Multi-angle particle treatment system without rotating rack and use method thereof

Abstract

The invention discloses a multi-angle particle therapy system without a rotating rack and a using method thereof, and relates to the technical field of particle therapy equipment, and the treatment system comprises an accelerator, an irradiation system, a control system, a patient supporting system and an imaging system. The patient supporting system comprises a containing and fixing device, a two-dimensional translation system, a rotating system and a multi-degree-of-freedom mechanical positioning system, the containing and fixing device is connected with the two-dimensional translation system, the two-dimensional translation system is connected with the rotating system, and the two-dimensional translation system controls the relative position of a patient and a rotating center; the rotating system rotates a patient to an appointed angle of a treatment plan or cooperates with the imaging system to obtain a three-dimensional image of the patient, and the irradiation system irradiates a tumor target area; the use method comprises the following steps: generating a treatment plan by reconstructing a three-dimensional CT image, and completing irradiation at different angles according to the treatment plan. According to the treatment system, multi-angle irradiation on a patient can be realized under the condition that a rotating rack is not used, and the manufacturing period and cost of the particle treatment system can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of particle therapy equipment, and in particular to a multi-angle particle therapy system without a rotating frame and a method for using the system. Background Art

[0002] As an advanced radiotherapy method, particle therapy has attracted much attention due to its advantages of high-precision irradiation of tumor target area and reduction of radiation dose to surrounding healthy tissues. In traditional particle therapy facilities, the rotating gantry is the key equipment to achieve multi-angle particle beam projection, which enables the particle beam to flexibly adjust its direction around the patient, thereby optimizing the dose distribution and improving the treatment effect.

[0003] In the existing invention patent 201710739399.9, patent name "Particle beam medical device and its operation method" and invention patent US15727544, patent name "Particle therapy device including MRI" and other related patents, the disclosed rotating frame structure is complex, costly and occupies a large space, which to a certain extent seriously limits the popularization and construction of particle therapy centers around the world.

[0004] In addition, existing particle therapy systems often require a large rotating gantry and a complex mechanism for changing the beam direction, which not only limits the compact design of the equipment, but also prolongs the treatment time for patients. Therefore, how to reduce the dependence on the rotating mechanism while ensuring the treatment accuracy, and reduce the complexity and cost of the system, has become a key technical issue that needs to be urgently solved in the current particle therapy system. Summary of the invention

[0005] The main purpose of the present application is to provide a multi-angle particle therapy system without a rotating frame and a method of using the same, which can achieve multi-angle particle irradiation of a patient without relying on a rotating frame, and has the advantages of compact structure, light weight, simple maintenance, and low manufacturing cost.

[0006] The technical solutions adopted in this application are as follows: First aspect: A multi-angle particle therapy system without a rotating frame, comprising an accelerator, an irradiation system, a control system, a patient support system and an imaging system, wherein the patient support system comprises a accommodating fixture, a two-dimensional translation system, a rotation system and a multi-degree-of-freedom mechanical positioning system, wherein the accommodating fixture is used to carry and position a patient, and the two-dimensional translation system, the rotation system and the multi-degree-of-freedom mechanical positioning system are used to adjust the position of the accommodating fixture in a treatment room to adjust the body area where the patient's target area is located to the irradiation area of the irradiation system; The control system is used to coordinate each subsystem, so that the high-energy particle beam formed by the accelerator is used to irradiate the body area where the patient's target area is determined by the imaging system at multiple angles through the irradiation system.

[0007] Optionally, the accommodation and fixation device is connected to the two-dimensional translation system, the two-dimensional translation system is connected to the rotation system, and the rotation system is connected to the multi-degree-of-freedom mechanical positioning system.

[0008] Optionally, the accommodation and fixation device includes an outer chamber, an airbag and a negative pressure positioning pad. The airbag is fixed on the inner wall of the outer chamber, and the negative pressure positioning pad is placed between the airbag and the patient.

[0009] Optionally, the outer chamber includes two symmetrical chamber bodies and is connected and locked through a hinge and a knob.

[0010] Optionally, the multi-degree-of-freedom mechanical positioning system includes a base, a six-degree-of-freedom mechanical swing arm structure and a bed board. The six-degree-of-freedom mechanical swing arm structure is fixed in the treatment room through the base, the bed board is connected to the six-degree-of-freedom mechanical swing arm structure, and mounting plates for installing the rotation system are arranged at both ends of the bed board.

