Composite collimator and control method thereof, radiotherapy system and dose delivery method thereof

Abstract

The invention provides a composite collimator and a control method thereof, a radiotherapy system and a dose delivery method thereof, relates to the technical field of radiotherapy, is used for shaping a radiation beam emitted by a radiation source, and comprises a first blade group and a second blade group which are sequentially arranged along the direction of a beam center axis, the collimation body and the second blade group are arranged on the same layer and are orthogonally arranged; the first blade group and the second blade group respectively comprise a plurality of blades, and the plurality of blades move to form a grating channel through which a radiation beam can pass; the collimation body is provided with a collimation channel, and the collimation body can move relative to a beam center axis; when the collimation body moves to enable the collimation channel to be located at a beam current central axis, a radiation beam forms a focusing radiation field in a target area through a grating channel formed by the first blade group and the collimation channel; and when the collimation body moves to enable the collimation channel to deviate from the beam current central axis, the radiation beam forms a conformal radiation field in the target area through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group.

Description

Technical Field

[0001] The present application relates to the technical field of radiotherapy, and in particular to a composite collimator and a control method thereof, a radiotherapy system and a dose delivery method thereof. Background Art

[0002] Gamma Knife uses stereotactic and focused irradiation, which is suitable for the precise removal of small tumors. Using Gamma Knife to treat large lesions will produce "hot spots" or "cold spots" in the lesions, making it impossible to completely remove the lesions or causing excessive damage to surrounding organs. In addition, gamma rays have poor penetrating power. When treating body tumors, the tissue absorbs a large dose and has obvious side effects. Gamma Knife has a low dose rate, a long irradiation time, and a poor patient experience.

[0003] Based on this, medical linear accelerators are usually used for irradiation therapy through conformal intensity modulation. This method uses a multi-leaf grating to accurately adjust the irradiation field, making the irradiation field and the target area highly conformal, greatly protecting the surrounding organs and improving the treatment efficiency. However, due to process limitations and material problems, the thickness of the blades cannot be made relatively small, and the thickness of the blades determines the field accuracy. Therefore, the current linear accelerator is suitable for large-volume treatment, but not suitable for particularly small areas with many surrounding endangered organs, especially the treatment of head tumors. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a composite collimator and a control method thereof, a radiotherapy system and a dose delivery method thereof, which can realize switching between different radiation fields and improve field accuracy.

[0005] In one aspect of an embodiment of the present application, a composite collimator is provided for shaping a radiation beam emitted by a radiation source, comprising: a first blade group and a second blade group sequentially arranged along a central axis of the beam, and a collimator arranged in the same layer and orthogonally with the second blade group;

[0006] Wherein, the first blade group and the second blade group respectively include a plurality of blades, and the plurality of blades move to form a grating channel through which the radiation beam can pass;

[0007] A collimation channel is arranged on the collimator, and the collimator can move relative to the central axis of the beam; when the collimator moves so that the collimation channel is located at the central axis of the beam, the radiation beam forms a focused field in the target area through the grating channel and the collimation channel formed by the first blade group; when the collimator moves so that the collimation channel deviates from the central axis of the beam, the radiation beam forms a conformal field in the target area through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group.

[0008] The embodiment of the present application further provides a radiotherapy system, including a treatment bed, a frame and a treatment head, wherein the treatment head is arranged on the frame, and the treatment bed is used to carry the patient to move for treatment;

[0009] The treatment head includes a radiation source and the above-mentioned composite collimator which are arranged in sequence. The composite collimator constrains the radiation beam emitted by the radiation source into a preset radiation field in the target area.

[0010] The present application also provides a dose delivery method for a radiotherapy system, which is used to deliver a dose to the above-mentioned radiotherapy system. The method includes:

[0011] Obtain treatment plan information for the target subject;

[0012] The compound collimator of the treatment head is controlled according to the treatment plan information so that the radiation beam guided to the target area passes through the collimation channel of the collimator and the grating channel formed by the first blade group, or the radiation beam passes through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group.

[0013] The embodiment of the present application further provides a control method of a composite collimator, which is used to control the composite collimator. The method includes:

[0014] Acquiring irradiation information of a target object;

[0015] When it is determined according to the irradiation information that the target object is irradiated with a focused radiation field, the collimation channel of the collimator and the grating channel of the first blade group are controlled to be located at the central axis of the beam, so that the radiation beam emitted by the radiation source forms a focused radiation field in the target area after passing through the collimation channel and the grating channel;

[0016] When it is determined according to the irradiation information that the target object is irradiated with a conformal field, the collimation channel is controlled to deviate from the central axis of the beam so that the radiation beam emitted by the radiation source forms a conformal field through the grating channel formed by the first blade group and the grating channel formed by the second blade group.

