Compact multi-chamber proton therapy system based on shared bunch

Abstract

The invention relates to the field of medical equipment, and provides a compact multi-chamber proton treatment system based on a shared beam line, and the system comprises a fixed beam transmission line which is used for guiding the movement direction of a proton beam into a vertical direction; the rotating beam transmission line is used for guiding the movement direction of the proton beam into the horizontal direction; one end of the fixed beam transmission line is connected with the proton cyclotron, the other end of the fixed beam transmission line is connected with one end of the rotary beam transmission line, and the other end of the rotary beam transmission line is in butt joint with a plurality of treatment rooms; the rotating beam transmission line rotates around a central axis extending in the vertical direction. According to the invention, the proton beam can be safely, efficiently and accurately transmitted to each treatment room, and a fixed beam transmission system and a rotating rack do not need to be independently arranged for each treatment room, so that the beam control assembly and the system occupied area of the multi-room particle treatment device are minimized, and the number of treated patients can be remarkably increased.

Description

Technical Field

[0001] The present invention relates to the field of medical equipment, and in particular to a compact multi-chamber proton therapy system based on a shared beam line. Background Art

[0002] In the past three decades, proton therapy has made great progress and has become a better choice for radiotherapy for certain types of cancer. Compared with standard radiotherapy, proton therapy can not only improve the conformality of tumor dose distribution, but also reduce the radiation of normal tissues and organs around the tumor, reduce short-term and long-term side effects, help improve patients' survival rate and quality of life, and reduce secondary cancer complications.

[0003] Traditional commercial particle therapy systems are mainly composed of three parts. The first part is an accelerator that produces high-energy charged particles, including: linear accelerator, cyclotron, synchrotron or synchrocyclotron; the second part is the beam transmission system, including: energy selection system and fixed beam transmission line; the third part is a rotating gantry, which can rotate clockwise or counterclockwise around the reverse extension line of the fixed beam line passing through the isocenter, so as to irradiate the tumor at different angles, improve the conformality of the tumor dose distribution, and better protect the normal tissues and organs around the tumor. Therefore, in the existing commercial equipment, each treatment room of the particle beam transmission system has its own fixed beam transmission system and rotating gantry.

[0004] In particular, due to the large magnetic stiffness of protons, the magnetic stiffness of 250 MeV is 2.43 T / m, which leads to a large deflection radius of the deflection dipole iron. At the same time, the treatment head requires a certain length of source-axis distance, so the usual proton rotating frame is large, with a diameter and length of about 10 m. Therefore, compared with traditional medical linear accelerator radiotherapy equipment, proton therapy equipment requires a larger floor space. In addition, the average floor space of a single treatment room equipped with proton therapy equipment is about 200 square meters, which is three times the average floor space of a single treatment room equipped with medical linear accelerator radiotherapy equipment, limiting the popularization of proton radiotherapy.

[0005] Recent studies have shown that most tumor particle beam therapies can be achieved by replacing the rotating gantry with a fixed beamline. Among them, the patient is treated in an upright position and can rotate around the fixed beam. Therefore, the upright treatment method can reduce the need for a rotating gantry and reduce the scale of proton therapy. Traditional cyclotron-based single-room equipment does not have a rotating gantry and requires a fixed beam transport system, including: an extraction matching section for focusing from the accelerator to the center of the degrader, an energy degrader to reduce the beam energy, and an energy selection system. Among them, the energy selection system consists of a collimator to control the beam emittance, a dipole iron to deflect the beam, a focusing / defocusing quadrupole iron, and a momentum selection slit to reduce energy dispersion. Therefore, a cyclotron-based single-room fixed beam transport system requires at least 2 deflection magnets and more than 10 quadrupole irons. Compared with a single treatment room, the number of dipole irons and quadrupole irons required for multiple treatment rooms increases exponentially, and the corresponding number of power supplies, water cooling, and vacuum systems also increases exponentially. In addition, a lot of space is required, resulting in a large footprint and high cost. Summary of the invention

[0006] The technical problem to be solved by the present invention is that a multi-chamber treatment system based on a fixed beam transmission system occupies a large area and requires a large number of beam control components.