[0011] Optionally, the rotation system includes two rotation platforms and two rotation motors. The rotation motors are respectively fixed on the two rotation platforms. The rotation platforms are fixed on the mounting plates of the multi-degree-of-freedom mechanical positioning system and are connected to the two-dimensional translation system.

[0012] Optionally, the two-dimensional translation system includes two two-dimensional translation modules and two translation motors. The translation motors are respectively fixed on the two two-dimensional translation modules. The two-dimensional translation modules are respectively connected to both ends of the accommodation and fixation device through connecting rods.

[0013] Optionally, the imaging system includes an X-ray tube and a flat panel detector, and both the X-ray tube and the flat panel detector are installed in the treatment room.

[0014] Optionally, the particle therapy system is applicable to different types of particle therapy, including but not limited to proton, helium ion, and carbon ion therapy.

[0015] Second aspect: A method of using the multi-angle particle therapy system without a rotating gantry according to the above, includes the following steps: S1: Preset the rotation angle according to the patient's CT and target area information; S2: Guide the patient into the accommodation and fixation device and fix the patient's body position; S3: Start the multi-degree-of-freedom mechanical positioning system to perform preliminary positioning on the patient; S4: Start the two-dimensional translation system and adjust the patient's target area to the rotation center of the rotation system; S5: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to a specified angle; S6: Use the imaging system to obtain two-dimensional projection information of the patient; S7: Perform three-dimensional reconstruction on the two-dimensional projection information, generate and store the three-dimensional CT image of the rotated patient; S8: Repeat steps S5 - S7 for each specified angle; S9: Generate a treatment plan based on the CT images of the patient at multiple angles and output the treatment plan parameters to the control system; S10: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to a specified irradiation angle; S11: The accelerator outputs a beam of corresponding energy according to the treatment plan, and the control system controls the irradiation system to irradiate the patient with the beam. After the irradiation at the current angle is completed, the beam is turned off; S12: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to the next irradiation angle; S13: Repeat steps S11 and S12 until the irradiation of the treatment plan is completed.

[0016] Another usage method of the multi-angle particle treatment system without a rotating gantry according to the above: S1: Preset the rotation angle according to the patient's CT and target area information; S2: Guide the patient into the accommodation fixing device and fix the patient's body position; S3: Start the multi-degree-of-freedom mechanical positioning system to perform preliminary positioning on the patient; S4: Start the two-dimensional translation system and adjust the patient's target area to the rotation center of the rotation system; S5: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to a specified angle; S6: Use the imaging system to obtain two-dimensional projection information of the patient; S7: Perform three-dimensional reconstruction on the two-dimensional projection information to generate the three-dimensional CT image of the rotated patient; S8: Repeat steps S5 - S7 for each specified angle; S9: Generate a treatment plan based on the CT images of the patient at multiple angles and output the treatment plan parameters to the control system; S10: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to a specified irradiation angle; S11: Use the imaging system to obtain the two-dimensional projection information of the patient at the current angle; S12: Reconstruct the three-dimensional CT image of the patient at the current angle in real time based on the two-dimensional projection information at the current angle, compare the three-dimensional CT image reconstructed in real time with the CT image at the current angle used when formulating the treatment plan, and calculate the deviation of the target area position; S13: Based on the deviation of the target area position, determine whether the deviation of the target area position exceeds a preset threshold. If so, pause the treatment; if not, the accelerator outputs a beam of corresponding energy for irradiation treatment according to the treatment plan; S14: Start the rotation system, and rotate the accommodation and fixation device and the two-dimensional translation system to the next irradiation angle; S15: Repeat steps S11 - S14 until the irradiation of the treatment plan is completed.

