Radiotherapy device and control method therefor

Abstract

Disclosed in the present application are a radiotherapy device and a control method therefor. The device comprises a fixed base, a rotating frame, a treatment beam assembly, and a fan beam CT assembly. The rotating frame is rotatably arranged on the fixed base. The treatment beam assembly and the fan beam CT assembly are arranged on the rotating frame. A rotation plane where the axis of a treatment beam of an accelerator treatment head is located is coplanar with a rotation plane where the axis of a diagnostic beam of the fan beam CT assembly is located, and the axis of the treatment beam and the axis of the diagnostic beam intersect at the rotation axis of the rotating frame. By means of the rotating frame, the treatment beam assembly and the fan beam CT assembly can be driven at the same time. Both radiotherapy and CT imaging can be realized, and during CT imaging and radiotherapy switching, a patient does not need to be displaced, thereby improving the accuracy of imaging and treatment. When a treatment working state is switched to a diagnostic working state, the treatment beam assembly is controlled to return to a preset position, so that the device that rotates at a high speed is in a dynamic balance state, thereby protecting the overall device.

Description

Radiotherapy device and control method thereof

[0001] Cross-reference to related applications

[0002] This application claims priority to the Chinese patent application No. 202410823506.6, filed on June 25, 2024, and entitled “Radiotherapy device and control method thereof”, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to a radiotherapy device, in particular to a radiotherapy device with a fan-beam CT assembly. The present application also relates to a control method of the radiotherapy device. BACKGROUND

[0004] Image guidance plays an extremely important role in patient positioning and adaptive radiotherapy of radiotherapy, making the radiotherapy positioning process visible and accurate, and developing towards a clearer and more accurate direction. Various manufacturers have successively launched products based on image guidance, such as ultrasound, cone beam computed tomography (CBCT), magnetic resonance, and even positron emission computed tomography (PET) guided products, to achieve more excellent anatomical structure imaging, soft tissue imaging or biological function imaging, in order to improve the treatment accuracy. These technologies have achieved the acquisition of patient volume images before and during treatment, and have realized the imaging and positioning of tumors, normal tissues or patient surface contours, the accurate three-dimensional positioning of anatomical structures during the positioning process, and the adjustment of position or plan according to the position change.

[0005] And in order to further ensure the accuracy of the image guided position and avoid image errors caused by patient movement, the prior art also has a technical solution of integrating the image guidance device and the radiotherapy device into one. However, in the above-mentioned prior art of image guidance, due to the limitation of technical principles, it is difficult to meet the requirements of adaptive radiotherapy for soft tissue resolution, CT value linearity, uniformity, accuracy and other indicators, becoming one of the bottlenecks of automatic delineation and dose calculation in the adaptive radiotherapy process.

[0006] The traditional fan-beam CT which can also realize image guidance is a gold standard level image technology in the radiotherapy department, and has a high cost performance in consideration of the above requirements. However, the fan-beam CT needs to rotate continuously at a high speed to realize imaging, and has a large space occupation and a large weight. Generally, the rotation speed of the radiotherapy device during radiotherapy is not more than 4 RPM, while the CT imaging is generally at 30 RPM to 80 RPM. Therefore, when the two are combined together, the stability and safety of the radiotherapy device in the high-speed state need to be considered, and it is difficult to integrate the radiotherapy device, which is a technical blank in the prior art.

[0007] Application content

[0008] In view of the above problems, the present application discloses a radiotherapy device and a control method thereof, which ingeniously integrates a fan-beam CT in the radiotherapy device, realizes radiotherapy and CT imaging at the same time through a rotating frame, and can provide high-precision image guidance without large-scale displacement of the patient.

[0009] The present application also discloses a control method of the above radiotherapy device.

[0010] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0011] The present application provides a radiotherapy device, which comprises a fixed seat, a rotating frame, a treatment beam assembly and a fan-beam CT assembly. The rotating frame is rotatably arranged on the fixed seat. The treatment beam assembly and the fan-beam CT assembly are arranged on the rotating frame. The rotating plane of the axis of the treatment beam of the accelerator treatment head and the rotating plane of the axis of the diagnostic beam of the fan-beam CT assembly are coplanar, and the axis of the treatment beam and the axis of the diagnostic beam intersect at the rotating shaft of the rotating frame. The treatment beam assembly comprises an accelerator treatment head, a pulse modulator, a magnetron and a treatment beam imaging unit arranged opposite to the accelerator treatment head. The fan-beam CT assembly comprises a fan-beam CT tube and a diagnostic beam detection unit arranged opposite to the fan-beam CT tube. The axis of the treatment beam and the axis of the diagnostic beam are perpendicular to each other and coplanar. The pulse modulator is arranged between the accelerator treatment head and the diagnostic beam detection unit, and the pulse unit of the pulse modulator is arranged in the radial direction of the rotating shaft. The magnetron is arranged between the accelerator treatment head and the fan-beam CT tube, and the magnetron is arranged in the radial direction of the rotating shaft.

[0012] In a schematic embodiment of the radiotherapy device, the radiotherapy device further comprises a water cooling device, a water distributor, a water inlet pipe and a water return pipe. The water cooling device is arranged on the rotating frame and is arranged on the outer side of the treatment beam imaging unit in the radial direction of the rotating shaft. The water distributor is arranged on the rotating frame and is arranged between the accelerator treatment head and the fan-beam CT tube to provide cooling water for the heat generating device of the accelerator. The water inlet pipe and the water return pipe are connected between the water cooling device and the water distributor, and the water inlet pipe and the water return pipe are arc-shaped pipes with the center at the rotating shaft.

[0013] In an illustrative embodiment of the radiotherapy device, the water cooling device comprises a water cooling pipe and an expansion tank, the water cooling pipe is arranged along the tangential direction of the rotation of the gantry. The expansion tank is arranged parallel to the rotation axis and is connected with the water cooling pipe.

[0014] In an illustrative embodiment of the radiotherapy device, the radiotherapy device further comprises a shielding body, the shielding body is movably arranged on the radially inner side of the diagnostic beam detection unit, and has a shielding position capable of shielding the diagnostic beam detection unit when the accelerator treatment head is working, and an opening position capable of exposing the diagnostic beam detection unit when the fan-beam CT tube is working; the thickness of the shielding body is stepwise reduced from one end close to the treatment beam imaging unit.

[0015] In an illustrative embodiment of the radiotherapy device, the accelerator treatment head comprises an acceleration tube, a fixing plate is arranged on the gantry, the fixing plate is provided with a through hole for the acceleration tube to pass through; the fixing plate is provided with a fixing ring protruding along the outer edge of the through hole and an adjusting ring embedded in the inside of the fixing ring and concentric with the fixing ring; the acceleration tube passes through the fixing ring and the adjusting ring and is connected with the adjusting ring through a mounting arm; the fixing ring is provided with two pairs of jacks, the two pairs of jacks respectively pass through the fixing ring and abut against the outer sidewall of the adjusting ring in an adjustable manner to realize the position adjustment of the acceleration tube in the horizontal direction; the mounting arm comprises at least three cantilever arms, the connecting ring formed by one end of the three cantilever arms is nested on the outside of the acceleration tube, and the other end of the three cantilever arms is arranged on the adjusting ring; each cantilever arm is adjustably connected with the adjusting ring through a bolt assembly to realize the position adjustment of the acceleration tube in the vertical direction; the bolt assembly comprises at least a vertical adjusting bolt and a fixing bolt penetrating the inside of the vertical adjusting bolt and screwing with the adjusting ring; the two ends of the vertical adjusting bolt are respectively provided with a gasket, and the outside of the vertical adjusting bolt is sleeved with a spring.

[0016] In an illustrative embodiment of the radiotherapy device, the radiotherapy device further comprises:

[0017] A first driving device, the first driving device is used for driving the rotation of the gantry;

[0018] The first driving device comprises a rotor and a stator;

[0019] The rotor is annular and is used for driving the rotation of the gantry; the rotor is provided with a plurality of magnets; the plurality of magnets are uniformly arranged along the circumferential direction of the rotor;

[0020] The stator is annular, is sleeved on the outside of the rotor, and is fixedly connected with the fixed base; the stator is provided with a plurality of groups of coils, and the plurality of groups of coils are uniformly arranged along the circumferential direction of the stator.

