CN211188827U - Radioactive source assembly for gamma knife - Google Patents

Abstract

The utility model discloses a gamma is radiation source subassembly for sword, it belongs to medical equipment technical field. The utility model comprises a source box and a radioactive source, wherein the source box comprises a body, and a plurality of source holes for placing the radioactive source are arranged on the body; the source holes comprise a central source hole and peripheral source holes, the central source hole is superposed with the central axis of the body, the peripheral source holes are arranged around the central source hole, and the peripheral source holes are inclined to the central axis of the body, so that gamma rays emitted by the radioactive source can be focused and irradiated on a target point. The utility model has the advantages that the emission source is integrated on the source box, thereby reducing the shielding difficulty of the whole machine, avoiding the ray leakage of the radioactive source and improving the safety; the radiation source has larger radiation dose, higher target focusing precision, reduced target area penumbra and optimized radiotherapy effect of the gamma knife; simple structure is exquisite, conveniently transports, and the dismouting is convenient, and equally, more targets in place to the protection of radiation source, and the security is higher, and the radiation source is also convenient for from the subassembly dismouting.

Description

Radioactive source assembly for gamma knife

Technical Field

The utility model belongs to the technical field of the medical equipment technique and specifically relates to a gamma is radiation source subassembly for sword is related to.

Background

The Gamma Knife (Gamma Knife) is the main treatment means of Stereotactic Radiosurgery, and is characterized by that according to the Stereotactic principle the pathological tissue can be selectively defined as target point, and the Gamma ray produced by cobalt-60 can be used for making one-step large-dose focusing irradiation so as to produce focal necrosis or functional change to attain the goal of curing disease.

The existing gamma knife equipment is spherical or fan-shaped, and radioactive sources are distributed on the equipment, and the distribution mode of the radioactive sources has a plurality of problems: 1. because the panel is too large, the radioactive sources are scattered, so that the shielding requirement is higher, and the risk of radioactive source ray leakage exists; 2. because the gamma knife equipment is in a spherical or sector shape, part of gamma rays emitted by the radioactive source are easily shielded by the source hole, so that the area penumbra of a target point is increased, the dosage of outgoing rays is small, the precision is insufficient, and the treatment effect is influenced; 3. the radioactive source is very inconvenient to disassemble and assemble.

SUMMERY OF THE UTILITY MODEL

Technical purpose

The utility model provides a not enough to above-mentioned prior art, the utility model provides a gamma is radiation source subassembly for sword aims at improving the radiation source and goes out the target focus precision of restrainting ray, optimizes out the dose utilization ratio of restrainting ray, reduces the target area penumbra, promotes radiation source dismouting convenience.

(II) technical scheme

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a radioactive source assembly for gamma knife is composed of a carrier and several radioactive sources in said carrier, and the gamma ray generated by said radioactive sources can be focused on target spot for radiotherapy.

The carrier is a source box which comprises a body, and a plurality of source holes for placing the radioactive source are formed in the body; the source holes comprise a central source hole and peripheral source holes, the central source hole is superposed with the central axis of the body, the peripheral source holes are arranged around the central source hole, and the peripheral source holes are inclined to the central axis of the body, so that gamma rays emitted by the radioactive source can be focused and irradiated on the target points.

The carrier for bearing the radioactive source is the source box, the integration level of the body structure is higher, and the layout area of the radioactive source is effectively reduced, thereby reducing the shielding difficulty; the radiation sources are arranged more compactly with respect to each other, so that the generation of penumbra in the radiation transmission path of the radiation sources can be reduced.

Cobalt-60 has strong radiation property, can cause alopecia, seriously damages cell tissues in human blood, causes leukopenia, causes blood system diseases such as aplastic anemia, seriously causes leukemia, and even directly has compact threat. Therefore, when the gamma knife device is used, firstly, the radiation amount of the gamma knife needs to be ensured to generate a treatment effect on diseases of a patient, and secondly, the radiation amount of the gamma knife needs to be controlled to avoid harm to the patient.