[0017] Compared with the prior art, the beneficial effects of the present application are as follows: A multi-angle particle therapy system without a rotating gantry proposed in the embodiment of the present application realizes multi-angle irradiation of a patient without using a rotating gantry, and has the advantages of low manufacturing cost, simple maintenance, and light weight. By using two rotating platforms and two two-dimensional translation modules, the relative position of the patient and the rotation center can be adjusted and rotated to the angles specified in the treatment plan, and cooperate with the irradiation system for multi-angle irradiation. In addition, the structure of the particle therapy system is simple, making the equipment layout in the treatment room more compact and reducing the space occupation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional structure schematic diagram of the patient support system (horizontally placed), irradiation system (vertically placed) and imaging system of the present invention in the first usage state; Figure 2 It is a three-dimensional structure schematic diagram of the patient support system (vertically placed), irradiation system (horizontally placed) and imaging system of the present invention in the second usage state; Figure 3 It is a three-dimensional structure schematic diagram of the patient support system (horizontally placed), irradiation system (horizontally placed) and imaging system of the present invention in the third usage state; Figure 4 It is a three-dimensional structure schematic diagram of the central section of the accommodation and fixation device of the present invention; Figure 5 It is a planar structure schematic diagram of the assembly connection of the two-dimensional translation system and the rotation system of the present invention; Figure 6 It is a three-dimensional structure schematic diagram of the assembly connection of the two-dimensional translation system and the rotation system of the present invention; Figure 7 It is a three-dimensional structure schematic diagram of the assembly connection of the two-dimensional translation system and the rotation system of the present invention from another perspective; Figure 8Schematic three-dimensional structure diagram of the assembly connection between the two-dimensional translation system and the connecting rod of the present invention; Figure 9 Schematic three-dimensional structure diagram of the assembly connection between the two-dimensional translation system, the connecting rod and the accommodation and fixing device of the present invention; Figure 10 Schematic three-dimensional structure diagram of the assembly connection between the two-dimensional translation system, the connecting rod and the accommodation and fixing device from another perspective of the present invention; Figure 11 Schematic plan structure diagram of the multi-degree-of-freedom mechanical positioning system of the present invention; Figure 12 Schematic diagram of the system composition of the multi-angle particle therapy system without a rotating gantry provided by the embodiment of the present application; Figure 13 Schematic flow chart of a usage method of the multi-angle particle therapy system without a rotating gantry provided by the embodiment of the present application; Figure 14 Schematic flow chart of another usage method of the multi-angle particle therapy system without a rotating gantry provided by the embodiment of the present application.

[0019] Explanation of the reference numerals in the drawings: 101 - Accelerator, 102 - Irradiation system, 103 - Control system, 104 - Imaging system, 105 - Patient support system, 1 - Accommodation and fixing device, 2 - Two-dimensional translation system, 3 - Rotation system, 4 - Multi-degree-of-freedom mechanical positioning system, 5 - Connecting rod, 11 - Negative pressure positioning pad, 12 - Airbag, 13 - Outer chamber, 14 - Hinge, 15 - Knob, 21 - Two-dimensional translation module, 22 - Translation motor, 31 - Rotation platform, 32 - Rotation motor, 41 - Mounting plate, 42 - Bed plate, 43 - Six-degree-of-freedom mechanical swing arm structure, 44 - Base, 61 - X-ray tube 6, 62 - Flat panel detector, 63 - Conical X-ray beam. Detailed implementation manners

[0020] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present application.

[0021] It should be noted that all the directional indications (such as up, down, left, right, front, back...) in the embodiments of the present application are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0022] In this application, unless otherwise clearly specified and defined, terms such as "connection" and "fixation" shall be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0023] Referring to the attached Figure 12 , an embodiment of the present application provides a multi-angle particle therapy system without a rotating rack, which is applicable to different types of particle therapy, including but not limited to protons, helium ions, and carbon ions. The therapy system is equipped with a treatment room by itself, and the patient completes the irradiation process in the treatment room. Specifically, the therapy system at least includes five subsystems: an accelerator 101, an irradiation system 102, a control system 103, an imaging system 104, and a patient support system 105. The imaging system 104 includes an X-ray tube 61 and a flat panel detector 62. Both the X-ray tube 61 and the flat panel detector 62 are installed in the treatment room. The X-ray tube 61 emits a conical X-ray beam 63 that irradiates the flat panel detector 62 through the patient support system 105. The accelerator 101 is connected to the irradiation system 102. The irradiation system 102, the patient support system 105, and the imaging system 104 are installed in the treatment room. The accelerator 101 is used to accelerate particles to form a high-energy particle beam for irradiation. The high-energy particle beam acts on the patient through the irradiation system 102 to complete the irradiation process. The control system 103 is connected to the irradiation system 102, the patient support system 105, and the imaging system 104 through data interfaces, and cooperates with each subsystem to work.

[0024] It should be noted that in this embodiment, the accelerator 101, the irradiation system 102, and the imaging system 104 can adopt mature components in the existing particle therapy system, and their structural compositions, working principles, and functional uses have no substantial differences from the prior art. The related functions of the control system 103 are also realized based on conventional control principles, but the controlled objects are expanded in this embodiment. In addition to the conventional controlled objects, new control functions for the two-dimensional translation system 2 and the rotation system 3 are added.