[0017] The composite collimator and control method thereof, radiotherapy system and dose delivery method thereof provided in the embodiment of the present application, the composite collimator, the first blade group and the second blade group are sequentially arranged in the direction of the central axis of the beam, the first blade group and the second blade group respectively include a plurality of blades, and the movement of the plurality of blades forms a grating channel through which the radiation beam can pass; the second blade group is also provided with a collimator in the same layer and orthogonally, the collimator is provided with a collimator channel, and the collimator can move relative to the central axis of the beam. When the collimator moves to the point where the collimator channel is located at the central axis of the beam, the radiation beam passes through the grating channel and the collimator channel formed by the first blade group to form a focused radiation field in the target area; the second blade group moves closer to the central axis of the beam, and the blade ends of the second blade group fit with the two sides of the collimator to block the leakage of the surrounding radiation beams. When the collimator moves to make the collimation channel deviate from the central axis of the beam, the radiation beam forms a conformal radiation field in the target area through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group; at this time, when only one blade group is located at the central axis of the beam and the radiation beam passes through its grating channel, the other blade group that has not moved to the central axis of the beam can play a role in shielding the radiation leaking out of the field. The composite accurate device realizes the switching between different radiation fields. The clinician can choose the focused radiation field or the conformal radiation field according to the needs, improve the adaptability, greatly improve the treatment efficiency, and provide a guarantee for improving the cure rate.

[0018] The radiotherapy system uses relative swing between the treatment bed and the gantry to make the angle between the treatment bed and the gantry different, so that the radiation beam is emitted from different angles.

[0019] Through their respective control methods, the system control can be realized simply and efficiently. Based on the combined irradiation of the two field modes, their respective advantages can be brought into play. Through flexible irradiation plans, the overall therapeutic effect of the radiotherapy system can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 is a simplified schematic diagram of the radiotherapy system provided in this embodiment;

[0022] Figure 2 is a simplified schematic diagram of the radiotherapy system provided in this embodiment;

[0023] Figure 3 is a simplified schematic diagram of the radiotherapy system provided in this embodiment;

[0024] Figure 4ais a side schematic diagram of the composite collimator provided in this embodiment;

[0025] Figure 4b is a schematic diagram of the structure of the composite collimator provided in this embodiment;

[0026] Figure 5 is another schematic diagram of the structure of the composite collimator provided in this embodiment;

[0027] Figure 6 is another schematic diagram of the structure of the composite collimator provided in this embodiment;

[0028] Figure 7 is another schematic diagram of the structure of the composite collimator provided in this embodiment;

[0029] Figure 8 is a schematic diagram of the swing of the treatment bed of the radiotherapy system provided in this embodiment;

[0030] Fig. 9 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0031] Fig.10 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0032] Fig.11 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0033] Fig.12 is a schematic diagram of the structure of the radiotherapy system provided in this embodiment;

[0034] Fig.13 is a schematic diagram of the swing of the radiotherapy system frame provided in this embodiment;

[0035] Fig.14 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0036] Fig.15 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0037] Fig.16 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0038] Fig.17 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0039] Fig.18 It is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment.

[0040] Icons: 10-radiation source; 10a-radiation beam; 121-first blade group; 122-second blade group; 12.1-blade; 13-collimator; 13a-collimator channel; 131-collimator sub-body; 131a-concave side wall; 132-guide rail; 14-rotating disk; 100A-radiation delivery device; 100-gantry; 100a-treatment space; 100b-gantry rotation axis; 101-outer cover; 102-tray; 102a-rectangular hole; 110a-base; 111a-first arc guide rail; 110b- Base; 111b-arc guide rail; 111b1-first arc guide rail; 111b2-second arc guide rail; 112b-gear ring; 113b-gear; 113b1-motor; 120-second rack drive device; 200-treatment bed; 201-second circular arc guide rail; 202-first slider; 203-second slider; 300a-tube; 300b-detector; 400-slave control system; 500-master control system; 600-treatment planning system; 700-memory; O-isocenter; S-lowest point of rack. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0042] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0043] It should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] Radiotherapy refers to local treatment with radiation to eliminate and cure the primary or metastatic lesions of local tumors.