Further, the number of the source holes is 18-46. The number of source holes is limited in a certain range, and the radioactive sources and the source holes are in one-to-one correspondence, so that the number of the radioactive sources is limited, the total radiation amount of the radioactive sources is limited, and the total radiation amount is kept within a normal tolerance range of a human body. Of course, a change in the number of source apertures requires that the overall source cassette configuration and the mounting location configuration on the gamma knife be matched in design.

Furthermore, the peripheral source holes are circularly arranged on the peripheral side of the central source hole, the peripheral source holes are divided into two layers, namely an inner layer peripheral source hole and an outer layer peripheral source hole, the inner layer peripheral source hole and the central axis of the body form an included angle β, and the outer layer peripheral source hole and the central axis of the body form an included angle α.

Furthermore, the included angle α is 2-3 degrees, and the included angle β is 1-2 degrees, so that the inclination angle structure can enable radioactive rays generated by a radioactive source in the source box to focus on a public focus at a certain distance along the axial line of the source box to form a dose focus, and the requirement of accurate positioning radiotherapy is met.

Furthermore, the distance between the focus point of the gamma ray emitted by the radioactive source and the source box is 0.5-1.5 m. Because the radiation intensity is inversely proportional with the radiation distance, the utility model discloses according to the effect of self mechanism, compare the focus point of radiation source and have longer distance in current radiation source subassembly and radiation source, the radiation intensity can attenuate gradually at the radiation in-process, when reacing the patient health to accord with human tolerance, specifically, be the national standard that the dose equivalent rate is less than 2.5 mu Sv/h promptly.

Furthermore, the source box also comprises a gland, the gland is detachably connected to the upper part of the body, and the gland can be pressed against the top of the radioactive source when being connected to the body. When the gamma knife is used, the position can be adjusted to enable the focus point of the radioactive source to coincide with the target point, in the process, the radioactive source is easy to be separated from the source hole, when the gland is fixed on the upper portion of the body, one of the gland can prevent the radioactive source from falling off, and the other gland can be abutted against the top end of the radioactive source to prevent the radioactive source from being displaced and collided.

Further, the radioactive source includes at least one envelope having an open upper end, cobalt-60 particles disposed in the envelope, and an end cap sealingly attached to the envelope opening. The cobalt-60 particles were sealed in the envelope to ensure no gamma radiation leakage; moreover, the lower thickness of the bottom of the cladding ensures that gamma rays emitted by the cobalt-60 particles can be emitted from the bottom of the cladding. It should be noted that, to the sealed of end cover and involucrum, the utility model discloses in adopt argon arc to weld and seal up, can effectively protect weaker positions such as welding seam for the radiation source is whole to have sufficient intensity and hardness, has good shock resistance. Of course, other sealing means, such as other welding means, etc., may be used. Further, the weld must be continuous, completely sealed to ensure robustness, without the weld exceeding the envelope end face.

Further, the cladding comprises an inner cladding and an outer cladding, the cobalt-60 particles are arranged in the inner cladding, the inner cladding is arranged in the outer cladding, and the openings of the inner cladding and the outer cladding are positioned on the same side; the end cap includes an inner end cap and an outer end cap, the inner end cap is sealingly connected to the opening of the inner envelope, and the outer end cap is sealingly connected to the opening of the outer envelope. By arranging the two layers of cladding, the sealing performance and the shielding performance of the radioactive source to cobalt-60 particles are improved.

Furthermore, the inner diameter of the inner cladding is 3-6 mm, and the wall thickness of the inner cladding and the wall thickness of the outer cladding are 0.5-0.8 mm. By the arrangement, the wall thickness of the inner and outer cladding enables the radiation treatment effect of the radiation source to be optimal, and the volume of the inner cavity of the inner cladding is limited by combining the inner diameter of the inner cladding, so that the cobalt-60 input amount of each source hole is optimal. Meanwhile, because the inner diameter of the inner cladding limits the optimal cross-sectional dimension of the ray output by the bottom radioactive source, the dose of the ray output by the radioactive source is maximized and the penumbra is minimized.