[0025] In the above, as Figures 1 to 3 and Figure 12 shown, the patient support system 105 includes a housing and fixation device 1, a two-dimensional translation system 2, a rotation system 3, and a multi-degree-of-freedom mechanical positioning system 4. The housing and fixation device 1 is used to carry and position the patient. The two-dimensional translation system 2, the rotation system 3, and the multi-degree-of-freedom mechanical positioning system 4 are used to adjust the position of the housing and fixation device 1 in the treatment room to adjust the body area where the patient's target area is located to the irradiation area of the irradiation system.

[0026] Specifically, as Figures 1 to 4 shown, the accommodation fixing device 1 is composed of an outer bin 13, an airbag 12, and a negative pressure positioning pad 11. The negative pressure positioning pad 11 is placed between the airbag 12 and the patient. The airbag 12 is fixed to the inner wall of the outer bin 13. The airbag 12 can adjust its thickness by repeatedly inflating and deflating. The outer bin 13 is divided into two symmetrical bin bodies. The bin bodies are not limited to being made of polycarbonate. And the two bin bodies are connected and locked by a hinge 14 and a knob 15. The hinge 14 and the knob 15 can be made of zirconia toughened ceramics or polycarbonate. It can be understood that ceramics have extremely high hardness and wear resistance, and polycarbonate has advantages in mechanical strength such as good toughness and good impact resistance. And choosing non-metallic materials can avoid metal artifacts during imaging.

[0027] Meanwhile, as Figures 5 to 10 shown, the two-dimensional translation system 2 includes two groups of two-dimensional translation modules 21 and two translation motors 22. The translation motors 22 are respectively installed on the two groups of two-dimensional translation modules 21. Both ends of the outer bin 13 are connected to the two-dimensional translation modules 21 through connecting rods 5. The two-dimensional translation modules 21 are installed on the rotation system 3. In this embodiment, the two-dimensional translation module is a high-precision electric translation stage. After connecting both ends of the outer bin 13 to the two-dimensional translation modules 21, by using the movement of the two-dimensional translation modules 21, the outer bin 13 is driven to move in a direction perpendicular to the axis of the outer bin 13, so as to adjust the relative position between the patient's target area and the rotation center of the rotation system 3.

[0028] It should be noted here that, as Figure 9 and Figure 10 shown, a frustum-shaped connecting seat is connected to one end of the connecting rod 5 and the outer bin 13. The connecting seat is fixedly connected to the lower part of the outer bin 13, while the upper part of the connecting seat and the outer bin 13 are in a non-fixed connection state (it can be understood that the upper half has an arc-shaped hole structure that is not connected to the connecting seat), so that the outer bin 13 can be opened.

[0029] It is easy to understand that the connecting rod 5, as a transmission connection component between the accommodation fixing device 1 and the two-dimensional translation module 21, one end of it is fixedly connected to the lower structure (i.e., the outer bin 13) of the accommodation fixing device 1 through a frustum-shaped connecting seat, and the other end is connected to the slider structure of the two-dimensional translation module 21. When the two-dimensional translation module 21 moves, the accommodation fixing device 1 can be driven to achieve synchronous translation in a plane perpendicular to the axis of the outer bin 13 through the connecting rod 5.

[0030] Of course, it also needs to be emphasized that: the movement of the accommodation fixing device 1 in the plane depends on the two-dimensional translation module 21 configured in the system. The plane in which the two-dimensional translation module 21 moves can be defined as the XY plane. The two-dimensional translation module 21 is an existing mature high-precision electric slide table assembly, usually adopting a cross-overlapping structure, which can be seen in Figures 5 to 10As shown, the two-dimensional translation module includes two sets of linear guide rail motion mechanisms arranged perpendicular to each other. Conventionally, each set of linear guide rail motion mechanisms includes a linear guide rail, a slider, an electric motor, and a transmission mechanism. The transmission mechanism is used to convert the rotational motion of the electric motor into the linear motion of the slider along the direction of the linear guide rail. Common types of transmission mechanisms include synchronous belt mechanisms or ball screw mechanisms. Taking one set of horizontally placed linear guide rail motion mechanisms as an example, when the corresponding electric motor is started, the electric motor rotates to drive the connected transmission mechanism to operate. The transmission mechanism converts the rotational motion into the linear motion of the slider along the guide rail direction, thereby driving the connecting structure (such as a holding and fixing device) to move horizontally. If it is necessary to achieve the movement of the slider in the vertical direction, it is necessary to start the electric motor corresponding to the vertically placed linear guide rail motion mechanism, which drives the corresponding transmission mechanism to drive the slider to move vertically. Among them, one set of guide rails of the two-dimensional translation module 21 is fixedly installed on the other set of sliders to achieve independent motion control in the X-axis and Y-axis directions.