[0021] The application also provides a control method of a radiotherapy device, the control method comprising: controlling the radiotherapy device to enter a treatment working state, in the treatment working state, controlling a rotating frame to drive a treatment beam assembly to move to a treatment position to implement radiotherapy; controlling the radiotherapy device to enter a diagnosis working state, in the diagnosis working state, controlling the rotating frame to drive a fan-beam CT assembly to continuously rotate to implement diagnosis imaging. The control method further comprises: before switching from the treatment working state to the diagnosis working state, controlling the treatment beam assembly to return to a preset position; after switching to the diagnosis working state, detecting whether the treatment beam assembly deviates from the preset position, and if it is detected that the treatment beam assembly deviates from the preset position, controlling the rotating frame to reduce speed and enter a low-speed protection state.

[0022] In an illustrative embodiment of the control method of the radiotherapy device, the step of controlling the rotating frame to enter the low-speed protection state further comprises: detecting force allowable values of each component arranged on the rotating frame in a rotating tangential direction; obtaining an acceleration allowable value of the rotating frame according to the minimum force allowable value; obtaining a maximum deceleration curve of the rotating frame according to the acceleration allowable value; and controlling the rotating frame to reduce speed according to the maximum deceleration curve and enter the low-speed protection state.

[0023] In an illustrative embodiment of the control method of the radiotherapy device, the control method further comprises: before entering the treatment working state or the diagnosis working state, performing online monitoring to determine that an axis of a treatment beam and an axis of a diagnosis beam intersect at a rotating shaft of the rotating frame.

[0024] In an illustrative embodiment of the control method of the radiotherapy device, the online monitoring comprises:

[0025] installing a phantom to be tested at a fixed position of a treatment bed and moving a center of the phantom to a mechanically calibrated center position; controlling the treatment bed to move in different directions for multiple times, and performing imaging by the treatment beam assembly after each movement; controlling the treatment beam assembly to perform EPID image acquisition on the phantom, registering the center of the phantom to a center position of an image in the EPID image, and obtaining a registration result of the phantom; controlling the treatment beam assembly to perform Winston-lutz test on the phantom, and obtaining a consistency result of a radiation center of the treatment beam and the mechanically calibrated center position by combining the registration result, and adjusting the treatment beam assembly; and controlling the fan-beam CT assembly to perform CT imaging on the phantom, and obtaining a consistency result of an imaging center of the diagnosis beam and the mechanically calibrated center position, and adjusting the fan-beam CT assembly.

[0026] In an exemplary embodiment of the control method of the radiotherapy device, the control of the fan-beam CT assembly to perform CT imaging on the phantom, the analysis of the consistency of the imaging center of the diagnostic beam with the mechanical center position, further comprises: moving the phantom center to the mechanical center position again, controlling the fan-beam CT assembly to perform image-guided on the phantom, and analyzing the projection coordinate value of the image center position of the phantom in the EPID coordinate system through the EPID image acquisition; and correcting the deviation between the projection coordinate value of the image center position and the EPID mechanical center coordinate value through the adjustment of the CT assembly.

[0027] In an exemplary embodiment of the control method of the radiotherapy device, the radiotherapy device further comprises a plurality of vibration sensors, and the control method further comprises: when the vibration data detected by one vibration sensor exceeds a first preset vibration threshold, controlling the gantry to enter a low-speed protection state.

[0028] In an exemplary embodiment of the control method of the radiotherapy device, the radiotherapy device comprises at least four counterweight devices corresponding to the vibration sensors, each of the counterweight devices comprises a second driving device and a counterweight structure movable by the second driving device,

[0029] The control method further comprises: after the low-speed protection state is entered due to the vibration data of the vibration sensor exceeding the first preset vibration threshold, adjusting the counterweight position of the counterweight structure in the counterweight device corresponding to the vibration sensor according to the vibration sensor from which the vibration data is sent.

[0030] In an exemplary embodiment of the control method of the radiotherapy device, the control method further comprises: when the vibration data detected by the vibration sensor exceeds a second preset vibration threshold, controlling all power supplies of the radiotherapy device except the gantry to be disconnected, and gradually reducing the speed of the gantry to enter a low-speed protection state until the power is turned off after a specific rotating speed.

[0031] In an exemplary embodiment of the control method of the radiotherapy device, the accelerator treatment head of the radiotherapy device comprises a multi-leaf collimator, and the step of controlling the treatment beam assembly to return to the preset position further comprises: returning the multi-leaf collimator, so that the moving direction of the leaf of the multi-leaf collimator is parallel to the rotating shaft of the gantry.

[0032] In an exemplary embodiment of the control method of the radiotherapy device, the multi-leaf collimator comprises a pair of leaf moving frames, and the pair of leaf moving frames can move relative to each other and carry the leaf. The step of controlling the treatment beam assembly to return to the preset position further comprises: returning the leaf moving frame of the multi-leaf collimator, so that the pair of leaf moving frames return to a symmetrical position relative to each other.

[0033] In an illustrative embodiment of the control method of the radiotherapy device, the treatment beam assembly of the radiotherapy device comprises a pair of field diaphragms, and the step of returning the treatment beam assembly to the preset position further comprises: returning the field diaphragms to symmetrical positions.

[0034] In an illustrative embodiment of the control method of the radiotherapy device, the radiotherapy device further comprises a water cooling device for maintaining a constant temperature of the accelerator heat generating components, and before switching from the treatment working state to the diagnosis working state, the water supply amount of the water cooling device is reduced to a preset supply value.

[0035] In an illustrative embodiment of the control method of the radiotherapy device, the radiotherapy device further comprises a fan arranged on the rotating frame, and before switching from the treatment working state to the diagnosis working state, the rotating speed of the fan is reduced to a preset rotating speed value.

[0036] From the above, the at least one technical solution adopted by the embodiments of the present application can achieve the following beneficial effects: on the one hand, the rotating frame can drive the treatment beam assembly and the fan-shaped beam CT assembly at the same time, which can realize both radiotherapy and CT imaging, and the patient does not need to be moved when switching between CT imaging and radiotherapy, so that the centers of treatment and imaging are converged at one place, the positioning is accurate, and there is no need to consider traditional displacement compensation during treatment, so that the treatment plan based on CT imaging is more accurate; on the other hand, when switching from the treatment working state to the diagnosis working state, the treatment beam assembly is returned to the preset position, which can protect the components of the treatment beam assembly from being damaged due to high-speed rotation, and can also make the high-speed rotating device in a dynamic balance state, thereby protecting the whole device, so that the whole device can achieve a high rotating speed of 80 RPM for CT imaging; on the other hand, since the radiotherapy device integrates the treatment beam assembly and the fan-shaped beam CT assembly, after the patient completes CT diagnosis, the radiotherapy plan can be directly implemented without other preparation processes, thereby simplifying the implementation steps and improving and optimizing the treatment process. BRIEF DESCRIPTION OF DRAWINGS

[0037] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of preferred embodiments, and are not meant to limit the scope of the present application. Moreover, the same reference numerals in different figures represent the same or similar components. In the drawings:

[0038] FIG. 1 is a perspective view illustrating an illustrative embodiment of a radiotherapy device.

[0039] FIG. 2 is a perspective view illustrating another illustrative embodiment of a radiotherapy device.

[0040] Fig. 3 is a schematic diagram illustrating an exemplary embodiment of a water cooling system of the radiation therapy device.

[0041] Fig. 4 is a flowchart illustrating specific control steps before switching from a treatment operation mode to a diagnostic operation mode.

[0042] Fig. 5 is a schematic diagram illustrating a structure of an exemplary embodiment of a multi-leaf collimator.

[0043] Fig. 6 is a flowchart illustrating steps of controlling the gantry into a low-speed protection mode.

[0044] Fig. 7 is a schematic diagram illustrating an arrangement of a vibration sensor and a counterweight device.

[0045] Fig. 8 is a schematic diagram illustrating a structure of a fixing ring and an adjusting ring of the radiation therapy device.

[0046] Fig. 9 is a schematic diagram illustrating a structure of a first driving device of the radiation therapy device.

