applicable to other examples without departing from the spirit or scope of the invention. Accordingly, the present invention is not limited to the examples shown herein, but applies to the maximum extent consistent with the principles and novelty disclosed herein. [Explanation of symbols]

[0051] 1. Tumor 3D Model 2. Navigation guide plate for neutron irradiation planning 3. Skin contact device 4. Connection device 5. Radiation source receiving device.

Claims

1. A neutron capture therapy shielding device based on 3D printing technology, including a 3D model of the body surface skin, a 3D model of a tumor, and a pre-formed composite mold, The aforementioned pre-molded composite mold is obtained by performing a casting process on a basic composite mold, and the basic composite mold is provided with a hollow section and an injection port structure. The basic composite mold includes a navigation guide plate for neutron irradiation planning, a skin contact device, a connection device, and a radiation source receiver, wherein a neutron radiation source is connected to one side of the radiation source receiver, and the other side is connected to the connection device, the connection device incorporates a skin contact device, and the skin contact device is sequentially connected to the navigation guide plate for neutron irradiation planning and a tumor 3D model, and is characterized by its purpose of close contact with a body surface skin 3D model, thus providing a neutron capture therapy shielding device based on 3D printing technology.

2. The neutron capture therapy shielding device based on 3D printing technology according to claim 1, characterized in that the skin contact device is designed based on the neutron irradiation planning navigation guide plate, the body surface skin 3D model, tumor 3D model, and neutron irradiation planning navigation guide plate are designed as a set, and the device is designed based on the neutron radiation source and tumor 3D model.

3. The neutron capture therapy shielding device based on 3D printing technology according to claim 1, characterized in that the casting process uses a mixed solution of silicone rubber and silicone curing agent mixed with boron carbide, the mixed solution is prepared by uniformly stirring and mixing boron carbide:silicone rubber:silicone curing agent in a ratio of boron carbide:silicone rubber:silicone curing agent = 0.1:1:0.1, and thereafter heat drying is performed at 60°C, the heat drying time being 12 to 20 hours.

4. The neutron capture therapy shielding device based on 3D printing technology according to claim 1, characterized in that the skin contact device, connecting device, and radiation source receiving device are designed as adjustable and replaceable modular devices.

5. A neutron capture therapy shielding device based on 3D printing technology according to claim 1, characterized in that a lead shielding shell is provided on the outside of the basic composite mold.

6. The neutron capture therapy shielding device based on 3D printing technology according to claim 1, characterized in that the basic composite mold is manufactured by 3D printing, the printing material is QSY white resin (high-density polyethylene resin), the printing accuracy is ±0.15 / 100 mm, and the minimum wall thickness requirement is 0.3 mm.

7. A method for manufacturing a neutron capture therapy shielding device based on 3D printing technology, Step (1) to perform 3D reconstruction of the patient's tumor and body surface skin based on the patient's image data, Step (2) involves designing a navigation guide plate for neutron irradiation planning based on the irradiation area centered on the patient's tumor, Step (3) of designing a skin contact device based on a navigation guide plate for neutron irradiation planning, Step (4) involves designing a connection device and a radiation source receiver based on a neutron radiation source and a tumor 3D model, and constructing a basic composite mold. Step (5) involves designing a hollow section and injection port in a basic composite mold and performing 3D printing, Step (6) involves preparing a solution by mixing silicone rubber and a silicone curing agent with boron carbide, and then casting and drying the solution into a basic composite mold to obtain a pre-molded composite mold. Step (7) of constructing a neutron capture therapy shielding device by combining a 3D model of the body surface skin, a 3D model of a tumor, and a pre-formed composite mold, A method for manufacturing a neutron capture therapy shielding device, characterized by including the following:

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