Radiation shielding device and boron neutron capture therapy system

Abstract

The utility model relates to the technical field of medical treatment, in particular to a radiation shielding device and a boron neutron capture therapy system.The radiation shielding device comprises a first shielding layer used for shielding neutron beam scattering and a second shielding layer which has no shielding effect on neutron beams and is used for shielding gamma rays in the neutron beams. The first shielding layer and the second shielding layer are arranged in an attached mode, the first shielding layer is provided with a beam outlet hole allowing a neutron beam to penetrate through, and the position, corresponding to the beam outlet hole, of the second shielding layer is not provided with the beam outlet hole, so that the second shielding layer is kept complete. Wherein the radiation shielding device can effectively protect normal tissues of a patient from being damaged by scattered neutron beams and gamma rays, and the normal tissues are prevented from being damaged by radiation; the method does not need to adapt to body types of patients, is high in universality and does not need to be customized according to body type differences of the patients, cost is remarkably reduced, and economic burdens of the patients are smaller. And direct contact with a patient is not needed, so that the comfort of the patient is better while the shielding effect is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of medical treatment, in particular to a radiation shielding device and a boron neutron capture treatment system. Background Art

[0002] Boron neutron capture therapy (BNCT) has the characteristics of binary targeting. Boron-containing compounds selectively accumulate in the cells of cancer tissues, and then low-energy neutron beams are used to irradiate cancer tissues, triggering the following reactions at the cellular scale: 10 B+n→α+ 7 Li+0.478MeV, thus achieving targeted killing of cancer cells. However, since boron drugs are inevitably distributed in normal tissues, and there is a certain degree of scattering of the neutron beam at the beam exit, it is necessary to evaluate the absorbed dose of normal tissues before BNCT treatment. If the dose exceeds the standard, protection of normal tissues is required.

[0003] The traditional radiation shielding solution is to wear a shielding suit made of wearable flexible material on the patient to cover the non-irradiated parts and protect the normal tissue. However, the disadvantage of this shielding method is that the body shapes of patients vary greatly, and the universality of shielding suits is poor; if customized according to the patient's body shape, it will take a long time and cost a lot; in addition, although the shielding suit is flexible, it is heavy and less comfortable to wear, and the radiation treatment time is long, resulting in poor patient comfort during the treatment process.

[0004] In addition, there is also a radiation shielding solution in the prior art, such as a radiation shielding device based on medical imaging disclosed in a Chinese utility model patent with announcement number CN206535012U. The device collects the patient's body shape data based on medical scans, processes the data and establishes a three-dimensional model, and obtains a customized shielding body through 3D printing. Although the shielding effect of this shielding body is good, the production time of this customized shielding body is poor, the cost is high, and it is not universal. Summary of the invention

[0005] The technical problem to be solved by the utility model is to solve the technical defects in the prior art that the flexible shielding clothing has poor versatility due to the large differences in body shapes of patients, and that the production of customized flexible shielding clothing or 3D printed shielding bodies takes a long time and is costly.

[0006] In order to solve the above technical problems, the technical solution provided by the utility model is as follows: a radiation shielding device, comprising a first shielding layer for shielding neutron beam scattering and a second shielding layer for shielding gamma rays, the first shielding layer and the second shielding layer are arranged in close contact with each other, the first shielding layer is provided with a beam exit hole for accommodating the passage of the neutron beam, and the second shielding layer is not provided with a beam exit hole at a position corresponding to the beam exit hole so as to maintain integrity.

[0007] In a preferred embodiment, the first shielding layer includes but is not limited to a boron-containing polyethylene plate, and the second shielding layer includes but is not limited to a lead plate.

[0008] A preferred embodiment further includes a shielding unit installed separately from the first shielding layer, the material of the shielding unit is the same as that of the first shielding layer, the beam outlet hole is arranged on the shielding unit, and the first shielding layer is provided with a mounting hole adapted to the shielding unit.

[0009] In a preferred embodiment, a positioning mechanism is provided between the first shielding layer and the shielding unit, and the positioning mechanism comprises:

[0010] A positioning protrusion, wherein at least one radially extending positioning protrusion is provided at an edge of an outer wall of the shielding unit close to one end;

[0011] Positioning groove: the first shielding layer is provided with a positioning groove adapted to the positioning protrusion.

[0012] The utility model also provides a boron neutron capture therapy system, which at least includes a beam shaping body, wherein the beam shaping body is provided with a beam outlet, and also includes the radiation shielding device, wherein the radiation shielding device is arranged at the beam outlet of the beam shaping body, the position and size of the beam outlet are adapted to the beam outlet, the first shielding layer is located on a side close to the beam shaping body, and the second shielding layer is located on a side away from the beam shaping body.