Furthermore, the outer diameter of the outer wrapping shell is 6.5-8.5 mm, and the length of the outer wrapping shell is 20-30 mm. The size of outer envelope has decided the shape of single radiation source, and above-mentioned size makes the structure of single radiation source simpler exquisiteness, and convenient clamp is got, single radiation source of flip-chip, has promoted the simple operation nature.

Furthermore, the matching activity of the single radioactive source is 180-420 Ci, and the total activity of the radioactive source assembly for the gamma knife is 5000-12000 Ci. Reflection source activity influence its output dose, in order to make the utility model discloses can enough guarantee the radiotherapy effect, can ensure the security again, through the activity ratio of adjusting radiation source quantity, single reflection source, match and satisfy whole gamma sword equipment, the radioactivity output dose of radiation source subassembly promptly.

Furthermore, the inner diameter of the source hole is gradually reduced from top to bottom, the outer diameter of the cladding of the radioactive source is also gradually reduced from top to bottom, and the inner diameter of the bottom of the source hole is smaller than the outer diameter of the bottom of the cladding, so that the radioactive source is ensured not to fall out of the source hole. Generally, a bottom plate is required to be connected to the bottom of the body to prevent the radioactive source from falling out of the source hole, and in the scheme, the inner diameter of the bottom of the source hole is smaller than the outer diameter of the bottom of the cladding, namely, the radioactive source can be clamped in the source hole, so that the radioactive source is fixed, the use of the bottom plate is reduced, the structure of the source box is simplified, the connection relation of the source box is optimized, and the radioactive source assembly is more convenient to disassemble and assemble.

Further, the material of the body is tungsten alloy or depleted uranium. Because the shielding performance of the tungsten alloy or the depleted uranium is strong, the ray output by the radioactive source is collimated to a certain degree, the irradiation target spot is more optimized (the half shadow is smaller), and meanwhile, the shielding pressure of the whole machine is also reduced.

The utility model discloses assembly process needs get rid of each spare part surface burr, carries out sharp limit abate operation.

(III) advantageous effects

Compared with the prior art, the beneficial effects of the utility model reside in that: 1. the emission source is integrated on the source box, so that the shielding difficulty of the whole machine is reduced, the ray leakage of the radioactive source is effectively avoided, and the safety is improved; 2. the radiation source has larger radiation dose, higher target focusing precision, effectively reduces the penumbra of the target area and optimizes the radiotherapy effect of the gamma knife; 3. the utility model discloses simple structure is exquisite, and the convenient transportation, the dismouting is convenient, equally, more targets in place to the protection of radiation source, and the security is higher, and the radiation source is also convenient for from the subassembly dismouting.

Drawings

Fig. 1 is a bottom view of the utility model in use;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is a partial top cross-sectional view taken along line B-B of FIG. 2;

fig. 4 is a bottom view of the source box body of the present invention;

FIG. 5 is a front cross-sectional view taken along line C-C of FIG. 4;

FIG. 6 is a front cross-sectional view taken along line D-D of FIG. 4;

fig. 7 is a front sectional view of the source cartridge body of embodiment 2 of the present invention, taken along line D-D of fig. 4;

fig. 8 is a bottom view of the bottom plate of the present invention and a front cross-sectional view taken along line E-E of the bottom view;

fig. 9 is a front view and a plan view of the gland of the present invention;

FIG. 10 is a front cross-sectional view of the radiation source of the present invention;

description of reference numerals: 10-a source cartridge; 11-a body; 111-boss; 112-notch A; 113-notch B; 12-a source aperture; 121-central source aperture; 122-peripheral side source aperture; 122 a-inner perimeter source aperture; 122 b-outer layer peripheral side source aperture; 13-a gland; 131-cover holder; 132-notch C; 133-a limiting hole; 14-a base plate; 141-a through hole; 142-notch D; 20-a radioactive source; 21-cobalt-60 particles; 22-inner envelope; 23-an outer envelope; 24-inner end cap; 25-an outer end cap; 30-a shielding bar; 40-a collimator; 50-tungsten plate.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

The terms "a," "B," "a," "B," and the like are used merely to distinguish one description from another and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1