[0031] In this embodiment, the two two-dimensional translation modules 21 are respectively located at both ends of the holding and fixing device 1 and are connected to the holding and fixing device 1 through a connecting rod 5. The control system 103 drives the two two-dimensional translation modules 21 to move on the X-axis and Y-axis respectively, so as to realize the synchronous movement of the holding and fixing device 1 in the plane perpendicular to the rotation axis (i.e., the XY plane).

[0032] As mentioned above, such as Figures 1 to 3 and Figures 5 to 9 As shown, the rotation system 3 includes two rotating platforms 31 and two rotating motors 32. The rotating motors 32 are respectively installed on the two rotating platforms 31. The rotating motors 32 are used to drive the rotating platforms 31 to rotate. The two-dimensional translation module 21 is installed on the rotating platform 31 to realize the rotation of the two-dimensional translation module 21 and the outer chamber 13 together. At the same time, combined with Figure 11 As shown, the multi-degree-of-freedom mechanical positioning system 4 includes a base 44, a six-degree-of-freedom mechanical swing arm structure 43, and a bed board 42 with mounting plates 41 at both ends. The rotating platform 31 is installed on the mounting plate 41. The bed board 42 is connected to the six-degree-of-freedom mechanical swing arm structure 43. The six-degree-of-freedom mechanical swing arm structure 43 is installed on the base 44. The base 44 is fixed in the treatment room.

[0033] Conceivably, the workflow of the accommodation fixture during use is as follows: Open the outer chamber 13, lay the negative pressure positioning pad 11 on the surface of the airbag 12, guide the patient into the accommodation fixture 1, adjust the thickness of the airbag 12 and perform an air extraction operation on the negative pressure positioning pad 11 to make the negative pressure positioning pad 11 tightly adsorb to the patient's body surface, complete the patient's body position fixation, and rotate the knob 15 to lock the hatch of the outer chamber 13; The two-dimensional translation module 21 controls the accommodation fixture 1 to move within a plane perpendicular to the axis of the outer chamber 13 to adjust the patient's target area to the rotation center; Start the rotating platform 31 to drive the accommodation fixture 1 and the two-dimensional translation system 2 to rotate to a specified angle. It can be understood that the rotating platform 31 is a turntable structure well-known in the art.

[0034] It should be noted that: In the above embodiment, the two-dimensional translation module 21 is fixedly installed on the rotating platform 31 to form an integrated and linked rotating structure. The connection method between the two-dimensional translation module 21 and the rotating platform 31 can be a detachable connection or an indirect connection, specifically including but not limited to the following forms: For example, directly fixed by bolts, or indirectly connected by using intermediate connection members (such as flange plates, connecting plates, etc.).

[0035] The rotating platform 31 is driven by a rotating motor to rotate around its own central axis. Since the two-dimensional translation module 21 is fixedly installed on the rotating platform 31, when the rotating platform 31 rotates, the two-dimensional translation module 21 also rotates synchronously as a part of its overall structure, thereby driving the accommodation fixture 1 connected to it to rotate.

[0036] In this embodiment, the patient support system 105 can be selected to be placed horizontally or vertically. For details, refer to Figure 1 and Figure 2 , Different placement methods are adapted to different treatment use scenarios, improving the versatility and flexibility of the system. And the patient support system 105 can be respectively used in combination with the vertical fixed beam irradiation method and the horizontal fixed beam irradiation method in the horizontal placement state. For details, refer to Figure 1 and Figure 3 It should be noted that the placement method of the patient support system 105 does not affect the specific usage method of the particle therapy system.

[0037] In the above embodiment, it should be emphasized that: The rotation system 3 includes two rotating platforms 31. The rotational movement of the patient support system 105 is a rotation around the axis formed by the rotation center connecting the two rotating platforms 31. That is, the rotation axis of the patient support system 105 is an axis determined by the composition of the rotating platform 31, and the specific direction is determined according to the actual layout method. As Figure 1 shown, when the patient support system 105 is placed horizontally, this rotation axis is parallel to the floor of the treatment room; As Figure 2As shown, when the patient support system 105 is placed vertically, the axis of rotation is perpendicular to the floor of the treatment room.