[0013] A preferred embodiment further comprises a collimator located in the beam shaping body, wherein the beam output end of the collimator protrudes from the outer wall of the beam shaping body, and the protruding portion is a conical boss, and the beam outlet is located at the beam output end of the collimator.

[0014] In a preferred embodiment, the beam exit hole on the first shielding layer is configured as a tapered hole matched with the tapered boss, and the height of the tapered boss protruding from the outer wall of the beam shaping body is matched with the thickness of the first shielding layer.

[0015] The utility model also provides a boron neutron capture therapy system, which at least includes a beam shaping body, and the beam shaping body is provided with a beam outlet. It is characterized in that it also includes the radiation shielding device, and the radiation shielding device is arranged at the beam outlet of the beam shaping body. The position of the beam outlet is adapted to the beam outlet, the first shielding layer is located on a side close to the beam shaping body, the second shielding layer is located on a side away from the beam shaping body, and the positioning protrusion is located on one side of the second shielding layer.

[0016] In a preferred embodiment, the first shielding layer is arranged in close contact with the outer wall of the beam shaping body.

[0017] In a preferred embodiment, the radiation shielding device and the beam shaping body are detachably matched.

[0018] Compared with the prior art, the radiation shielding device and boron neutron capture therapy system of this embodiment have the following beneficial effects:

[0019] (1) The radiation shielding device is arranged at the beam outlet of the beam shaper, wherein the first shielding layer is used to shield the scattering of the neutron beam, and the second shielding layer is used to shield the gamma rays, thereby effectively protecting the patient's normal tissue from being harmed by the scattered neutron beam and gamma rays and from radiation damage.

[0020] (2) The radiation shielding device is arranged at the beam outlet of the beam shaping body. It does not need to be adapted to the patient's body shape. It has strong versatility and does not need to be customized according to the patient's body shape. The cost is significantly reduced, and the economic burden on the patient is smaller.

[0021] (3) The radiation shielding device does not need to be in direct contact with the patient, which ensures the shielding effect while improving the patient's comfort.

[0022] (4) The first shielding layer is provided with a separately installed shielding unit, and the beam outlet hole is provided on the shielding unit. Thus, the specification of the beam outlet hole can be adjusted by replacing the shielding unit to meet the needs of different diseases. The invention has the technical advantages of simple structure, convenient adjustment and wider application range.

[0023] (5) The radiation shielding device and the beam shaping body can be detachably matched, which facilitates replacement of the radiation shielding device. The appropriate radiation shielding device can be replaced according to the patient's cancer type, lesion location, etc., and has a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a beam shaping body in a boron neutron capture therapy system shown in Example 1;

[0025] Figure 2 This is a schematic diagram of the positional relationship between the radiation shielding device, the beam shaping body and the patient during treatment with the boron neutron capture therapy system shown in Example 1;

[0026] Figure 3 This is a schematic diagram of the structure of the radiation shielding device in the first embodiment in an explosion state;

[0027] Figure 4 It is a schematic diagram of the structure of a beam shaping body and a radiation shielding device in a boron neutron capture therapy system shown in Example 2;

[0028] Figure 5This is a schematic diagram of the positional relationship between the radiation shielding device, the beam shaping body and the patient during treatment by the boron neutron capture therapy system shown in Example 2;

[0029] Figure 6 This is a schematic diagram of the structure of the radiation shielding device in the third embodiment in an explosion state;

[0030] Figure 7 for Figure 6 A schematic cross-sectional view of the radiation shielding device shown;

[0031] Figure 8 is a schematic structural diagram of the first shielding layer in Embodiment 3;

[0032] Fig. 9 It is a schematic diagram of the structure of the shielding unit in the third embodiment. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0034] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, an integral connection, or a detachable connection; it can be the internal connection of two components; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] Embodiment 1

[0037] like Figure 1 As shown, the beam shaping body 10 of the accelerator-based boron neutron capture therapy system includes materials such as magnesium fluoride, lead, and lithium fluoride, which slow down the high-energy neutrons generated by the neutron target into a neutron beam mainly composed of epithermal neutrons suitable for cancer treatment, and the neutron beam is emitted from the beam outlet 11. There is a certain proportion of scattering in the neutron beam passing through the beam shaping body 10, and this part of neutrons will irradiate the patient's healthy tissues and cause radiation damage.