Referring to fig. 1-10, a radiation source assembly for a gamma knife comprises a source box 10 and 22 radiation sources 20 arranged in the carrier, wherein gamma rays emitted by the radiation sources 20 can be focused to irradiate a target spot for radiotherapy. The carrier is a source box 10, the source box 10 comprises a body 11, 22 source holes 12 for placing radioactive sources 20 are arranged on the body 11; the source apertures 12 include a central source aperture 121 and 21 peripheral source apertures 122, the central source aperture 121 coinciding with the central axis of the body 11, the peripheral source apertures 122 being arranged around the central source aperture 121, the peripheral source apertures 122 being inclined to the central axis of the body 11 so that gamma rays emitted by the radiation source 20 can be focused on the target point. Preferably, the body is cylindrical, of course, the body can also be in other shapes, such as a prism, and the number of edges is not limited; it may also be irregularly shaped. The body 11 is made of tungsten alloy.

The peripheral source holes 122 are circularly arranged on the peripheral side of the central source hole 121, the peripheral source holes 122 are two layers, namely seven inner layer peripheral source holes 122a and 14 outer layer peripheral source holes 122b, the inner layer peripheral source holes 122a form an included angle β with the central axis of the body 11, the outer layer peripheral source holes 122b form an included angle α with the central axis of the body 11, the included angle α is 2.2 degrees, and the included angle β is 1.2 degrees, the distance between the gamma-ray focus emitted by the radioactive source 20 and the source box 10 is 1.2 m.

The source box 10 further includes a pressing cover 13, the pressing cover 13 is detachably connected to the upper portion of the body 11, and the pressing cover 13 can press against the top of the radioactive source 20 when being connected to the body 11. As shown in fig. 9 (corresponding parts on other figures), specifically, two limiting holes 133 are formed on the gland 13, and after the radioactive source 20 is loaded into the source hole 12, a screw can be screwed into the body 11 through the limiting holes 133 for limiting and fixing; as shown in fig. 2 and 3, after the gland 13 is screwed, the gland 13 is pressed to abut against the top end of the radioactive source 20, so as to provide a downward acting force to the radioactive source 20, thereby ensuring that the radioactive source 20 is not separated from the body 11, and further, preventing the radioactive source 20 from being displaced in the source box 10 to collide with the cobalt-60 particles, thereby affecting the radiotherapy effect of the cobalt-60 particles 21. The material of the gland 13 is tungsten alloy. It should be noted that, furthermore, the pressing cover 13 is further provided with a cover holder 131 which is convenient to hold, so as to be convenient to take and place.

The radiation source 20 comprises an inner envelope 22, an outer envelope 23, an inner end cap 24, an outer end cap 25 and cobalt-60 particles 21 placed in the inner envelope 22, the inner envelope 22 and the outer envelope 23 each having an upper end open and being open at the same side, the openings of both being also located at a side close to the gland 13. The inner end cap 24 is seal-welded to the opening of the inner envelope 22 by argon arc welding, and the outer end cap 25 is seal-welded to the opening of the outer envelope 23 by argon arc welding. Preferably, the activity of the cobalt-60 particles 21 in a single radiation source 20 is matched to 180Ci, and the total activity of the radiation source assembly can be adjusted according to the change of the number of radiation sources, so as to match the gamma ray output dosage requirement required by the gamma knife device by changing the matching activity and the number of radiation sources 20.

The inner diameter of the inner envelope 22 is 5.2mm, and the thickness of the output end (bottom) and the side wall of the inner envelope 22 and the outer envelope 23 is 0.7 mm; the outer diameter of the outer envelope 23 was 8.0mm, and the length of the outer envelope 23 was set to 26 mm. It should be noted that the strength of the cladding needs to meet the requirements of the national standard GB 4075/C63535. The matching activity of the single radioactive source 20 is 300Ci, and the total activity of the radioactive source assembly for the gamma knife is 6600 Ci.