[0047] Reference Signs: 10 fixing base 20 gantry 21 fixing plate 22 rotating shaft 23 fixing ring 24 adjusting ring 25 jackscrew 26 mounting arm 27 bolt assembly 271 vertical adjusting bolt 272 fixing bolt 273 spacer 274 spring 30 therapy beam assembly 31 therapy beam 32 axis of therapy beam 33 accelerator therapy head 331 multi-leaf collimator 332 leaf 333 leaf moving frame 35 therapy beam imaging unit 361 rotor 362 stator 40 fan beam CT assembly 41 diagnostic beam 42 axis of diagnostic beam 43 fan beam CT tube 44 shielding body 45 diagnostic beam detecting unit 452 detector 50 pulse modulator 60 magnetron 72 water cooling device 722 water cooling pipe 724 expansion tank 74 water distributor 76 water inlet pipe 78 water return pipe 80 vibration sensor 82 counterweight device DETAILED DESCRIPTION

[0048] In order to make the objects, technical solutions and advantages of the present application clearer, the following will clearly and completely describe the technical solutions of the present application with specific embodiments of the present application and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0049] In the present document, "exemplary" means "serving as an example, instance, or illustration", and should not be construed as a more preferred or advantageous technical solution.

[0050] For the purpose of simplicity and brevity of the drawings, only the parts related to the present application are shown in the drawings, which do not represent the actual structure of the product. In addition, for the purpose of simplicity and brevity of the drawings, in some drawings, only one of the parts having the same structure or function is shown schematically, or only one of the parts is labeled.

[0051] The technical solutions provided by the embodiments of the present application are described in detail below with reference to the drawings.

[0052] Fig. 1 is a perspective view illustrating an exemplary embodiment of a radiotherapy device. As shown in Fig. 1, the radiotherapy device comprises a fixed base 10, a rotating gantry 20, a treatment beam assembly 30 and a fan-beam CT assembly 40.

[0053] The rotating gantry 20 is rotatably arranged on the fixed base 10, and the treatment beam assembly 30 and the fan-beam CT assembly 40 are arranged on the rotating gantry 20, so that the rotating gantry 20 can rotate the treatment beam assembly 30 and the fan-beam CT assembly 40 together.

[0054] Fig. 1 shows the treatment beam 31 of the treatment beam assembly 30 by a dashed line, and shows the diagnostic beam 41 of the fan-beam CT assembly 40 by a dashed line. After the rotating gantry 20 rotates, the axis 32 (see Fig. 2) of the treatment beam 31 rotates in a rotating plane. After the rotating gantry 20 rotates, the axis 42 (see Fig. 2) of the diagnostic beam 41 also rotates in a rotating plane.

[0055] In the present application, the rotating plane in which the axis 32 of the treatment beam 31 is located and the rotating plane in which the axis 42 of the diagnostic beam 41 is located are coincident with each other, i.e., are located in the same plane, and the axis 32 of the treatment beam 31 and the axis 42 of the diagnostic beam 41 intersect at the rotating shaft 22 of the rotating gantry 20, as shown in Fig. 2. In the present application, the axis is defined as an imaginary line formed along the central emission direction of the treatment beam or the diagnostic beam.

[0056] After the above design, the rotating frame 20 can drive the treatment beam assembly 30 and the fan-beam CT assembly 40 at the same time, so that the radiotherapy and CT imaging can be realized. Since the rotating plane of the axis of the treatment beam of the accelerator treatment head in the treatment beam assembly is coplanar with the rotating plane of the axis of the diagnostic beam of the fan-beam CT assembly, the axis 32 of the treatment beam 31 and the axis 42 of the diagnostic beam 41 intersect at the rotating shaft 22 of the rotating frame 20, so that the patient does not need to be displaced when switching between the CT imaging and the radiotherapy, so that the centers of the treatment and the imaging intersect at one point, the positioning is accurate, the treatment plan based on the CT imaging is more accurate, the traditional displacement compensation does not need to be considered during the treatment, the treatment can be directly implemented, the image error can be avoided, and the treatment is more accurate; when switching from the treatment working state to the diagnostic working state, the treatment beam assembly is controlled to return to the preset position, so that the components of the treatment beam assembly are protected from being damaged due to high-speed rotation, the high-speed rotation is in a dynamic balance state, the whole device is protected, and the device as a whole can reach a high rotating speed of 80 RPM to perform CT imaging.

[0057] In addition, since the radiotherapy device simultaneously integrates the treatment beam assembly and the fan-beam CT assembly, after the CT diagnosis of the patient is completed, the radiotherapy plan can be directly implemented without other preparation processes, so that the implementation steps are simplified, and the treatment process is improved and optimized.

[0058] In the embodiments shown in FIGS. 1 and 2, the treatment beam assembly 30 includes an accelerator treatment head 33, a pulse modulator 50, a magnetron 60, and a treatment beam imaging unit 35 opposite to the accelerator treatment head 33, and the treatment beam imaging unit 35 is, for example, a flat panel detector. The fan-beam CT assembly 40 includes a fan-beam CT tube 43 and a diagnostic beam detection unit 45 opposite to the fan-beam CT tube 43, and the diagnostic beam detection unit 45 is, for example, a plurality of arc-shaped detectors 452 as shown in the figure. The axis 32 of the treatment beam 31 and the axis 42 of the diagnostic beam 41 are perpendicular to each other. Preferably, the treatment beam imaging unit 35 includes an electronic portal imaging device (EPID, Electronic Portal Imaging Device), which is an important device in the accelerator quality control detection technology, and can further include a radiation detection device and a radiation signal processing device.

[0059] The above-mentioned arrangement that the axis 32 of the treatment beam 31 and the axis 42 of the diagnostic beam 41 are perpendicular to each other can make the layout of the overall structure more reasonable, mainly considering two reasons:

[0060] First, the therapy beam assembly 30 and the fan-beam CT assembly 40 are both heavy equipment, and during the rotation of the gantry 20, especially during the CT imaging process, high-speed continuous rotation is required. Therefore, the positional relationship among the accelerator therapy head 33, the therapy beam imaging unit 35, the fan-beam CT tube 43, and the diagnostic beam detection unit 45 needs to be reasonably distributed to ensure that the center of gravity is as close as possible to the rotation shaft 22 of the gantry 20.

[0061] Second, the accelerator therapy head 33 is usually at a mega-volt (MV) level, and the fan-beam CT tube 43 is usually at a kilo-volt (KV) level. When the accelerator therapy head 33 emits radiation or the fan-beam CT tube 43 emits radiation, damage to other components is possible. Therefore, the above arrangement can minimize the above damage.

[0062] In the embodiment shown in FIG. 2, the pulse modulator 50 is arranged between the accelerator therapy head 33 and the diagnostic beam detection unit 45, and the pulse unit of the pulse modulator 50 is arranged along the radial direction pointing to the rotation shaft 22. The magnetron 60 is arranged between the accelerator therapy head 33 and the fan-beam CT tube 43, and the magnetron 60 is arranged along the radial direction pointing to the rotation shaft 22.

[0063] The pulse modulator 50 is used to control the high-voltage pulse entering the accelerator therapy head 33, and it needs to be arranged with the accelerator therapy head 33 on the gantry 20. The pulse modulator 50 is arranged along the radial direction pointing to the rotation shaft 22, which is consistent with the main stress direction after rotation, thereby protecting the internal structure of the pulse modulator 50.

[0064] The magnetron 60 is an electric vacuum device used to generate microwave energy, and it is also an important device for radiotherapy, which needs to be arranged with the accelerator therapy head 33 on the gantry 20. The magnetron 60 is arranged along the radial direction pointing to the rotation shaft 22, which can reduce the deflection and movement of the filament in the magnetron during high-speed rotation, and keep the position of the cathode stable, thereby improving the stability under high-voltage operation.

[0065] In the embodiments shown in FIG. 1 and FIG. 8, the accelerator therapy head 33 includes an acceleration tube, and the gantry 20 is provided with a fixed plate 21 having a through hole for the acceleration tube to pass through. A fixed ring 23 protruding along the outer edge of the through hole and an adjusting ring 24 embedded in the inside of the fixed ring 23 and concentric with the fixed ring 23 are arranged on the fixed plate 21. The acceleration tube passes through the fixed ring 23 and the adjusting ring 24 and is connected with the adjusting ring 24 through a mounting arm 26. Two pairs of jackscrews 25 are arranged on the fixed ring 23, and the two pairs of jackscrews 25 respectively pass through the fixed ring 23 and adjustably abut against the outer sidewall of the adjusting ring 24 to realize the position adjustment of the acceleration tube in the horizontal direction (X, Y direction).