[0045] Based on this, the present application embodiment provides a radiotherapy system (referred to as radiotherapy system), such as Figure 1-Figure 3As shown, it includes a gantry 100, a treatment head, and a treatment bed 200; wherein the treatment bed 200 is used to support and move the patient; the treatment head includes a radiation source 10 and a collimator, the radiation source 10 emits a radiation beam 10a to the target area, and the collimator guides the radiation beam 10a to the target area into a preset radiation field of a specific shape, so that the radiation irradiated on the patient's part is adapted to the tumor; the gantry 100 is installed with various radiotherapy components, and drives the treatment head to rotate around the gantry rotation axis 100b to emit radiation beams 10a from different angles.

[0046] For example, Figure 1 As shown, the gantry 100, the treatment head and the treatment bed 200 constitute an integrated radiation delivery device 100A; the radiotherapy system also includes a main control system 500, a slave control system 400, a treatment planning system 600, and a memory 700; in some embodiments, the radiation delivery device 100A, the main control system 500, the slave control system 400, the treatment planning system 600, and the memory 700 can be connected and / or communicate with each other via a wireless connection (e.g., a network connection), a wired connection, or a combination thereof.

[0047] In some embodiments, the master control system 500 may be used to generate control instructions for one or more components of the radiation therapy system (eg, the slave control system 400 , the treatment planning system 600 , the memory 700 ).

[0048] In some embodiments, the slave control system 400 may be used to control the radiation delivery device 100A to perform corresponding actions in response to control instructions generated by the master control system 500 .

[0049] In some embodiments, the treatment planning system 600 is configured to determine a treatment plan based on a planning image of the patient (a planning image is an image of the patient acquired using an imaging device before treatment) and / or at least a portion of an object (e.g., a tumor) represented in an image acquired based on an imaging system.

[0050] The memory 700 may store data, instructions, and / or any other information. In some embodiments, the memory 700 may store data obtained from the treatment planning system 600. In some embodiments, the memory 700 may store data and / or instructions used by the master control system 500 to perform the exemplary methods described in this application.

[0051] The radiation source 10 can generate or emit a radiation beam 10a, and the number of radiation sources 10 can be one or more. The radiation source can be an X-ray radiation source, a gamma-ray radiation source, or other electrons, protons, or heavy ions, etc. The present application does not limit the type of radiation source, and an X-ray radiation source is used as an example for illustration. The position of the radiation source 10 relative to the patient and the orientation of the radiation beam 10a relative to the patient can be achieved by controlling the movement of the gantry 100 and / or the treatment bed 200.

[0052] The treatment couch 200 is used to carry the patient P. The treatment couch 200 can be moved in three orthogonal directions (in Figure 1 In some embodiments, the treatment couch 200 may also be rotatable about any one or more of the three axes, X, Y, and Z.

[0053] The gantry 100 is used to support the treatment head and can drive the treatment head to rotate around the gantry rotation axis 100b. The gantry rotation axis 100b and the central axis of the radiation beam 10a intersect at the isocenter O.

[0054] The rack 100 includes a C-shaped rack, a roller rack, etc., and the present application takes the roller rack 100 as an example. Figure 2-Figure 3 As shown, a treatment space 100 a is formed on the gantry 100 , and the treatment couch 200 enters the treatment space 100 a , and treats the patient on the treatment couch 200 through various radiotherapy components on the gantry 100 .

[0055] For example, in an embodiment provided by the present application, the treatment bed 200 and the gantry 100 can be relatively deflected so that the angle between the treatment bed 200 and the gantry 100 is different, and the radiation beam 10a can be emitted from different angles to carry out coplanar and non-coplanar irradiation, providing a flexible field irradiation scheme, so that the patient can obtain a better treatment effect. In addition, during the treatment process, the gantry 100 can also rotate along the gantry rotation axis 100b so that the preset radiation field is emitted to the target area from different directions.

[0056] In some embodiments, the rack 100 is also provided with an imaging system, which is used to achieve precise radiotherapy; the imaging system includes a tube 300a and a detector 300b, and the tube 300a emits an imaging beam, which passes through the patient and is received by the detector 300b. By collecting patient images, it can provide information on the shape, volume and position of tumors and critical organs, and align with the images of the treatment plan to verify whether the patient is moving or accurately positioned. It can also adjust the patient, stop treatment or adjust the treatment plan based on the image alignment verification results; the images of some image guidance systems can also be used to formulate treatment plans; continuous dynamic images are used to observe and evaluate changes in the morphology and position of tumors and organs caused by physiological movements. In some embodiments, the imaging system can be, for example, a CT device, a cone beam CT device, a PET device, a volume CT device, an MRI device, or a combination thereof.

[0057] The imaging system may include one tube 300a and one detector 300b, or may include two tubes 300a and two detectors 300b, that is, include a first imaging system and a second imaging system, and the rays of the first imaging system and the second imaging system intersect.