In this embodiment, a further improvement is provided by placing a spacer between the inner end cap 24 and the cobalt-60 particles 21, which will stabilize the compaction of the cobalt-60 particles 21 and adjust the loading based on the activity of the cobalt-60 particles 21. further, all cladding and spacer materials are 304 or 316L stainless steel to meet the requirements of corrosion and safety.

As for the structure of the radioactive source 20, the present invention can also be further improved as the Chinese patent No. CN 204257224U entitled "cobalt-60 radioactive source for Gamma-knife radiotherapy System". Specifically, a positioning ring groove for positioning is arranged on the outer wall of the outer cladding shell 23, so that the positioning precision of the radioactive source 20 during installation is ensured, and the safety of the radioactive source 20 in the transportation and use processes is effectively improved; the outer wall of the opening of the outer cladding shell 23 can be provided with a clamping ring groove which is convenient for clamping, so that the disassembly and assembly operation is facilitated, and the convenience and the working efficiency are improved. The structure is adapted when the number of envelopes is greater than two. Likewise, the shape and size of the enclosure may be adjusted according to different application requirements.

As shown in fig. 2, the shielding rod 30 is covered around the source box 10, the bottom of the outer wall of the body 11 is provided with a boss 111, and the boss 111 is detachably connected with the shielding rod 30. The lower side of the source box 10 is provided with a collimator 40, and the top of the collimator 40 is communicated with the bottom of the source hole 12 and is used for guiding gamma rays emitted by the radioactive source 20. In this embodiment, further improvement is made, a tungsten plate 50 is disposed between the source box 10 and the collimator 40, so as to enhance the shielding performance of the whole machine, the outgoing beam γ rays of the radioactive source 20 can smoothly pass through the tungsten plate 50, and also have a certain collimation effect on the γ rays, thereby improving the focusing accuracy, maximizing the radiation dose, and reducing the penumbra.

As shown in fig. 4 to 6, it can be seen that the bottom of the body 11 is provided with a shallow groove, and the shallow groove is communicated with the source hole 12 and is used for installing the bottom plate 14. As shown in fig. 8, through holes 141 corresponding to the number of the active holes 12 are formed on the surface of the substrate 14, and the through holes 141 are used for passing gamma rays emitted from the cobalt-60 particles 21; the bottom plate 14 is also provided with screw holes for fastening the bottom plate 14 to the body 11 by screws. It should be noted that, as shown in fig. 8, in this embodiment, three screw holes are formed in the bottom plate 14, and the screw holes are arranged in an isosceles triangle, and an included angle between a connecting line between the screw holes located at the left and right sides and the center of the bottom plate 14 and a connecting line between the screw holes located at the top side and the center of the bottom plate 14 is 103 °, so that the bottom plate 14 is integrally fastened to the lower portion of the body 11, and the radiation source 20 is prevented from moving and colliding with the source hole 12.

Example 2

This embodiment only illustrates the differences from the previous embodiments, and the same contents are not repeated.

Referring to fig. 7, a radiation source assembly for gamma knife comprises a source box 10 having 32 source holes 12, wherein the peripheral source holes 122 are circularly arranged on the peripheral side of the central source hole 121, the peripheral source holes 122 are two layers, namely inner peripheral source holes 122a and outer peripheral source holes 122b, the inner peripheral source holes 122a form an included angle β with the central axis of the body 11, the outer peripheral source holes 122b form an included angle α with the central axis of the body 11, the included angle α is 2.5 degrees, and the included angle β is 1.5 degrees, so that the distance between the target points focused by gamma rays emitted from all the radiation sources 20 and the source box 10 is 0.9 m.

The inner diameter of the inner envelope 22 is 4.5mm, and the thickness of the output end (bottom) and the side wall of the inner envelope 22 and the outer envelope 23 is 0.5 mm; the outer diameter of the outer envelope 23 was 6.5mm, and the length of the outer envelope 23 was set to 24 mm. The activity match of cobalt-60 particles 21 in a single radiation source 20 is 180Ci, and the total activity of the radiation source assembly for a gamma knife is 5760 Ci.