[0007] In order to solve the above technical problems, the present invention is implemented by the following technical solutions: A compact multi-room proton therapy system based on a shared beam line comprises: a fixed beam transmission line for guiding the movement direction of a proton beam to a vertical direction; a rotating beam transmission line for guiding the movement direction of a proton beam to a horizontal direction; one end of the fixed beam transmission line is connected to a proton cyclotron accelerator, the other end of the fixed beam transmission line is connected to one end of a rotating beam transmission line, and the other end of the rotating beam transmission line is connected to a plurality of treatment rooms; the rotating beam transmission line rotates around a central axis extending in a vertical direction.

[0008] Furthermore, the fixed beam transmission line is also used to converge the proton beam, change the energy of the proton beam and control the emittance of the proton beam; the rotating beam transmission line is also used to converge the proton beam, reduce the energy dispersion of the proton beam, correct the proton beam and control the distribution of the proton beam.

[0009] Furthermore, the fixed beam transmission line includes a three-in-one quadrupole iron, a 90° deflection magnet, an energy degrader and a plurality of collimators connected in series on the first vacuum tube in sequence; one end of the first vacuum tube close to the three-in-one quadrupole iron is connected to the proton cyclotron accelerator; the rotating beam transmission line includes: a first converging section, a deflection section, a second converging section and a control section in sequence; the first converging section is close to the collimator, and the control section is close to the treatment room; the first converging section includes: a two-in-one quadrupole iron; the deflection section includes: a momentum selection slit, a bidirectional correction magnet, a plurality of 45° deflection magnets and a plurality of two-in-one quadrupole irons, the plurality of two-in-one quadrupole irons are located between two adjacent 45° deflection magnets, and the dynamic The momentum selection slit and the bidirectional correction magnet are successively located between two adjacent two-in-one quadrupoles, and the sum of the deflection angles of the multiple 45° deflection magnets is 90°; the second converging section includes: a bidirectional correction magnet and a multiple two-in-one quadrupoles, and the bidirectional correction magnet is located between two adjacent two-in-one quadrupoles; the control section includes: a multiple scanning magnets; the momentum selection slit, the scanning magnet, a multiple bidirectional correction magnet, a multiple two-in-one quadrupoles and a multiple 45° deflection magnets are connected in series on the second vacuum tube, an end of the second vacuum tube close to the first converging section is connected to an end of the first vacuum tube close to the collimator, and an end of the second vacuum tube close to the control section is connected to the treatment room.

[0010] Furthermore, in the fixed beam transmission line, the number of collimators is 2, and the deflection angle of the 90° deflection magnet is 90°; in the deflection section, the number of 45° deflection magnets is 2, and the number of two-in-one quadrupoles is 2; the deflection angles of the two 45° deflection magnets are both 45°; in the second converging section, the number of two-in-one quadrupoles is 2, and in the control section, the number of scanning magnets is 2.

[0011] Furthermore, the plurality of treatment rooms are distributed on a rotation track of one end of the second vacuum tube close to the scanning magnet.

[0012] Furthermore, a plurality of treatment rooms are distributed at equal intervals; the number of treatment rooms is 8 to 12.

[0013] Furthermore, the multi-chamber proton therapy system also includes: an upper shielding body, an outer shielding wall, an inner shielding wall, a supporting mechanism, a rotating mechanism and a lower shielding body; the outer shielding wall surrounds the inner shielding wall, the supporting mechanism, the rotating mechanism, the lower shielding body and the outside of multiple treatment rooms; the rotating mechanism is arranged on the lower shielding body, the supporting mechanism is arranged on the rotating mechanism, and the rotating beam transmission line is fixed on the supporting mechanism; the inner shielding wall is located on the supporting mechanism and surrounds the outside of the rotating beam transmission line; the upper shielding body is located above the outer shielding wall and the inner shielding wall, and the fixed beam transmission line and the proton cyclotron are fixed on the upper shielding body.