[0038] For ease of explanation, taking the case where the patient support system 105 is placed horizontally as an example, the present embodiment also provides a method of using a multi-angle particle therapy system without a rotating gantry, as Figure 13 shown, and the specific implementation steps are as follows: S1: Preset the rotation angle according to the patient's CT and target area information; S2: Guide the patient into the accommodation fixing device, and fix the patient's body position through the airbag and the negative pressure positioning pad; S3: Start the multi-degree-of-freedom mechanical positioning system to perform preliminary positioning on the patient; S4: Start the two-dimensional translation system to adjust the patient's target area to the rotation center; S5: Start the rotation system to rotate the accommodation fixing device and the two-dimensional translation system to the specified angle; S6: The X-ray tube emits a conical X-ray beam, and the flat panel detector collects the two-dimensional projection information after the X-ray beam penetrates the human body; S7: Perform three-dimensional reconstruction on the two-dimensional projection information to generate and store the three-dimensional CT image of the patient after rotation; S8: Repeat steps S5 - S7 for each specified angle; S9: Generate a treatment plan based on the CT images of the patient at multiple angles, and output the treatment plan parameters to the control system; S10: Start the rotation system to rotate the accommodation fixing device and the two-dimensional translation system to the specified irradiation angle; S11: The accelerator outputs a beam of corresponding energy according to the treatment plan, and the control system controls the irradiation system to perform beam irradiation on the patient. After the irradiation at the current angle is completed, the beam is turned off; S12: Start the rotation system to rotate the accommodation fixing device and the two-dimensional translation system to the next irradiation angle; S13: Repeat steps S11 and S12 until the irradiation of the treatment plan is completed.

[0039] Furthermore, to verify whether the target area displacement caused by the patient's rotation during the irradiation process meets the expectations, the embodiment of the present application also provides another method of using a multi-angle particle therapy system without a rotating gantry, as Figure 14 shown, and the specific implementation steps are as follows: S1: Preset the rotation angle according to the patient's CT and target area information; S2: Guide the patient into the accommodation fixing device, and fix the patient's body position through the airbag and the negative pressure positioning pad; S3: Start the multi-degree-of-freedom mechanical positioning system to perform preliminary positioning on the patient; S4: Start the two-dimensional translation system and adjust the patient's target area to the rotation center; S5: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to a specified angle; S6: The X-ray tube emits a conical X-ray beam, and the flat panel detector collects the two-dimensional projection information after the X-ray beam penetrates the human body; S7: Perform three-dimensional reconstruction on the two-dimensional projection information to generate and store the three-dimensional CT image of the patient after rotation; S8: Repeat steps S5 - S7 for each specified angle; S9: Generate a treatment plan based on the CT images of the patient at multiple angles and output the treatment plan parameters to the control system; S10: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to the specified irradiation angle; S11: Use the imaging system to obtain the two-dimensional projection information of the patient at the current angle; S12: Based on the two-dimensional projection information at the current angle, reconstruct the three-dimensional CT image of the patient at the current angle in real time, compare it with the CT image at this angle used when formulating the treatment plan, and calculate the target area position deviation; S13: Based on the target area position deviation, determine whether the target area position deviation exceeds the preset threshold. If so, pause the treatment; if not, the accelerator outputs a beam of corresponding energy for irradiation treatment according to the treatment plan; S14: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to the next irradiation angle; S15: Repeat steps S11 - S14 until the irradiation of the treatment plan ends.

[0040] In this embodiment, the preliminary positioning in step S3 refers to aligning the rotation center of the rotation system 3 with the irradiation center of the irradiation system 102 and the imaging center of the imaging system 104, and adjusting the body area where the patient's target area is located to the irradiation area of the irradiation system 102.

[0041] In this embodiment, in the described usage method, the relevant steps of reconstructing the three-dimensional CT image of the patient through the two-dimensional projection information penetrated by the X-ray and generating a treatment plan based on the multi-angle CT images are as follows. The specific implementation principle is as follows: First, the two-dimensional projection information penetrated by the X-ray is reconstructed into a three-dimensional CT image through an image reconstruction algorithm (see non-patent literature: ①Zhang Y, Hu D, Li W, et al. 2V-CBCT: Two-orthogonal-projection based CBCT reconstruction and dose calculation from real CBCT projection data[J]. International Journal of Radiation Oncology, Biology, Physics, 2023, 117(2): e748.); then, a certain angle is selected as the reference phase in each angle CT image, and a unified anatomical coordinate system is constructed according to the reference phase; subsequently, referring to the preset rotation angle, a unique beam irradiation direction is specified for each phase CT and the dose influence matrix is calculated; then, a non-rigid registration algorithm (see non-patent literature: ①Dong J, Lu K, Xue J, et al. Accelerated nonrigid image registration using improved Levenberg–Marquardt method[J]. Information Sciences, 2018, 423: 66-79) is used to establish a deformation field between each phase CT and the reference phase CT; based on the deformation field, the dose influence matrix calculated on each phase CT is mapped to the reference phase CT, so as to superimpose the dose influence matrices of each phase CT under the unified anatomical structure; finally, a beam weight optimization algorithm based on a multi-objective optimization model is constructed (see non-patent literature: ①Watkins WT, Nourzadeh H, Siebers JV. Multiobjective, Multidelivery Optimization for Radiation Therapy Treatment Planning. Adv Radiat Oncol. 2019 Sep 27;5(2):279-288. doi: 10.1016 / j.adro.2019.09.003. PMID: 32280828; PMCID: PMC7136667.), solve the weight coefficients of the beam currents at each irradiation angle to obtain the optimized beam current weight coefficients, and generate a treatment plan that meets the clinical dosimetry and biological evaluation criteria.