[0066] As shown in FIG. 8, the mounting arm 26 comprises at least three cantilever arms, one end of the three cantilever arms is collectively formed into a connecting loop which is arranged outside the acceleration tube, and the other end of the three cantilever arms is arranged on the adjusting ring 24; each cantilever arm is adjustably connected with the adjusting ring 24 through a bolt assembly 27, so as to realize the position adjustment of the acceleration tube in the vertical direction; the bolt assembly 27 comprises at least a vertical adjusting bolt 271 and a fixing bolt 272 which penetrates the inside of the vertical adjusting bolt 271 and is screwed with the adjusting ring 24; the two ends of the vertical adjusting bolt 271 are respectively provided with a gasket 273, and the outside of the vertical adjusting bolt 271 is sleeved with a spring 274.

[0067] It should be noted that in the present application, the direction parallel to the ground and perpendicular to the rotating shaft can be defined as the X direction, the extending direction of the rotating shaft can be defined as the Y direction, and the direction perpendicular to the ground (orthogonal to the X direction and the Y direction) can be defined as the Z direction; therefore, in the present embodiment, the fixing ring 23 is respectively provided with two pairs of top screws which are distributed in the X direction and the Y direction, and one of the top screw holes of each pair of top screws in the X direction and the Y direction is also provided with a spring (for example, the top screws on the left side and the front side in FIG. 8); the two pairs of top screws respectively pass through the fixing ring 23 and abut against the outer side wall of the adjusting ring 24, and the springs also abut against the outer side wall of the adjusting ring 24;

[0068] As shown in FIG. 8, during the adjustment, the position of the acceleration tube in the horizontal direction can be adjusted by adjusting the four top screws in the horizontal direction. Due to the interference of the rack, the horizontal adjusting bolt on the left side is not convenient to adjust, therefore, the right bolt can be directly adjusted, and the acceleration tube is adjusted back by the elastic force of the spring, so as to realize the position adjustment of the adjusting ring 24 and the acceleration tube connected therewith in the X and Y directions, the adjustment is more convenient, and the mechanical interference is overcome. At the same time, during the adjustment, the spring always keeps the horizontal adjusting bolt in the compressed state to press against the adjusting ring 24, so that the adjustment accuracy of the horizontal adjusting bolt is more accurate.

[0069] Continuing to refer to FIG. 8, each of the three bolt assemblies 27 includes a vertical adjusting bolt 271 and a fixing bolt 272 which is screwed through the interior of the vertical adjusting bolt 271 and is screwed with the adjusting ring 24, and when the vertical adjusting bolt 271 is adjusted in place, the fixing bolt 272 is tightened to press the vertical adjusting bolt 271, thereby fixing the bolt assembly 27. The upper end and the lower end of the vertical adjusting bolt 271 are provided with a pair of gaskets 273, i.e. the lower end of the vertical adjusting bolt 271 is abutted against the adjusting ring 24 through a pair of gaskets, and the fixing bolt 272 can also press the upper end of the vertical adjusting bolt 271 through a pair of gaskets; thus, the height of the three cantilevers in the Z direction can be adjusted by screwing in or out of the vertical adjusting bolt 271, so as to adjust the vertical height of the accelerating tube. Meanwhile, the fitting surfaces of the gaskets are provided as curved surfaces, i.e. the fitting surface of the upper end gasket of the vertical adjusting bolt is a curved surface, and the fitting surface of the lower end gasket of the vertical adjusting bolt and the adjusting ring 24 is also a curved surface, so that in the adjusting process, the curved surfaces between the two pairs of gaskets can slide relative to each other, thereby achieving fine adjustment; in addition, the spring 274 which is sleeved outside the vertical adjusting bolt 271 can press tightly, thereby improving the adjusting accuracy.

[0070] In addition, in the embodiment shown in FIG. 2, the radiotherapy device further includes a water cooling device 72, a water distributor 74, a water inlet pipe 76 and a water return pipe 78. The water cooling device 72 is arranged on the rotating frame 20 and is arranged outside the therapy beam imaging unit 35 along the radial direction of the rotating shaft 22. The water distributor 74 is arranged on the rotating frame 20 and is arranged between the accelerator therapy head 33 and the fan-beam CT tube 43 to provide cooling water for the accelerator heat generating components. The water inlet pipe 76 and the water return pipe 78 are connected between the water cooling device 72 and the water distributor 74, and the water inlet pipe 76 and the water return pipe 78 are arc-shaped pipes with the center of the circle located at the rotating shaft 22.

[0071] The water cooling device 72 can realize the cooling work of the accelerator therapy head 33, and arranging the water cooling device 72 on the rotating frame 22 is more conducive to the arrangement of the cooling pipeline. Of course, it should be understood that by adjusting the temperature of the water, the temperature can be raised in addition to being lowered, so that the components of the device are always close to the appropriate constant temperature.

[0072] Meanwhile, in the above scheme, the water distributor 74 and the magnetron 60 are arranged between the accelerator therapy head 33 and the fan-beam CT tube 43, the pulse modulator 50 is arranged between the accelerator therapy head 33 and the diagnostic beam detection unit 45, and the water cooling device 72 is arranged on the rotating frame 22 and is arranged outside the therapy beam imaging unit 35 along the radial direction of the rotating shaft 22, and the above layout can make the weight distribution more balanced, and can ensure the dynamic balance of the whole device after rotation, i.e. the arrangement of the water cooling device 72 itself can play a counterweight role.

[0073] It is also noted that the water inlet pipe 76 and the water return pipe 78 between the water cooling device 72 and the water distributor 74 are arranged as arc-shaped pipes, and the center of the arc-shaped pipes is located at the rotation shaft 22 of the rotating frame 20. With this design, the water hammer phenomenon can be avoided in the water inlet pipe 76 and the water return pipe 78 under high-speed rotation.

[0074] FIG. 3 is a schematic diagram illustrating a schematic embodiment of a water cooling system of the radiotherapy device. As shown in FIG. 3, the water cooling device 72 includes a water cooling pipe 722 arranged along the tangential direction of the rotating frame 20, and further includes an expansion tank 724 connected with the water cooling pipe 722 and arranged parallel to the rotating shaft 20. In the prior art, in order to reduce the volume, the water cooling pipe is arranged vertically and folded, and the expansion tank 724 is also arranged vertically. The arrangement of the present application is also considered in view of the stress direction of the water cooling device 72 under high-speed rotation, so as to ensure that the entire device is more stable.

[0075] In addition to the water cooling device for cooling the components of the device described above, the radiotherapy device is also provided with an air cooling device. The air cooling device includes an outdoor unit, an indoor unit and a pipeline of an air conditioning device. The outdoor unit is a variable frequency type. The air conditioning indoor unit sends cold air into the device housing through the air pipe to cool the entire device. The return air of the device housing is communicated with the air conditioning indoor unit and finally returns to the air conditioning indoor unit. The air conditioning indoor unit can be installed on the ceiling or in the pit of the device room. A plurality of temperature sensors are arranged in the device housing. When one of the temperature sensors detects that the temperature exceeds a certain threshold value, the control system controls the air cooling device to increase the air supply amount and reduce the air supply temperature for rapid cooling. In the normal working state, the air supply amount and the air supply temperature of the air cooling device are different in the treatment working state and the diagnosis working state. In the diagnosis working state, the temperature is lower, the air supply temperature is lower, and the air supply amount is larger. When the radiotherapy device switches from the treatment working state to the diagnosis working state, the control system controls the air cooling device to adjust the temperature.

[0076] In the embodiments shown in FIGS. 1 and 2, the radiotherapy device further includes a shielding body 44 movably arranged on the radially inner side of the diagnosis beam detection unit 45. The shielding body 44 has a shielding position capable of shielding the diagnosis beam detection unit 45 when the accelerator treatment head 33 is working, and an open position capable of exposing the diagnosis beam detection unit 44 when the fan-beam CT tube 43 is working. For example, in some embodiments, the shielding body 44 has a stepped structure, the thickness of the shielding body 44 near the treatment beam imaging unit 35 is relatively thick, and then the thickness gradually decreases in a stepped manner, and the shielding body 44 can be installed on a shielding body mounting seat. A driving motor is installed on the shell of the diagnosis beam detection unit 45. The shielding body mounting seat is driven by the driving motor, and can drive the shielding body 44 to reciprocate along the Z direction of the rotation shaft 22 of the rotating frame 20.