[0014] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The proton beam can be safely, efficiently and accurately transmitted to each treatment room by rotating a proton beam transmission line. There is no need to equip each treatment room with a fixed beam transmission system and a rotating rack, thereby minimizing the beam control components (including machinery, magnets, power supply, water cooling and vacuum systems, etc.) and system footprint of the multi-chamber particle therapy device, which can significantly increase the number of patients treated.

[0015] 2. The fixed beam transmission line is set vertically downward, so that the direction of the radiation generated after energy reduction is also downward, thereby reducing the radiation shielding requirements and the risk of radiation leakage.

[0016] 3. The fixed beam transmission line and the rotating beam transmission line together form an asymmetric beam transmission, which increases the emittance of the beam transmission system by 100 πmmmrad, the transmission efficiency and the momentum divergence, and realizes the function of a single beam transmission system working in multiple treatment rooms. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of the structural relationship between a fixed beam transmission line and a rotating beam transmission line provided in an embodiment of the present invention; Figure 2 A diagram showing the positions of a rotating beam transmission line provided in an embodiment of the present invention when the rotating beam transmission line is rotated to 8 different angles; Figure 3 Beam optical diagrams of a fixed beam transmission line and a rotating beam transmission line provided by an embodiment of the present invention; Figure 4 A front view of a multi-chamber proton therapy system provided by an embodiment of the present invention; Figure 5 A top view of the distribution of eight treatment rooms in a multi-room proton therapy system provided by an embodiment of the present invention; Figure 6 A top view of the distribution of 12 treatment rooms in a multi-room proton therapy system provided in an embodiment of the present invention.

[0019] Marks and corresponding parts names in the attached drawings: 10- proton cyclotron, 20- fixed beam transmission line, 30- rotating beam transmission line, 21- three-in-one quadrupole iron, 22- 90° deflection magnet, 23- wedge degrader, 24- collimator, 32- two-in-one quadrupole iron; 33- 45° deflection magnet; 34- momentum selection slit; 35- bidirectional correction magnet; 36- scanning magnet; 37- treatment chair, 38- isocenter, 41- position of rotatable beam transmission line after rotating 0°, 42- position of rotatable beam transmission line after rotating 45°, 43- The position of the rotatable beam transmission line after rotating 90°, 44 - the position of the rotatable beam transmission line after rotating 135°, 45 - the position of the rotatable beam transmission line after rotating 180°, 46 - the position of the rotatable beam transmission line after rotating 225°, 47 - the position of the rotatable beam transmission line after rotating 270°, 48 - the position of the rotatable beam transmission line after rotating 325°, 51 - upper shielding body; 52 - outer shielding wall; 53 - inner shielding wall; 54 - supporting mechanism; 55 - rotating mechanism; 56 - lower shielding body. DETAILED DESCRIPTION

[0020] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0021] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one of ordinary skill in the art that these specific details are not necessarily employed to practice the present invention. In other embodiments, in order to avoid obscuring the present invention, well-known structures, circuits, materials, or methods are not specifically described.

[0022] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. In addition, it will be appreciated by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0023] In the description of the present invention, the directions or positional relationships indicated by terms such as “front”, “rear”, “left”, “right”, “up”, “down”, “vertical”, “horizontal”, “high”, “low”, “inside” and “outside” 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. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present invention.

[0024] Example: A compact multi-room proton therapy system based on a shared beamline is proposed, comprising Figure 1 The proton cyclotron 10, the fixed beam transmission line 20 and the rotating beam transmission line 30 are shown. The proton cyclotron 10 is used to generate a high-energy (230Me-250 MeV) proton beam; the fixed beam transmission line 20 is used to converge the proton beam, guide the movement direction of the proton beam to a vertical direction, change the energy of the proton beam and control the emittance of the proton beam; the rotating beam transmission line 30 is used to converge the proton beam, guide the movement direction of the proton beam to a horizontal direction, reduce the energy dispersion of the proton beam, correct the proton beam and control the distribution of the proton beam.