[0038] In order to protect the patient's normal tissue dose from not exceeding the dose limit specified by the American Association of Physicists in Medicine AAPM during treatment with the boron neutron capture therapy system, a radiation shielding device 20 is provided in this embodiment, such as Figure 2 As shown, the radiation shielding device 20 is disposed at the beam outlet 11 of the beam shaping body 10 and is located between the beam shaping body 10 and the patient 30 .

[0039] like Figure 2 , Figure 3 As shown, the radiation shielding device 20 in this embodiment includes a first shielding layer 21 and a second shielding layer 22 that are bonded to each other. Among them, the first shielding layer 21 is used to shield the scattering of the neutron beam. As a preference, in this embodiment, the first shielding layer 21 is a boron-containing polyethylene sheet. Of course, the boron-containing polyethylene sheet is a preferred embodiment of this embodiment, and other existing materials that can shield the scattering of neutron beams can be used, such as a thermal neutron absorbing material containing lithium.

[0040] In order to ensure that the neutron beam can be smoothly irradiated at the lesion position of the patient 30 and shield the neutron beam scattering at the non-lesion position, the first shielding layer 21 is provided with a beam exit hole 23 for accommodating the neutron beam to pass through, and the position and size of the beam exit hole 23 are adapted to the beam outlet 11.

[0041] The function of the second shielding layer 22 is to shield gamma rays. Therefore, the position on the second shielding layer 22 corresponding to the beam exit hole 23 is not provided with a beam exit hole so as to keep it intact. In this embodiment, the second shielding layer 22 is preferably a lead plate. Of course, other existing materials that can shield gamma rays can also be selected. The sources of gamma rays include but are not limited to gamma ray contamination in the neutron beam, secondary gamma rays generated by nuclear reactions between neutrons and beam moderator materials, and secondary gamma rays generated by nuclear reactions between neutrons and the first layer of shielding materials.

[0042] In this embodiment, the first shielding layer 21 is located on a side close to the beam shaping body 10 , and the second shielding layer 22 is located on a side away from the beam shaping body 10 .

[0043] Preferably, in this embodiment, the first shielding layer 21 is arranged in close contact with the outer wall of the beam shaping body 10 , leaving no gap therebetween.

[0044] It should be noted that the radiation shielding device 20 of this embodiment can be fixedly arranged on the outer wall of the beam shaping body 10, but this method makes the function of the boron neutron capture therapy system become single. Preferably, the radiation shielding device 20 and the beam shaping body 10 can be arranged in a detachable matching relationship, so that the radiation shielding device 20 can be easily replaced, and other suitable shielding devices of other material types, thicknesses, etc. can be selected according to the patient's cancer type, lesion location, etc., to broaden its application range.

[0045] It should be emphasized that the detachable matching relationship between the radiation shielding device 20 and the beam shaping body 10 can be achieved by any technical means of the prior art, including but not limited to: a mounting position is set on the outer wall of the beam shaping body, and the radiation shielding device is detachably mounted on the mounting position by bolts or buckles; the radiation shielding device is an independent structure and is placed in a corresponding position when in use. In short, the present application does not impose a sole restriction on the detachable matching relationship between the radiation shielding device 20 and the beam shaping body 10.

[0046] Embodiment 2

[0047] like Figure 4 , Figure 5 As shown, the difference between this embodiment and the first embodiment is that the beam outlet end of the collimator 12 located in the beam shaping body 10 protrudes from the outer wall of the beam shaping body 10, and the protruding part is a conical boss 13, wherein the beam outlet 11 is located at the beam outlet end of the collimator 12.

[0048] Correspondingly, the beam exit hole 23 on the first shielding layer 21 is configured as a tapered hole adapted to the tapered boss 13 .

[0049] Preferably, in this embodiment, the height of the conical boss 13 protruding from the outer wall of the beam shaping body 10 is matched with the thickness of the first shielding layer 21 .

[0050] In this embodiment, the adaptation of the conical boss 13 and the conical hole on the first shielding layer makes the matching accuracy between the radiation shielding device and the beam shaping body higher and the radiation shielding effect better.

[0051] Embodiment 3

[0052] like Figure 6-9 As shown, the radiation shielding device 20 of this embodiment is different from that of the first embodiment in that a detachably mounted shielding unit 24 is provided on the first shielding layer 21 , and the material of the shielding unit 24 is the same as that of the first shielding layer 21 , wherein the beam exit hole 23 is provided on the shielding unit 24 .

[0053] In this embodiment, beam outlet holes 23 of different specifications can be configured on different shielding units 24. By replacing shielding units with beam outlet holes of different specifications, suitable beam specifications can be selected according to different conditions of patients. In this way, the application range of the radiation shielding device is wider through a simple structural design.