[0077] As described above, after the treatment beam assembly 30 and the fan-beam CT assembly 40 are arranged in the same rotating stand 20, the problem of radiation damaging other devices needs to be considered, especially the accelerator treatment head 33 of the treatment beam assembly 30 is usually Mega Volt (MV), and the rays are reflected to other positions when working. Although the above problem has been avoided as much as possible by arranging the axis of the treatment beam and the axis of the diagnostic beam perpendicular to each other, the protection of the diagnostic beam detection unit 45 can be further improved by arranging the shielding body 44, and the shielding body 44 is arranged in a stepped shape, so that the protection of the strong reflection area close to the treatment beam imaging unit 35 is stronger, and the reflection of the rays is smaller at the far position, and the thickness does not need to be too thick, which can reduce the weight of the shielding body, so that the treatment beam assembly 30, the fan-beam CT assembly 40 and other components can be reasonably arranged in the limited space, and the protection of the fan-beam CT assembly 40 when the treatment beam assembly 30 works can be improved. Of course, the thickness of the shielding body 44 can be designed according to "GBZ / T 201.2-2011 Radiation Shielding Specification for Radiotherapy Machine Room", and the present application does not limit this.

[0078] In the embodiment shown in the present embodiment, the radiotherapy device further comprises:

[0079] The first driving device is used for driving the rotating stand 20 to rotate;

[0080] The first driving device comprises a rotor 361 and a stator 362;

[0081] The rotor 361 is annular and is used for driving the rotating stand 20 to rotate; a plurality of magnets are arranged on the rotor 361; the plurality of magnets are uniformly arranged along the circumference of the rotor 361;

[0082] The stator 362 is annular, is sleeved outside the rotor 361 and is fixedly connected with the fixed base 10; a plurality of groups of coils are arranged on the stator 362; the plurality of groups of coils are uniformly arranged along the circumference of the stator 362.

[0083] In addition, in the technical solution of the present application, the first driving device in the radiotherapy device can generate corresponding magnetic fields on the plurality of magnets on the rotor 361 in the working state; when a certain current is passed through the coils of the stator 362, a changing magnetic field is generated, which interacts with the magnetic field generated by the rotor 361 to generate an electromagnetic thrust, which drives the rotor 361 and the stator 362 to rotate. Since the stator 362 is fixed on the base, the rotor 361 will rotate under the action of the electromagnetic thrust, so as to drive the rotating frame 20 fixed with the rotor 361 to rotate, and drive the treatment beam assembly 30 and the fan beam CT assembly 40 to rotate around the rotating center axis. Therefore, when the treatment beam assembly 30 or the fan beam CT assembly 40 needs to be used, the first driving device can be used to drive the treatment beam assembly 30 or the fan beam CT assembly 40 to rotate to the corresponding position.

[0084] Since the first driving device can directly drive the rotating frame 20 without the need to set gears, gearboxes and other structures, the treatment beam assembly 30 and the fan beam CT assembly 40 can be controlled to stably operate at variable speeds, high speeds and ultra-low speeds, and the highest rotating speed can reach 80 RPM.

[0085] The present application also provides a control method of a radiotherapy device, which at least comprises the fixed base 10, the rotating frame 20, the treatment beam assembly 30 and the fan beam CT assembly 40 shown in FIG. 1, the rotating frame 20 is rotatably arranged on the fixed base 10, the rotating frame 20 is provided with the treatment beam assembly 30 and the fan beam CT assembly 40, so that the rotating frame 20 can drive the treatment beam assembly 30 and the fan beam CT assembly 40 to rotate together. The rotating plane of the axis 32 of the treatment beam 31 of the treatment beam assembly 30 is coplanar with the rotating plane of the axis 42 of the diagnostic beam 41 of the fan beam CT assembly 40, and the axis 32 of the treatment beam 31 and the axis 42 of the diagnostic beam 41 intersect at the rotating shaft 22 of the rotating frame 20.

[0086] The treatment beam assembly 30 comprises an accelerator treatment head 33 and a treatment beam imaging unit 35 arranged opposite to the accelerator treatment head 33, and the treatment beam imaging unit 35 is for example a flat panel detector. The fan beam CT assembly 40 comprises a fan beam CT tube 43 and a diagnostic beam detection unit 45 arranged opposite to the fan beam CT tube 43, and the diagnostic beam detection unit 45 is for example a plurality of arc-shaped arranged detectors 452 as shown in the figure. The axis 32 of the treatment beam 31 and the axis 42 of the diagnostic beam 41 are arranged perpendicular to each other.

[0087] The radiotherapy device further comprises a pulse modulator 50 and a magnetron 60. The pulse modulator 50 is arranged on the gantry 20 and between the accelerator treatment head 33 and the diagnostic beam detection unit 45, and the pulse modulator 50 is arranged along a radial direction of the rotation axis 22. The magnetron 60 is arranged on the gantry 20 and between the accelerator treatment head 33 and the fan-beam CT tube 43, and the magnetron 60 is arranged along a radial direction of the rotation axis 22.

[0088] The control method can control the radiotherapy device to enter a treatment working state or a diagnostic working state. In the treatment working state, the gantry is controlled to drive the treatment beam assembly to move to a treatment position to implement radiotherapy. In the diagnostic working state, the gantry is controlled to drive the fan-beam CT assembly to continuously rotate to implement diagnostic imaging.

[0089] The control method further comprises, before switching from the treatment working state to the diagnostic working state, controlling the treatment beam assembly 30 to return to a preset position. After switching to the diagnostic working state, it is detected whether the treatment beam assembly 30 deviates from the preset position. If it is detected that the treatment beam assembly 30 deviates from the preset position, the gantry 20 is controlled to reduce the speed and enter a low-speed protection state.

[0090] As described above, in the CT imaging process, high-speed continuous rotation is required, and the treatment beam assembly 30 and the fan-beam CT assembly 40 are both heavy equipment. Therefore, after the treatment beam assembly 30 works, the influence of continuous high-speed rotation on the treatment beam assembly 30 needs to be considered, and the influence of the treatment beam assembly 30 on the dynamic balance after high-speed rotation also needs to be considered. The above control method takes the above influences into consideration, protects the components of the treatment beam assembly from being damaged due to high-speed rotation, and enables high-speed rotation to be in a dynamic balance state, thereby protecting the entire device.

[0091] In addition, during the high-speed rotation process, if the treatment beam assembly deviates from the preset position, the gantry 20 is controlled to reduce the speed, so that the entire device enters a low-speed protection state, thereby preventing the equipment from being damaged due to the broken dynamic balance.

[0092] Please refer to FIG. 4, which is used to illustrate the specific control steps before switching from the treatment working state to the diagnostic working state. FIG. 4 is only illustrative, and the steps are not in a specific order in the actual working condition. In addition, the treatment beam assembly 30 of the radiotherapy device can comprise a field diaphragm, the accelerator treatment head can comprise a multi-leaf collimator 331, and the radiotherapy device can comprise a water cooling device 72 and a fan arranged on the gantry 20.

[0093] As shown in FIG. 4, after it is found that the diagnostic working state is ready to be switched in step S10, it can enter steps S12, S14 and S16, wherein the steps are not in a specific order, and finally enter step S20 to switch to the diagnostic working state. In steps S12, S14 and S16,

[0094] Step S12, resetting the treatment beam assembly 30 to the preset position, further comprising steps S122 and S124:

[0095] Step S122, resetting the multi-leaf collimator 331, which is located on the underside of the fixed plate 21, so that the moving direction of the leaves 332 (indicated by the double-headed arrow in the figure) is parallel to the rotating shaft 22 (see FIG. 2) of the rotating frame 20. After resetting, the moving direction of the leaves 332 is always perpendicular to the tangential direction of rotation at high speed, not only protecting the leaves 322, but also avoiding displacement of the leaves 322. In addition, step S122 can further comprise resetting a pair of leaf moving frames 333 of the multi-leaf collimator 331, which are capable of relative movement and carry the leaves 332 when working. The resetting control causes the pair of leaf moving frames 333 to drive the leaves 322 to reset to a symmetric position, i.e., to reset to a symmetric position on both sides of the center line in the plane of the leaves 322 and the leaf moving frames 333, thereby reducing the impact on dynamic balance at high speed.

[0096] Step S124, resetting the field diaphragm of the treatment beam assembly 30. The field diaphragm (not shown in the figure) is usually arranged in pairs. The above-mentioned step control causes the paired field diaphragms to reset to a symmetric position, thereby reducing the impact on dynamic balance at high speed.