[0042] It should be noted that the relevant algorithm for reconstructing the patient's three-dimensional CT image based on the two-dimensional projection information of the X-ray penetrating the patient can be integrated into each system as a functional module or set up as an independent image reconstruction system; the process of generating a treatment plan based on multi-angle CT images can be completed by the treatment planning system.

[0043] Furthermore, to improve the uniformity and robustness of the dose distribution during actual irradiation, when irradiating the patient with beam currents at each angle according to the treatment plan, a repeated scanning irradiation strategy can be adopted. Divide the planned dose at each irradiation angle into multiple sub-parts, and rotate the patient to this angle multiple times for repeated irradiation, and only transfer a part of the dose each time. Through repeated scanning irradiation, the dose distribution deviation caused by target movement or system error can be effectively balanced, thereby improving the irradiation accuracy and treatment effect.

[0044] In this embodiment, the number of X-ray tubes 61 and flat panel detectors 62 can be flexibly configured according to requirements. When multiple groups of X-ray tubes 61 and flat panel detectors 62 are arranged, they can be fixed in the treatment room in an orthogonal or specific angle combination; the repeat positioning accuracy of the two-dimensional translation module 21 is ±0.1 mm, and the angular resolution of the rotary platform 31 is 0.1°; the types of beam particles that the irradiation system 102 can adapt to include but are not limited to various ion beams such as protons, helium ions, and carbon ions.

[0045] In summary, a multi-angle particle therapy system without a rotating gantry provided by the present invention has the main advantages of simplified structure, low manufacturing cost, reliable performance, strong operation flexibility, and simple maintenance. The present invention abandons the complex rotating gantry structure in the traditional particle therapy system, significantly reduces the equipment volume and weight of the therapy system, and reduces the space requirement. This not only makes the layout of the treatment room more compact, but also reduces the manufacturing and maintenance costs of the system. At the same time, it also reduces the mechanical complexity and potential failure rate of the system. In addition, this system realizes the rotation around the patient's target area, ensures that the particle beam always irradiates around the target area, thereby accurately concentrating the treatment dose on the target area and reducing the total treatment time during multi-angle irradiation.

[0046] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A multi-angle particle therapy system without a rotating gantry, comprising an accelerator, an irradiation system, a control system, a patient support system and an imaging system, characterized in that: The patient support system includes a housing fixing device, a two-dimensional translation system, a rotation system, and a multi-degree-of-freedom mechanical positioning system. The housing fixing device is used to carry and position the patient, and the two-dimensional translation system, rotation system, and multi-degree-of-freedom mechanical positioning system are used to adjust the position of the housing fixing device in the treatment room so as to adjust the body area where the patient's target area is located to the irradiation area of the irradiation system. The control system is used to coordinate each subsystem so that the high-energy particle beam formed by accelerating through the accelerator irradiates the body area where the patient's target area is determined by the imaging system from multiple angles through the irradiation system.

2. The multi-angle particle therapy system without a rotating gantry according to claim 1, wherein The housing fixing device is connected to the two-dimensional translation system, the two-dimensional translation system is connected to the rotation system, the rotation system is connected to the multi-degree-of-freedom mechanical positioning system, and the multi-degree-of-freedom mechanical positioning system and the imaging system are installed in the treatment room.

3. The multi-angle particle therapy system without a rotating gantry according to claim 1, wherein The housing fixing device includes an outer chamber, an airbag, and a negative pressure positioning pad. The airbag is fixed on the inner wall of the outer chamber, and the negative pressure positioning pad is placed between the airbag and the patient.

4. The multi-angle particle therapy system without a rotating gantry according to claim 3, wherein The outer chamber includes two symmetrical chamber bodies and is linked and locked through a hinge and a knob.