[0058] When the system has a first imaging system and a second imaging system, the dual imaging system can be set up to perform three-dimensional imaging of the target area through a gantry 100 phase, thereby achieving real-time monitoring of the lesion position. The image data can be collected at the same time, which takes less time and improves the efficiency of image guidance.

[0059] In the embodiment provided by the present application, the collimator is used to make the radiation beam 10a directed to the target area into a preset field of a specific shape. After the electrons generate radiation during target shooting, they pass through the primary collimator to preliminarily conform the radiation beam 10a emitted by the radiation source 10, generally into a cone or square cone; the composite collimator provided by the present application constrains the preliminarily conformed radiation beam 10a into a preset field in the target area.

[0060] For example, when performing field irradiation, generally, conformal fields are selected for large body tumors, but focused fields are more accurate for small tumors. In order to provide a more flexible irradiation scheme for clinical applications, the composite collimator provided in the embodiment of the present application can achieve seamless switching between different fields. In addition, the focused field can also be used for local dose enhancement of tumors.

[0061] For examples, please refer to Figure 4a and 4b As shown, the present application provides a composite collimator for shaping a radiation beam 10a emitted by a radiation source, comprising:

[0062] A first blade group 121 and a second blade group 122 are sequentially arranged along the central axis of the beam, and a collimator 13 is arranged in the same layer and orthogonally to the second blade group 122;

[0063] The first blade group 121 and the second blade group 122 respectively include a plurality of blades 12.1, and the plurality of blades 12.1 move to form a grating channel through which the radiation beam can pass;

[0064] A collimating channel 13a is provided on the collimating body 13, and the collimating body 13 can move relative to the central axis of the beam; when the collimating body 13 moves so that the collimating channel 13a is located at the central axis of the beam, the radiation beam 10a forms a focused field in the target area through the grating channel formed by the first blade group 121 and the collimating channel 13a; when the collimating body 13 moves so that the collimating channel 13a deviates from the central axis of the beam, the radiation beam 10a forms a conformal field in the target area through the grating channel formed by the first blade group 121 and / or the grating channel formed by the second blade group 122.

[0065] The first blade group 121 and the second blade group 122 are arranged in two layers along the central axis of the beam, and the first blade group 121 and the second blade group 122 respectively include a plurality of blades 12.1. The plurality of blades of the first blade group 121 or the second blade group 122 can be adapted to form grating channels of different shapes through which the radiation beam can pass. For example, the blades 12.1 of the first blade group 121 and the blades 12.1 of the second blade group 122 are arranged in an overlapping manner, and the blades 12.1 of the second blade group 122 cover the gaps between the blades 12.1 of the first blade group 121.

[0066] For example, Figure 4a As shown, the first blade group 121 and the second blade group 122 can be respectively arranged in two boxes, and the two boxes are respectively located in the upper and lower layers. For example, the two boxes can be fixed separately or connected and fixed. Alternatively, the first blade group 121 and the second blade group 122 are arranged in the same box, and the first blade group 121 and the second blade group 122 are located in the upper and lower layers in the same box.

[0067] The blades 12.1 move to form a grating channel, that is, the first blade group 121 forms a grating channel, and the second blade group 122 also forms a grating channel. The grating channel can be used to allow the radiation beam 10a to pass through.

[0068] In one embodiment, the first blade group 121 is arranged close to the radiation source 10, and the second blade group 122 is arranged away from the side of the radiation source 10, that is, the radiation beam 10a emitted from the radiation source 10 first passes through the grating channel formed by the first blade group 121, and then passes through the grating channel formed by the second blade group 122. This application takes the case where the first blade group 121 is arranged close to the radiation source 10 and the second blade group 122 is arranged away from the side of the radiation source 10 as an example.

[0069] Of course, the second blade group 122 can also be arranged close to the radiation source 10, and the first blade group 121 can be arranged on the side away from the radiation source 10. In this case, the radiation beam 10a emitted from the radiation source 10 first passes through the grating channel formed by the second blade group 122, and then passes through the grating channel formed by the first blade group 121.

[0070] The composite collimator provided in the present application also includes a collimator 13, which is located at the same layer as the second blade group 122 and is arranged orthogonally to the second blade group 122; the collimator 13 can move relative to the central axis of the beam, and a collimator channel 13a is arranged on the collimator 13, and the collimator channel 13a is parallel to the central axis of the beam so that the central axis of the beam passes through.