[0097] Step S14, reducing the water supply of the water cooling device 72 (see FIGS. 2 and 3) to a preset supply value, so as to reduce the water pressure and flow of the water cooling system. After switching to the diagnostic working state, the treatment beam assembly 30 is not working, and the heat dissipation demand is reduced. At this time, reducing the water supply of the water cooling device 72 can also ensure basic heat dissipation, and can reduce the impact of water flow on the treatment beam assembly 30 (mainly the accelerator treatment head) at high speed.

[0098] Step S16, reducing the rotating speed of the fan (not shown in the figure) of the radiotherapy device to a preset rotating speed value. The fan also plays a role in cooling the treatment beam assembly 30. After switching to the diagnostic working state, high-speed rotation will cause the fan to generate greater vibration and noise, which is easy to damage. At this time, reducing the rotating speed of the fan can reduce the above-mentioned vibration and noise, improve the service life of the fan, and improve the user experience.

[0099] After switching to the diagnostic working state, the control method of the present application further comprises a step of controlling the rotating frame 20 to reduce speed and enter a low-speed protection state. As shown in FIG. 6, this step further comprises the following steps:

[0100] Step S32, detecting the allowable force of each component provided on the rotating frame in the tangential direction of rotation;

[0101] Step S34, comparing the stress allowable values of each component, and obtaining the acceleration allowable value of the rotating frame according to the minimum stress allowable value;

[0102] Step S36, obtaining the maximum deceleration curve of the rotating frame according to the acceleration allowable value;

[0103] Step S38, controlling the rotating frame to reduce the rotating speed according to the maximum deceleration curve, and entering the low-speed protection state.

[0104] The above control method can avoid sudden deceleration during high-speed rotation, and the impact on the components on the rotating frame 20, and the deceleration process can also form a buffer for the subsequent emergency stop of the rotating action.

[0105] In addition to detecting that the treatment beam assembly is out of its preset position, the rotating frame can also be controlled to enter the low-speed protection state in other cases. For example, referring to FIG. 7, the radiotherapy device can also be provided with a plurality of vibration sensors 80, which can be uniformly arranged around the rotating shaft 22 of the rotating frame 20. Each vibration sensor 80 can sense the vibration data at the corresponding position, and once the vibration data of any vibration sensor 80 exceeds the first preset vibration threshold, the rotating frame 20 is controlled to enter the above-mentioned low-speed protection state to form protection for the radiotherapy device.

[0106] It can be understood that before entering the imaging state, the rotor in the radiotherapy device will enter a stationary state, and after the shielding body 44 and the leaf moving frame 333 return to the symmetric position so that the leaves 332 move to the direction parallel to the rotating shaft, it will slowly speed up and enter the high-speed state to reach the required position. Therefore, the radiotherapy device can achieve static balance through calibration operation in low-speed and stationary states, but in high-speed state, the accelerator treatment head 33, the treatment beam imaging unit 35, the fan-beam CT tube 43 and the diagnostic beam detection unit 45 and the like have a large weight, so the above-mentioned components will expand and deviate under the action of centrifugal force, and because the weight, structure and strength of each component are not the same, they will also deform differently, which will cause the machine to produce a large vibration in high-speed state. To solve the above problem, in some embodiments, a plurality of counterweight devices 82 corresponding to each vibration sensor 80 can also be provided to adjust the counterweight and achieve dynamic balance adjustment of the device.

[0107] Referring to FIG. 7, the control method further comprises, after entering the low-speed protection state due to the vibration data of the vibration sensor exceeding the above-mentioned first preset vibration threshold, adjusting the counterweight position of the counterweight structure in the counterweight device 82 at the corresponding position according to the vibration sensor that sends the vibration data, to dynamically adjust the overall counterweight on the rotating frame 20 to meet the requirements of high-speed rotation.

[0108] The control method further comprises: when the vibration data detected by the vibration sensor exceeds the second preset vibration threshold, controlling all power supplies of the radiotherapy device except the gantry to be disconnected, and the gantry gradually slows down to enter a low-speed protection state, and is powered off after a specific rotating speed, so that the gantry can slow down to a low-speed state and stop in an emergency, thereby protecting the radiotherapy device and improving the safety of use.

[0109] In some preferred embodiments, four sets of counterweight devices 82 are arranged on the gantry, each of the four sets of counterweight devices 82 comprising a second driving device and a counterweight structure movable by the second driving device, and each of the four sets of counterweight devices 82 being installed at a suitable position close to the accelerator treatment head 33, the treatment beam imaging unit 35, the fan-beam CT tube 43, and the diagnostic beam detection unit 45.

[0110] For example, the second driving device is provided with two parallel first worms arranged radially along the gantry 20, the first worms are provided with first sliding blocks, a second worm arranged perpendicular to the direction of the first worms is arranged between the two first sliding blocks, the second worm is provided with a second sliding block, the second sliding block is hollow and has a plurality of threaded holes (for example, four threaded holes) inside, each threaded hole is screwed with a third sliding block, and the third sliding block is a lifting block arranged uniformly along the axis of the gantry 20, and the third sliding block is driven to rotate by a rotary motor to realize self-rotation and self-lifting along the threaded hole. In addition, the rotary motor is provided with a brake to prevent movement at high speed.

[0111] The advantages of the counterweight device in the embodiments of the present application mainly include: on the one hand, by configuring different numbers and positions of lifting blocks in each second sliding block, the weight can be adjusted more flexibly, which is more conducive to the trimming of different weight treatment heads and other components, and thus the static balance adjustment of the device can be realized in the static state. On the other hand, before the state switching, the speed can be reduced, and the positions of the counterweight structures in the four counterweight devices are adjusted according to the real-time detection results of the vibration sensor, and finally the vibration is reduced to within the error allowable range. During the adjustment process, the rotary motor drives the worm to realize the position adjustment of the first sliding block and the second sliding block in the radial direction / vertical to the radial direction, and the rotary motor drives the third sliding block to rotate and lift to realize the position adjustment of the third sliding block in the axial direction, so as to accurately adjust the gravity center of the lifting block in the axial direction, and thus the dynamic balance adjustment of the device is more accurately realized.

[0112] The control method further comprises: before entering the treatment working state or the diagnosis working state, performing online monitoring to determine that the axis of the treatment beam and the axis of the diagnostic beam intersect at the rotating shaft of the gantry. Of course, in addition to the above-mentioned case, online monitoring can also be performed regularly, periodically or on demand, which is not limited here.

[0113] It can be understood that, since the radiotherapy device of the present application is calibrated before leaving the factory, the axis of the treatment beam, the axis of the diagnostic beam and the rotation axis intersect at the rotation center, that is, the isocenter of the treatment beam and the diagnostic beam are located at the mechanical center position, and the mechanical center position can be pre-marked after adjustment is completed, and each time the patient is treated and imaged, the target region position is moved to the pre-marked mechanical center position.

[0114] Therefore, the purpose of the online monitoring function provided by the present application is to determine whether the treatment beam and the diagnostic beam intersect at the rotation axis, that is, whether the treatment beam center and the imaging beam center are located at the mechanical center position, before treatment and imaging, and to calibrate the deviations of the components of the radiotherapy device by comprehensively analyzing the measurement indexes. For example, first, the in-place accuracy of the treatment bed is measured, and if there is no in-place error, the Winston-lutz test is performed to analyze the consistency of the treatment beam center and the mechanical center; then, the consistency of the imaging beam center and the mechanical center is analyzed through imaging. Through the pre-treatment and pre-imaging checks, it is ensured that the imaging beam center and the treatment beam center intersect at the isocenter, thereby ensuring the accuracy of treatment and imaging and ensuring the original design of the device.

[0115] The specific measurement process includes but is not limited to the following cases: measuring the numerical deviation of the physical distance (the distance between the imaging center and the mechanical center position) of the treatment beam imaging unit to determine whether there is an imaging error in the treatment beam imaging unit; measuring whether there is an in-place accuracy deviation; analyzing the consistency of the radiation center of the treatment beam and the mechanical center position (i.e., the isocenter of the treatment beam radiation) through treatment testing, and analyzing the consistency of the imaging center of the diagnostic beam and the mechanical center position through CT imaging testing.