[0025] Specifically, Figure 1 The fixed beam transmission line 20 shown is composed of a three-in-one quadrupole iron 21 (composed of three series-connected quadrupole irons), a 90° deflection magnet 22, a wedge-shaped energy degrader 23, and three collimators 24, which are sequentially connected in series to a first vacuum tube. One end of the first vacuum tube close to the three-in-one quadrupole iron 21 is connected to the proton cyclotron 10. The proton beam released by the proton cyclotron 10 in the horizontal direction enters the fixed beam transmission line 20. On the fixed beam transmission line 20, the three-in-one quadrupole iron 21 first focuses the proton beam, and then the focused proton beam enters the 90° deflection magnet 22, which deflects the movement direction of the proton beam from the horizontal direction to the vertical downward direction; the deflected proton beam passes through the wedge-shaped energy degrader 23 to change its energy, and the thickness of the wedge-shaped energy degrader 23 varies according to the proton beam energy corresponding to the patient's tumor depth. Finally, the proton beam passes through three collimators 24 to increase the emittance of the fixed beam transmission line 20 to 100πmmmrad, and finally reaches the rotation control point.

[0026] Continue to refer Figure 1The rotating beam transmission line 30 comprises a first convergence section, a deflection section, a second convergence section and a control section connected in sequence. The first convergence section comprises a two-in-one quadrupole iron 32, the deflection section is composed of a 45° deflection magnet 33, a two-in-one quadrupole iron 32, a momentum rotation slit, a bidirectional correction magnet 35 and a 45° quadrupole iron connected in sequence, the second convergence section is composed of a two-in-one quadrupole iron 32, a bidirectional correction magnet 35 and a two-in-one quadrupole iron 32 connected in sequence, and the control end is composed of two scanning magnets 36 connected in series. The protons released by the fixed beam transmission line 20 first enter the first convergence section and are focused by the two-in-one quadrupole iron 32 of the first convergence section. The focused proton beam enters the deflection section, where the first 45° deflection magnet 33 deflects the direction of motion of the proton beam by 45°, and then one of the two pairs of symmetrically arranged two-in-one quadrupole irons 32 gathers the proton beam, and then the momentum divergence of the proton beam is reduced to within ±3% by the momentum rotation slit, and then the proton beam is corrected by the two-way correction magnet 35, and the corrected proton beam is focused by the second pair of two-in-one quadrupole irons 32, and finally the focused proton beam is deflected by the second 45° deflection magnet 33 by 45° so that the direction of motion of the proton beam is changed to the horizontal direction. The deflected proton beam enters the second convergence section, and firstly, one of the two-in-one quadrupole irons 32 in the second convergence section focuses the proton beam for the first time, and then the proton beam after the first focusing is corrected by the two-way correction magnet 35, and the corrected proton beam is focused by the second two-in-one quadrupole iron 32 and sent to the control section. In the control section, the trajectory and distribution of the proton beam are controlled by two scanning magnets 36. The five pairs of two-in-one quadrupoles 32, two 45° deflection magnets 33, one momentum selection slit 34, two bidirectional correction magnets 35 and two scanning magnets 36 in the rotating beam transmission line 30 are connected in series on the second vacuum tube in the above order. The end of the second vacuum tube close to the first convergence section is connected to the end of the first vacuum tube close to the collimator 24 at the rotation control point, and the end of the second vacuum tube close to the control section is connected to the treatment room. The proton beam is finally output to the treatment chair 37 in the treatment room to complete the pencil beam scanning of the tumor at the treatment chair 37. The rotating beam transmission line 30 rotates clockwise or counterclockwise 0-360° around the vertical central axis passing through the rotation control point. The rotation can realize the safe, efficient and accurate transmission of the proton beam to each treatment room. The position 41 after the rotatable beam transmission line is rotated by 0°, the position 42 after the rotatable beam transmission line is rotated by 45°, the position 43 after the rotatable beam transmission line is rotated by 90°, the position 44 after the rotatable beam transmission line is rotated by 135°, the position 45 after the rotatable beam transmission line is rotated by 180°, the position 46 after the rotatable beam transmission line is rotated by 225°, the position 47 after the rotatable beam transmission line is rotated by 270°, and the position 48 after the rotatable beam transmission line is rotated by 325°. Figure 2 shown. Figure 3 The beam optics of the fixed beam transmission line 20 and the rotating beam transmission line 30 are demonstrated. The beam spot size at the energy degrader exit is controlled within 1 mm, the emittance is 100πmmmrad, the momentum divergence is ±3%, and the beam spot 2 Sigma at the isocenter 38 is 10 mm (in vacuum).