[0054] As a preferred implementation of this embodiment, Figure 6 , Figure 8 As shown, the first shielding layer 21 is provided with a mounting hole 26 adapted to the shielding unit 24. After the shielding unit 24 is adapted and installed with the mounting hole 26, the shielding unit is flush with both side end surfaces of the first shielding layer, one side of which is in contact with the beam shaping body, and the other side is in contact with the second shielding layer.

[0055] Preferably, in this embodiment, a positioning mechanism is provided between the first shielding layer 21 and the shielding unit 24. Fig. 9 As shown, the outer wall of the shielding unit 24 is provided with four positioning protrusions 25 extending radially outward at an edge near one end; Figure 8 As shown, a positioning groove 27 adapted to the positioning protrusion 25 is provided on one side of the first shielding layer 21 around the mounting hole 26. The positioning protrusion 25 and the positioning groove 27 form a positioning mechanism of this embodiment.

[0056] Preferably, in this embodiment, when the first shielding layer and the second shielding layer are in a separable fitting relationship, the positioning protrusion 25 is located at one end of the shielding unit close to the second shielding layer. The advantage of being arranged at this side is that when replacing the shielding unit, only the second shielding layer needs to be removed to directly replace the shielding unit. As an equivalent embodiment, the positioning protrusion 25 can also be located at one end of the shielding unit close to the beam shaping body.

[0057] When the first shielding layer and the second shielding layer are in an inseparable bonding relationship, the positioning protrusion 25 is located at one end of the shielding unit close to the beam shaping body.

[0058] In short, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A radiation shielding device, characterized in that: The invention comprises a first shielding layer for shielding neutron beam scattering and a second shielding layer for shielding gamma rays. The first shielding layer and the second shielding layer are arranged in close contact with each other. The first shielding layer is provided with a beam exit hole for accommodating the neutron beam to pass through. The second shielding layer is not provided with a beam exit hole at a position corresponding to the beam exit hole so as to remain intact.

2. The radiation shielding device according to claim 1, characterized in that The first shielding layer includes but is not limited to a boron-containing polyethylene plate, and the second shielding layer includes but is not limited to a lead plate.

3. The radiation shielding device according to claim 1 or 2, characterized in that: It also includes a shielding unit installed separately from the first shielding layer, the shielding unit is made of the same material as the first shielding layer, the beam outlet hole is arranged on the shielding unit, and the first shielding layer is provided with a mounting hole adapted to the shielding unit.

4. The radiation shielding device according to claim 3, characterized in that A positioning mechanism is provided between the first shielding layer and the shielding unit, and the positioning mechanism comprises: A positioning protrusion, wherein at least one positioning protrusion extending in a radial direction is provided at an edge of an outer wall of the shielding unit close to one end; Positioning groove: the first shielding layer is provided with a positioning groove adapted to the positioning protrusion.

5. A boron neutron capture therapy system, comprising at least a beam shaping body, wherein the beam shaping body is provided with a beam outlet, characterized in that: It also includes the radiation shielding device according to claim 1 or 2, wherein the radiation shielding device is arranged at the beam outlet of the beam shaping body, the position and size of the beam outlet hole are adapted to the beam outlet, the first shielding layer is located on a side close to the beam shaping body, and the second shielding layer is located on a side away from the beam shaping body.

6. The boron neutron capture therapy system according to claim 5, characterized in that: It also includes a collimator located in the beam shaping body, wherein the beam output end of the collimator protrudes from the outer wall of the beam shaping body, and the protruding part is a conical boss, and the beam outlet is located at the beam output end of the collimator.

7. The boron neutron capture therapy system according to claim 6, characterized in that: The beam exit hole on the first shielding layer is configured as a tapered hole matched with the tapered boss, and the height of the tapered boss protruding from the outer wall of the beam shaping body is matched with the thickness of the first shielding layer.

8. A boron neutron capture therapy system, comprising at least a beam shaping body, wherein the beam shaping body is provided with a beam outlet, characterized in that: It also includes the radiation shielding device according to claim 3 or 4, wherein the radiation shielding device is arranged at the beam outlet of the beam shaping body, the position of the beam outlet hole is adapted to the beam outlet, the first shielding layer is located on a side close to the beam shaping body, and the second shielding layer is located on a side away from the beam shaping body.

9. The boron neutron capture therapy system according to any one of claims 5 to 8, characterized in that: The first shielding layer is arranged in contact with the outer wall of the beam shaping body.

10. The boron neutron capture therapy system according to claim 9, characterized in that: The radiation shielding device and the beam shaping body are detachably matched.

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