[0116] After the above-mentioned measurements are completed, the numerical deviation of the physical distance, the in-place accuracy deviation, and the consistency results can be comprehensively analyzed to calibrate each component such as the treatment beam assembly and the fan beam CT assembly; for example, if the treatment beam center deviates from the rotation axis, the accelerating tube can be adjusted through the accelerating tube adjusting device (such as adjusting the position of the adjusting ring and the cantilever) to adjust the accelerating tube, thereby ensuring that the axis of the treatment beam intersects at the mechanical center position (isocenter) and ensuring that the overall device is in a static balance state.

[0117] In addition, the present application can also measure and adjust other components in the device, for example, the accuracy of the motion speed of the multi-leaf collimator, the in-place accuracy deviation of the leaf, and the like, and calibrate based on the deviation results, which will not be described here. Of course, the above content is only a demonstrative description and cannot be understood as a limitation of the present application.

[0118] In some embodiments, the online monitoring comprises: installing the phantom to be tested at a fixed position of the treatment bed, and moving the phantom center to a pre-calibrated mechanical center position; controlling the treatment beam assembly to image the phantom, and analyzing to obtain a numerical deviation of the physical distance between the imaging center of the treatment beam imaging unit and the pre-calibrated mechanical center position;

[0119] In some embodiments, the online monitoring further comprises: installing the phantom to be tested at a fixed position of the treatment bed, and moving the phantom center to a pre-calibrated mechanical center position; controlling the treatment bed to move multiple times in different directions respectively, and after each movement, performing imaging by the treatment beam assembly once;

[0120] In specific operations, the phantom center can be first moved to a laser virtual center (located outside the machine), and after other initial operations, the phantom center is moved from the laser virtual center to the mechanical center position by automatic walking of the treatment bed; then the treatment bed is controlled to move multiple times in different directions respectively, and after each movement, imaging is performed by the treatment beam assembly once;

[0121] By superimposing the current imaging and the previous imaging, the positioning accuracy deviation of the treatment bed in different directions is analyzed respectively; the position of the treatment bed is adjusted according to the numerical deviation and the positioning accuracy deviation, and the phantom center is moved to the pre-calibrated mechanical center position again; the treatment beam assembly is controlled to perform Winston-lutz test on the phantom, and the consistency result of the radiation center of the treatment beam and the mechanical center position is analyzed, and the treatment beam assembly is registered;

[0122] It can be understood that the multiple movements of the treatment bed need to be performed in opposite directions, and the movement distance of the treatment bed in opposite directions should be kept consistent, so that the multiple movement positions are symmetrical to each other. For example, in the embodiment, the step of determining the positioning accuracy deviation comprises:

[0123] The treatment bed is moved in the Y direction by a first distance (such as m distance), and the phantom is imaged by the treatment beam assembly for the first time. Through the first imaging, the positioning accuracy deviation of the treatment bed moving in the Y direction by the first distance is analyzed; the treatment bed is moved in the opposite direction of the Y direction by 2m distance (i.e. moving m distance to the initial position and then moving m distance in the opposite direction), and the phantom is imaged by the treatment beam assembly for the second time. The first imaging and the second imaging are superimposed, and the positioning accuracy deviation of the treatment bed moving in the opposite direction of the Y direction by 2m distance is analyzed;

[0124] moving the treatment couch a second distance (such as n distance) in the X direction, performing a third imaging of the phantom by the treatment beam assembly, and analyzing the deviation of the positioning accuracy of the movement of the treatment couch a second distance in the X direction by superimposing the third imaging and the second imaging;

[0125] moving the treatment couch a third distance (such as L distance) in the Z direction, performing a fifth imaging of the phantom by the treatment beam assembly, and analyzing the deviation of the positioning accuracy of the movement of the treatment couch a third distance in the Z direction by superimposing the fifth imaging and the fourth imaging; moving the treatment couch 2L distance in the reverse direction of the Z direction, performing a sixth imaging of the phantom by the treatment beam assembly, and analyzing the deviation of the positioning accuracy of the movement of the treatment couch 2L distance in the reverse direction of the Z direction by superimposing the sixth imaging and the fifth imaging;

[0126] Further, performing EPID image acquisition of the phantom by the treatment beam assembly, registering the center of the phantom to the image center position in the EPID image, and obtaining the registration result of the phantom; performing Winston-lutz test of the phantom by the treatment beam assembly, and analyzing the consistency of the radiation center and the mechanical center position of the treatment beam in combination with the registration result to adjust the treatment beam assembly.

[0127] When the radiation center of the treatment beam deviates from the mechanical center position, adjusting the accelerating tube by the accelerating tube adjustment device to make the treatment beam exit at the mechanical center, and when the center coordinate of the phantom after imaging (i.e. the projection coordinate value of the image center position of the phantom in the EPID coordinate system) and the projection coordinate value of the mechanical center in the EPID are consistent, it is considered that the phantom has been moved to the mechanical center.

[0128] Performing CT imaging of the phantom by the fan-beam CT assembly, and analyzing the consistency of the imaging center and the mechanical center position of the diagnostic beam. Further, moving the center of the phantom to the mechanical center position again, controlling the fan-beam CT assembly to emit a beam to guide the phantom, and analyzing the projection coordinate value of the image center position of the phantom in the EPID coordinate system by EPID image acquisition; and correcting the deviation between the projection coordinate value of the image center position and the mechanical center coordinate value (i.e. the projection coordinate value of the mechanical center in the EPID) by adjusting the CT assembly.

[0129] In a specific implementation, the mechanical center position is measured by a specific tooling and calibrated by a metal marker point, so the projection coordinates of the marker point of the mechanical center position in the EPID image can be obtained by the treatment beam. For example, the coordinates (a, b) of the metal marker point on the EPID image are obtained by using image analysis software, the phantom center is considered to be at the mechanical center position by moving the phantom position and collecting the EPID image so that the metal ball at the center of the phantom reaches the coordinates (a, b); then, the kilovoltage image is collected by the fan-beam CT assembly, under the guidance of the CT assembly graphics, the center of the phantom is registered to the image center in the EPID image, and the registration result, i.e., the deviation between the image center position and the mechanical center position, is observed in real time; if the deviation value is within the preset error range, no adjustment is needed, if the deviation value does not meet the preset error range, the CT ball tube needs to be adjusted, and the above steps are repeated until the deviation requirement is met.

[0130] Therefore, through online monitoring before diagnosis and treatment, it is ensured that the axes of the diagnosis beam and the treatment beam intersect at the mechanical center position, so as to ensure the accuracy of treatment and imaging, avoid image errors, and make the treatment more accurate.

[0131] It should be noted that each step of the control method of the radiotherapy device described above can be used to control the radiotherapy device provided in the foregoing embodiments, and the related explanations of the radiotherapy device are applicable to the control method of the radiotherapy device, which will not be repeated here.

[0132] The above is only a specific implementation of the present application, and those skilled in the art can make other improvements or modifications on the basis of the above embodiments under the above teaching of the present application. Those skilled in the art should understand that the above specific description is only for better explanation of the purpose of the present application, and the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. Radiotherapy device, characterized in that, It comprises: a fixed base; a rotating frame rotatably arranged on the fixed base; a therapeutic beam assembly arranged on the rotating frame, the therapeutic beam assembly comprising an accelerator treatment head, a pulse modulator, a magnetron and a therapeutic beam imaging unit arranged opposite to the accelerator treatment head; a fan-beam CT assembly arranged on the rotating frame, the fan-beam CT assembly comprising a fan-beam CT tube and a diagnostic beam detection unit arranged opposite to the fan-beam CT tube; an axis of a therapeutic beam of the accelerator treatment head and an axis of a diagnostic beam of the fan-beam CT assembly are coplanar and intersect at a rotation axis of the rotating frame, the axis of the therapeutic beam and the axis of the diagnostic beam are perpendicular to each other and coplanar; the pulse modulator is arranged between the accelerator treatment head and the diagnostic beam detection unit, a pulse unit of the pulse modulator is arranged along a radial direction pointing to the rotation axis; the magnetron is arranged between the accelerator treatment head and the fan-beam CT tube, the magnetron is arranged along a radial direction pointing to the rotation axis; an online monitoring module is configured to determine whether the axis of the therapeutic beam and the axis of the diagnostic beam intersect at the rotation axis of the rotating frame before entering a therapeutic working state or a diagnostic working state.