The inside diameter of the source hole 12 is gradually reduced from top to bottom, the outside diameter of the outermost envelope of the radioactive source 20 is also gradually reduced from top to bottom, and the inside diameter of the bottom of the source hole 12 is smaller than the outside diameter of the bottom of the envelope of the radioactive source 20, so that the radioactive source 20 is ensured not to fall out of the source hole 12. Fig. 7 is a schematic diagram illustrating a modification of the present embodiment.

The solution of this embodiment makes the source box 10 no longer need the bottom plate 14, simplifies the structure, because the inner diameter of the source hole 12 is continuously reduced, the radioactive source 20 can be directly clamped in the source hole 12 when being pressed down, and when the radioactive source 20 is pressed into a certain degree, the larger the restraining force of the inner wall of the source hole 12, the less easily the radioactive source is released from the source hole 12, and possibly, the pressing cover 13 may even be no longer needed, further simplifying the structure of the source box 10. Meanwhile, the convenience of assembling and disassembling the radioactive source 20 can be further optimized.

Referring to fig. 1, 2, 5 and 8, a notch D142 is provided at one side edge of the bottom plate 14, and correspondingly, a notch B113 is provided on one side wall of the shallow groove at the bottom of the body 11; when the bottom plate 14 is installed, the notches D142 and B113 are aligned, so that the corresponding screw holes on the bottom plate 14 and the body 11 are aligned, and the screws can be smoothly screwed.

Referring to fig. 2 to 5 and 9 again, a notch C132 is formed at an edge of one side of the gland 13, and correspondingly, a notch a112 is formed on a side wall of the empty groove of the body 11 for placing the gland 13; when the gland 13 is installed, the notch a112 and the notch C132 are aligned, so that the limiting hole 133 on the gland 13 and the corresponding screw hole on the body 11 are aligned, and the screw can be smoothly screwed at the moment.

It should be noted that, in the present invention, it is very important and necessary to align the screw holes. Because body 1 is last to be opened has a plurality of source holes 12, if do not aim at the screw hole, probably the screw is inserted in source hole 12, can support and press on radiation source 20, can push up askew radiation source 20 for its beam outgoing line deviates the target point, and the focusing accuracy descends, has increased the target area penumbra, leads to target point department radiotherapeutic dose not enough, in a word, the utility model discloses in the setting of four breachs, it is very big.

Example 3

This embodiment only illustrates the differences from the previous embodiments, and the same contents are not repeated.

A radioactive source assembly for gamma knife is composed of a source box (10) consisting of 46 source holes (12), two layers of peripheral source holes (122) arranged around central source hole (121), an included angle β between said source holes (122a) and central axis of main body (11), an included angle α between source holes (122b) and central axis of main body (11), an included angle α of 2 deg. and an included angle β of 1 deg. and a distance of 0.5m between the target point of gamma ray focus emitted from radioactive source (20) and source box (10).

The inner diameter of the inner cladding 22 is 3mm, and the thickness of the output end (bottom) and the side wall of the inner cladding 22 and the outer cladding 23 is 0.8 mm; the outer diameter of the outer casing 23 is 6.5mm, and the length of the outer casing 23 is 20 mm; the activity match of cobalt-60 particles 21 in a single radiation source 20 is 261Ci, and the total activity of the radiation source assembly for a gamma knife is 12000 Ci.

Example 4

This embodiment only illustrates the differences from the previous embodiments, and the same contents are not repeated.

A radioactive source assembly for gamma knife is composed of a source box (10) with 18 source holes (12), two layers of peripheral source holes (122) arranged around central source hole (121), an included angle (β) between central axis of main body (11) and peripheral source holes (122a, 122b), an included angle (α), α, β and 1 m for gamma ray emitted from radioactive source (20) and a distance (1.5 m) between the target point of gamma ray focus and source box (10).

The inner diameter of the inner envelope 22 is 6mm, and the thickness of the output end (bottom) and the side wall of the inner envelope 22 and the outer envelope 23 is 0.625 mm; the outer diameter of the outer casing 23 is 8.5mm, and the length of the outer casing 23 is set to be 30 mm; the activity of cobalt-60 particles 21 in a single radiation source 20 is matched to 420Ci, and the total activity of the radiation source assembly for a gamma knife is 7560 Ci.