[0027] Furthermore, the compact multi-chamber proton therapy system based on shared beamline proposed in this embodiment has Figure 1 In addition to the proton cyclotron 10, the fixed beam transmission line 20 and the rotating beam transmission line 30, the proton cyclotron 10 also has an upper shielding body 51, an outer shielding wall 52, an inner shielding wall 53, a supporting mechanism 54, a rotating mechanism 55 and a lower shielding body 56. Figure 4 As shown, the rotating mechanism 55 is located on the lower shielding body 56, the supporting mechanism 54 is located on the rotating mechanism 55, and the inner shielding wall 53 is located on the supporting mechanism 54. The outer shielding wall 52 surrounds the inner shielding wall 53, the supporting mechanism 54, the rotating mechanism 55 and the outer shielding wall 52, and the upper shielding body 51 is located above the inner shielding wall 53 and the outer shielding wall 52. The proton beam cyclotron fixed and fixed beam transmission lines 20 are both fixed on the upper shielding body 51, one end of the rotating beam transmission line 30 close to the first convergence section is connected to one end of the fixed beam transmission line 20 close to the collimator 24 at the rotation control point, and the second convergence section and the control section of the rotating beam transmission line 30 are connected to the supporting mechanism 54. It should be noted that a single three-in-one quadrupole iron 21 weighs about 0.5 tons, a single 45° deflection magnet 33 weighs about 5 tons, and the entire rotatable beam transmission line 30 is mainly composed of 10 quadrupole irons and 2 dipole irons, with a total weight of about 15 tons, which is significantly lower than the weight of a traditional rotating gantry of 100-300 tons. Therefore, the rotatable beam transmission line 30 can be rotated from one treatment room to another within 30 seconds.

[0028] The rotating mechanism 55 drives the supporting mechanism 54, the rotating beam transmission line 30 and the inner shielding wall 53 to rotate clockwise or counterclockwise by 0-360 degrees. Each treatment room is located in the interlayer annular space between the inner shielding wall 53 and the outer shielding wall 52, and is evenly spaced in the interlayer annular space. The rotating beam transmission line 30 transmits the proton beam to each treatment room safely, efficiently and accurately through rotation. The distribution positions of the 8 treatment rooms are as follows: Figure 5 As shown, the size of each treatment room is 5 m x 4 m; the distribution positions of the 12 treatment rooms are as follows Figure 6As shown in the figure, the size of each treatment room is 4.0 m x 4.0 m. 8-12 treatment rooms share one beam transmission line, which greatly reduces the number of control components and floor space compared to configuring a separate beam transmission line and rotating gantry for each treatment room. At the same time, about 3,000-4,500 patients can be treated each year, improving patient throughput.

[0029] The above specific implementation methods further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific implementation methods of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A compact multi-chamber proton therapy system based on a shared beamline, characterized in that: include: A fixed beam transmission line (20) is used to guide the movement direction of the proton beam to a vertical direction; A rotating beam transmission line (30) is used to guide the movement direction of the proton beam to a horizontal direction; One end of the fixed beam transmission line (20) is connected to the proton cyclotron (10), the other end of the fixed beam transmission line (20) is connected to one end of the rotating beam transmission line (30), and the other end of the rotating beam transmission line (30) is connected to a plurality of treatment rooms; the rotating beam transmission line (30) rotates around a central axis extending in a vertical direction.