5. The multi-angle particle therapy system without a rotating gantry according to claim 1, characterized in that The multi-degree-of-freedom mechanical positioning system includes a base, a six-degree-of-freedom mechanical swing arm structure, and a bed board. The six-degree-of-freedom mechanical swing arm structure is fixed in the treatment room through the base. The bed board is connected to the six-degree-of-freedom mechanical swing arm structure, and mounting plates for installing the rotation system are provided at both ends of the bed board.

6. The multi-angle particle therapy system without a rotating gantry according to claim 5, wherein the rotation system includes two rotating platforms and two rotating motors. The rotating motors are respectively fixed on the two rotating platforms. The rotating platforms are fixed on the mounting plates of the multi-degree-of-freedom mechanical positioning system and are connected to the two-dimensional translation system.

7. The multi-angle particle therapy system without a rotating gantry according to claim 1, characterized in that, The two-dimensional translation system includes two two-dimensional translation modules and two translation motors. The translation motors are respectively fixed on the two two-dimensional translation modules. The two-dimensional translation modules are respectively connected to both ends of the housing fixing device through connecting rods.

8. The multi-angle particle therapy system without a rotating gantry according to claim 1, characterized in that The imaging system includes an X-ray tube and a flat panel detector. Both the X-ray tube and the flat panel detector are installed in the treatment room.

9. The multi-angle particle therapy system without a rotating gantry according to claim 1, characterized in that The particle therapy system is applicable to different types of particle therapy, including but not limited to proton, helium ion, and carbon ion therapy.

10. A method of using a multi-angle particle therapy system without a rotating gantry according to any one of claims 1-9, characterized in that, Including the following steps: S1: Preset the rotation angle according to the patient's CT and target area information. S2: Guide the patient into the housing fixing device and fix the patient's body position. S3: Start the multi-degree-of-freedom mechanical positioning system to perform a preliminary positioning of the patient. S4: Start the two-dimensional translation system to adjust the patient's target area to the rotation center of the rotation system. S5: Start the rotation system to rotate the housing fixing device and the two-dimensional translation system to the specified angle. S6: Use the imaging system to obtain the two-dimensional projection information of the patient. S7: Perform three-dimensional reconstruction on the two-dimensional projection information to generate and store the three-dimensional CT image of the rotated patient. S8: Repeat steps S5-S7 for each specified angle. S9: Generate a treatment plan based on the patient's multi-angle CT images and output the treatment plan parameters to the control system. S10: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to the specified irradiation angle; S11: The accelerator outputs a beam of corresponding energy according to the treatment plan. The control system controls the irradiation system to irradiate the patient with the beam. After the irradiation at the current angle is completed, the beam is turned off; S12: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to the next irradiation angle; S13: Repeat steps S11 and S12 until the irradiation of the treatment plan ends.

11. Another method of using the multi-angle particle therapy system without a rotating gantry according to any one of claims 1-9, characterized in that, It includes the following steps: S1: Preset the rotation angle according to the patient's CT and target area information; S2: Guide the patient into the accommodation fixing device and fix the patient's body position; S3: Start the multi-degree-of-freedom mechanical positioning system to perform preliminary positioning on the patient; S4: Start the two-dimensional translation system and adjust the patient's target area to the rotation center of the rotation system; S5: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to the specified angle; S6: Use the imaging system to obtain the two-dimensional projection information of the patient; S7: Perform three-dimensional reconstruction on the two-dimensional projection information to generate a three-dimensional CT image of the patient after rotation; S8: Repeat steps S5 - S7 for each specified angle; S9: Generate a treatment plan based on the CT images of the patient at multiple angles and output the treatment plan parameters to the control system; S10: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to the specified irradiation angle; S11: Use the imaging system to obtain the two-dimensional projection information of the patient at the current angle; S12: Based on the two-dimensional projection information at the current angle, reconstruct the three-dimensional CT image of the patient at the current angle in real time and compare the real-time reconstructed three-dimensional CT image with the CT image at the current angle used when formulating the treatment plan, and calculate the target area position deviation; S13: Based on the target area position deviation, determine whether the target area position deviation exceeds the preset threshold. If so, suspend the treatment; if not, the accelerator outputs a beam of corresponding energy according to the treatment plan for irradiation treatment; S14: Start the rotation system and rotate the accommodation fixing device and the two-dimensional translation system to the next irradiation angle; S15: Repeat steps S11 - S14 until the irradiation of the treatment plan ends.

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