2. The radiotherapy device of claim 1, wherein, The radiotherapy device further comprises: a water cooling device arranged on the rotating frame and arranged outside the therapeutic beam imaging unit along a radial direction pointing to the rotation axis; a water distributor arranged on the rotating frame and arranged between the accelerator treatment head and the fan-beam CT tube to provide cooling water for accelerator heat generating components; and a water inlet pipe and a water return pipe connected between the water cooling device and the water distributor, the water inlet pipe and the water return pipe are arc-shaped pipes with a center at the rotation axis.

3. The radiotherapy device of claim 2, wherein, The water cooling device comprises: a water cooling pipe arranged along a tangential direction of rotation of the rotating frame, and an expansion tank arranged parallel to the rotation axis and connected with the water cooling pipe.

4. The radiotherapy device of claim 1, wherein, Further comprising a shielding body movably arranged radially inside the diagnostic beam detection unit, the shielding body has a shielding position capable of shielding the diagnostic beam detection unit when the accelerator treatment head is working, and an opening position capable of exposing the diagnostic beam detection unit when the fan-beam CT tube is working; a thickness of the shielding body is stepwise reduced from one end close to the therapeutic beam imaging unit.

5. The radiotherapy device of claim 1, wherein, The accelerator treatment head comprises an accelerating tube, a fixing plate is arranged on the rotating frame, the fixing plate is provided with a through hole for the accelerating tube to pass through; the fixing plate is provided with a fixing ring protruding along an outer edge of the through hole and an adjusting ring embedded in an inner part of the fixing ring and concentric with the fixing ring; the accelerating tube passes through the fixing ring and the adjusting ring and is connected with the adjusting ring through a mounting arm; the fixing ring is provided with two pairs of jacks, the two pairs of jacks respectively pass through the fixing ring and adjustably abut against an outer sidewall of the adjusting ring to realize position adjustment of the accelerating tube in a horizontal direction. The mounting arm comprises at least three cantilevers, one end of the three cantilevers is connected to the accelerator tube, and the other end of the three cantilevers is arranged on the adjusting ring; Each cantilever is adjustably connected to the adjusting ring by a bolt assembly, so as to adjust the position of the accelerator tube in the vertical direction; the bolt assembly comprises at least a vertical adjusting bolt and a fixing bolt penetrating the vertical adjusting bolt and being screwed with the adjusting ring; the vertical adjusting bolt is provided with a gasket at each end, and the vertical adjusting bolt is externally sleeved with a spring.

6. The radiotherapy device of claim 1, wherein, The radiotherapy device further comprises: A first driving device is configured to drive the rotating frame to rotate; The first driving device comprises a rotor and a stator; The rotor is annular and configured to drive the rotating frame to rotate; the rotor is provided with a plurality of magnets; the plurality of magnets are uniformly arranged along the circumference of the rotor; The stator is annular, is sleeved on the outside of the rotor, and is fixedly connected with the fixed seat; the stator is provided with a plurality of groups of coils, and the plurality of groups of coils are uniformly arranged along the circumference of the stator.

7. A control method of a radiation therapy apparatus, characterized by, The control method for the radiotherapy device of any one of claims 1 to 6 comprises: Controlling the radiotherapy device to enter a treatment working state, in which the rotating frame drives the treatment beam assembly to move to a treatment position to implement radiotherapy; Controlling the radiotherapy device to enter a diagnosis working state, in which the rotating frame drives the fan-beam CT assembly to continuously rotate to implement diagnostic imaging; The control method further comprises: Before switching from the treatment working state to the diagnosis working state, controlling the treatment beam assembly to return to a preset position, After switching to the diagnosis working state, detecting whether the treatment beam assembly deviates from the preset position, and if the deviation is detected, controlling the rotating frame to decelerate and enter a low-speed protection state; The control method further comprises: Before entering the treatment working state or the diagnosis working state, performing online monitoring to determine whether the axis of the treatment beam and the axis of the diagnostic beam intersect at the rotation axis of the rotating frame.

8. The control method according to claim 7, characterized by, The step of controlling the rotating frame to enter the low-speed protection state further comprises: detecting the allowable force of each component arranged on the rotating frame in the tangential direction of rotation, obtaining the acceleration allowable value of the rotating frame according to the minimum allowable force, obtaining the maximum deceleration curve of the rotating frame according to the acceleration allowable value, controlling the rotating frame to decelerate according to the maximum deceleration curve and enter the low-speed protection state.

9. The control method according to claim 7, characterized by, The online monitoring comprises: installing a phantom to be tested on a fixed position of a treatment bed and moving the center of the phantom to a mechanically calibrated center position; controlling the treatment bed to move in different directions for multiple times, and performing imaging by the treatment beam assembly after each movement; controlling the treatment beam assembly to perform EPID image acquisition on the phantom, registering the center of the phantom to the image center position in the EPID image, and obtaining a registration result of the phantom. controlling the therapy beam assembly to perform a Winston-lutz test on the phantom, and analyzing the consistency of the radiation center of the therapy beam with the mechanical center position based on the registration results to adjust the therapy beam assembly; controlling the fan-beam CT assembly to perform CT imaging on the phantom, and analyzing the consistency of the imaging center of the diagnostic beam with the mechanical center position to adjust the fan-beam CT assembly.

10. The control method according to claim 9, characterized by, The method of controlling the fan-beam CT assembly to perform CT imaging on the phantom, and analyzing the consistency of the imaging center of the diagnostic beam with the mechanical center position further comprises: moving the center of the phantom to the mechanical center position again; controlling the fan-beam CT assembly to emit a beam to perform graphic guidance on the phantom, and analyzing the projection coordinate value of the imaging center of the phantom in the EPID coordinate system based on the EPID image acquisition; adjusting the fan-beam CT assembly to correct the deviation between the projection coordinate value of the imaging center and the EPID mechanical center coordinate value.

11. The control method according to claim 7, characterized by, The radiotherapy device further comprises a plurality of vibration sensors, and the control method further comprises: when vibration data detected by one of the vibration sensors exceeds a first preset vibration threshold, controlling the rotating gantry to enter the low-speed protection state.

12. The control method according to claim 11, characterized by, The radiotherapy device further comprises at least four counterweight devices corresponding to the vibration sensors, each of the counterweight devices comprising a second driving device and a counterweight structure movable by the second driving device, The control method further comprises: After the rotating gantry enters the low-speed protection state due to the vibration data of the vibration sensor exceeding the first preset vibration threshold, adjusting the counterweight position of the counterweight structure in the counterweight device corresponding to the vibration sensor according to the vibration sensor that sends the vibration data.

13. The control method according to claim 11, wherein The control method further comprises: When the vibration data detected by the vibration sensor exceeds a second preset vibration threshold, controlling all power sources of the radiotherapy device except the rotating gantry to be disconnected, and gradually reducing the rotating speed of the rotating gantry to enter the low-speed protection state until the rotating gantry is powered off at a specific rotating speed.

14. The control method of claim 7, wherein the accelerator treatment head of the radiotherapy device comprises a multi-leaf collimator, and the step of controlling the therapy beam assembly to return to the preset position further comprises: returning the multi-leaf collimator, so that the moving direction of the leaves of the multi-leaf collimator is parallel to the rotating shaft of the rotating gantry.

15. The control method of claim 14, wherein the multi-leaf collimator comprises a pair of leaf moving frames capable of relative movement and carrying the leaves, and the step of controlling the therapy beam assembly to return to the preset position further comprises: returning the leaf moving frames of the multi-leaf collimator, so that the pair of leaf moving frames return to a symmetrical position with each other.

16. The control method of claim 7, wherein the therapy beam assembly of the radiotherapy device comprises a pair of field diaphragms, and the step of controlling the therapy beam assembly to return to the preset position further comprises: returning the field diaphragms, so that the field diaphragms return to a symmetrical position with each other. ​ ​ ​ 17. The control method according to claim 7, wherein the radiation therapy apparatus further comprises a water cooling device for maintaining a constant temperature of an accelerator heat generating device, and wherein Before switching from the treatment working state to the diagnosis working state, the method further comprises: reducing the water supply amount of the water cooling device to a preset supply value.

18. The control method of claim 7, wherein the radiation therapy device further comprises a fan disposed in the gantry. Before switching from the treatment working state to the diagnosis working state, the method further comprises: reducing the rotating speed of the fan to a preset rotating speed value.

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