2. A compact multi-room proton therapy system based on a shared beamline according to claim 1, characterized in that: The fixed beam transmission line (20) is also used to focus the proton beam, change the energy of the proton beam and control the emittance of the proton beam; The rotating beam transmission line (30) is also used to converge the proton beam, reduce the energy dispersion of the proton beam, correct the proton beam and control the distribution of the proton beam.

3. A compact multi-room proton therapy system based on a shared beamline according to claim 2, characterized in that: The fixed beam transmission line (20) comprises a three-in-one quadrupole iron (21), a 90° deflection magnet (22), a wedge-shaped energy degrader (23), and a plurality of collimators (24) which are sequentially connected in series on a first vacuum tube; one end of the first vacuum tube close to the three-in-one quadrupole iron (21) is connected to a proton cyclotron accelerator (10); The rotating beam transmission line (30) comprises, in sequence: a first converging section, a deflection section, a second converging section and a control section; the first converging section is close to the collimator (24), and the control section is close to the treatment room; the first converging section comprises: a two-in-one quadrupole iron (32); the deflection section comprises: a momentum selection slit (34), a two-way correction magnet (35), a plurality of 45° deflection magnets (33) and a plurality of two-in-one quadrupole irons (32); the plurality of two-in-one quadrupole irons (32) are located between two adjacent 45° deflection magnets (33); the momentum selection slit (34) and the two-way correction magnet (35) are located in sequence between two adjacent two-in-one quadrupole irons (32); the plurality of 45° deflection magnets ( The sum of the deflection angles of the two-in-one quadrupoles (33) is 90°; the second converging section comprises: a bidirectional correction magnet (35) and a plurality of two-in-one quadrupoles (32), wherein the bidirectional correction magnet (35) is located between two adjacent two-in-one quadrupoles (32); the control section comprises: a plurality of scanning magnets (36); the momentum selection slit (34), the scanning magnet (36), the plurality of bidirectional correction magnets (35), the plurality of two-in-one quadrupoles (32) and the plurality of 45° deflection magnets (33) are connected in series on the second vacuum tube, an end of the second vacuum tube close to the first converging section is connected to an end of the first vacuum tube close to the collimator (24), and an end of the second vacuum tube close to the control section is connected to the treatment room.

4. A compact multi-chamber proton therapy system based on a shared beamline according to claim 3, characterized in that: In the fixed beam transmission line (20), the number of collimators (24) is 2, and the deflection angle of the 90° deflection magnet (22) is 90°; In the deflection section, the number of 45° deflection magnets (33) is 2, and the number of two-in-one quadrupole irons (32) is 2; the deflection angles of the two 45° deflection magnets (33) are both 45°; In the second convergence section, the number of two-in-one quadrupole irons (32) is 2. In the control section, the number of scanning magnets (36) is 2.

5. A compact multi-chamber proton therapy system based on a shared beamline according to claim 4, characterized in that: The plurality of treatment rooms are distributed on a rotation track of one end of the second vacuum tube close to the scanning magnet (36).

6. A compact multi-chamber proton therapy system based on a shared beamline according to claim 5, characterized in that: Multiple treatment rooms are evenly spaced; the number of treatment rooms is 8 to 12.

7. A compact multi-chamber proton therapy system based on a shared beamline according to any one of claims 1 to 6, characterized in that: The invention also comprises: an upper shielding body (51), an outer shielding wall (52), an inner shielding wall (53), a supporting mechanism (54), a rotating mechanism (55) and a lower shielding body (56); the outer shielding wall (52) surrounds the inner shielding wall (53), the supporting mechanism (54), the rotating mechanism (55), the lower shielding body (56) and the outside of a plurality of treatment rooms; the rotating mechanism (55) is arranged on the lower shielding body (56), the supporting mechanism (54) is arranged on the rotating mechanism (55), and the rotating beam transmission line (30) is fixed on the supporting mechanism (54); the inner shielding wall (53) is located on the supporting mechanism (54) and surrounds the outside of the rotating beam transmission line (30); the upper shielding body (51) is located above the outer shielding wall (52) and the inner shielding wall (53), and the fixed beam transmission line (20) and the proton cyclotron accelerator (10) are fixed on the upper shielding body (51).

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