Claims (13)

1. A radioactive source assembly for a gamma knife comprises a carrier and a plurality of radioactive sources (20) arranged in the carrier, wherein gamma rays emitted by the radioactive sources (20) can be focused and irradiated on a target point to carry out radiotherapy; the method is characterized in that:

the carrier is a source box (10), the source box (10) comprises a body (11), and a plurality of source holes (12) for placing the radioactive source (20) are formed in the body (11); the source holes (12) comprise central source holes (121) and peripheral source holes (122), the central source holes (121) coincide with the central axis of the body (11), the peripheral source holes (122) are arranged around the central source holes (121), and the peripheral source holes (122) are inclined to the central axis of the body (11) so that gamma rays emitted by the radioactive source (20) can be focused and irradiated on target points.

2. A radiation source assembly for a gamma knife according to claim 1 wherein: the number of the source holes (12) is 18-46.

3. The radiation source assembly for gamma knife according to claim 1, wherein the peripheral side source holes (122) are arranged in a circle around the central source hole (121), and the peripheral side source holes (122) are two layers, namely an inner layer peripheral side source hole (122a) and an outer layer peripheral side source hole (122b), the inner layer peripheral side source hole (122a) forms an included angle β with the central axis of the body (11), and the outer layer peripheral side source hole (122b) forms an included angle α with the central axis of the body (11).

4. The gamma ray source assembly of claim 3 wherein said included angle α is 2-3 ° and said included angle β is 1-2 °.

5. The radiation source assembly for a gamma knife according to claim 1, 3 or 4 wherein: the distance between the gamma ray focus point emitted by the radioactive source (20) and the source box (10) is 0.5-1.5 m.

6. A radiation source assembly for a gamma knife according to claim 1 wherein: the source box (10) further comprises a gland (13), the gland (13) is detachably connected to the upper portion of the body (11), and the gland (13) can be pressed against the top of the radioactive source (20) when being connected to the body (11).

7. A radiation source assembly for a gamma knife according to claim 1 wherein: the radioactive source (20) includes at least one envelope open at an upper end, cobalt-60 particles (21) disposed in the envelope, and an end cap sealingly attached to the envelope opening.

8. The radiation source assembly for a gamma knife according to claim 7 wherein: the cladding comprises an inner cladding (22) and an outer cladding (23), the cobalt-60 particles (21) are arranged in the inner cladding (22), the inner cladding (22) is arranged in the outer cladding (23), and the openings of the inner cladding (22) and the outer cladding (23) are positioned on the same side; the end caps comprise inner end caps (24) and outer end caps (25), the inner end caps (24) are connected with the openings of the inner shell (22) in a sealing mode, and the outer end caps (25) are connected with the openings of the outer shell (23) in a sealing mode.

9. The radiation source assembly for a gamma knife according to claim 8 wherein: the inner diameter of the inner cladding (22) is 3-6 mm; the wall thickness of the inner cladding (22) and the outer cladding (23) is 0.5-0.8 mm.

10. The radiation source assembly for a gamma knife according to claim 8 wherein: the outer diameter of the outer casing (23) is 6.5-8.5 mm, and the length of the outer casing is 20-30 mm.

11. A radiation source assembly for a gamma knife according to claim 1 or claim 8 wherein: the matching activity of the single radioactive source (20) is 180-420 Ci, and the total activity of the radioactive source assembly for the gamma knife is 5000-12000 Ci.

12. A radiation source assembly for a gamma knife according to claim 7 or claim 8 wherein: the inner diameter of the source hole (12) is gradually reduced from top to bottom, the outer diameter of the cladding of the radioactive source (20) is also gradually reduced from top to bottom, and the inner diameter of the bottom of the source hole (12) is smaller than the outer diameter of the bottom of the cladding, so that the radioactive source (20) is ensured not to fall out of the source hole (12).

13. A radiation source assembly for a gamma knife according to claim 1 wherein: the body (11) is made of tungsten alloy or depleted uranium.

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