[0071] When the collimator 13 moves, the collimator channel 13a can be located at the central axis of the beam. At this time, the second blade group 122 retreats away from the central axis of the beam and avoids the movement path of the collimator 13. After the radiation beam 10a passes through the grating channel of the first blade group 121 and the collimator channel 13a, a focused radiation field is formed in the target area; and after the second blade group 122 retreats from the central axis of the beam, it can move closer to the central axis of the beam, and the ends of the blades 12.1 of the second blade group 122 fit with the two sides of the collimator 13 to block the leakage of the surrounding radiation beam 10a; the formed focused radiation field is suitable for particularly small lesion areas with many surrounding endangered organs.

[0072] When the collimator 13 moves to the point where the collimation channel 13a deviates from the central axis of the beam, in one embodiment, both the first blade group 121 and the second blade group 122 can move to the central axis of the beam, and the radiation beam 10a passes through the grating channel formed by the first blade group 121 and the grating channel formed by the second blade group 122 to form a conformal field in the target area with higher conformal accuracy.

[0073] In one embodiment, any one of the first blade group 121 and the second blade group 122 can move to the central axis of the beam. At this time, the radiation beam 10a passes through the grating channel formed by the blade group moving to the central axis of the beam, that is, the radiation beam 10a passes through the grating channel formed by the first blade group 121 or the grating channel formed by the second blade group 122, and forms a conformal radiation field in the target area. The conformal radiation field is suitable for complex large radiation field lesions; the other blade group that has not moved to the central axis of the beam can approach the central axis of the beam to follow the edge of the complex large radiation field to block the radiation leakage outside the radiation field. Or, for example, a conformal radiation field is formed by one blade group, and intensity modulation is achieved by the movement of the blade 12.1 of another blade group.

[0074] Therefore, the composite collimator provided in the embodiment of the present application has a first blade group 121 and a second blade group 122 sequentially arranged in the direction of the central axis of the beam, and the first blade group 121 and the second blade group 122 respectively include a plurality of blades 12.1, and the plurality of blades 12.1 move to form a grating channel through which the radiation beam 10a can pass; the second blade group 122 also has a collimator 13 arranged in the same layer and orthogonally, and a collimator channel 13a is arranged on the collimator 13, and the collimator 13 can move relative to the central axis of the beam. When the collimator 13 moves to the point where the collimator channel 13a is located at the central axis of the beam, the radiation beam 10a passes through the grating channel and the collimator channel 13a formed by the first blade group 121 to form a focused radiation field in the target area, which can be used for the treatment of lesions that are particularly small and have many peripheral organs at risk; the second blade group 122 moves closer to the central axis of the beam, and the ends of the blades 12.1 of the second blade group 122 fit with the two sides of the collimator 13 to block the leakage of the surrounding radiation beam 10a. When the collimator 13 moves to make the collimation channel 13a deviate from the central axis of the beam, the radiation beam 10a forms a conformal field in the target area through the grating channel formed by the first blade group 121 and / or the grating channel formed by the second blade group 122, which can be used for the treatment of complex large field lesions; at this time, when only one blade group is located on the central axis of the beam and the radiation beam 10a passes through its grating channel, the other blade group that has not moved to the central axis of the beam can play a role in shielding radiation leaking out of the field.

[0075] For example, Figure 5 As shown, in the embodiment provided by the present application, a plurality of collimating channels 13a are provided on the collimating body 13, and the aperture sizes of the plurality of collimating channels 13a are different. When the collimating channels 13a of different sizes move to the central axis of the beam, focusing fields of different sizes can be formed. For example, the aperture size of the collimating channel 13a is generally less than 30cm; for example, the aperture size of the collimating channel 13a can be various, and the example sizes are 1cm, 3cm, 5cm, 7cm, 10cm, 12cm, 16cm, 18cm, 20cm, 25cm, etc., and those skilled in the art can set it according to actual needs.

[0076] The collimator 13 includes two collimator sub-bodies 131 arranged opposite to each other, wherein at least one of the two collimator sub-bodies 131 is provided with a collimator channel 13a, or the two collimator sub-bodies 131 are respectively provided with a collimator channel 13a. Figure 5 As shown, the embodiment of the present application and the accompanying drawings are described by taking the example that the two collimating bodies 13 are respectively provided with collimating channels 13a.

[0077] For example, Figure 5 A plurality of collimation channels 13a are respectively arranged on two opposite collimation sub-bodies 131, wherein the collimation channel 13a of one collimation sub-body 131 is larger than the collimation channel 13a of the other collimation sub-body 131, that is, the minimum collimation channel 13a of one collimation sub-body 131 is larger than the maximum collimation channel 13a of the other collimation sub-body 131, so that a plurality of collimation channels 13a of different sizes are distributed on the two collimation sub-bodies 131 for selection, thereby realizing rapid switching between approximate collimation channels 13a.

[0078] For example, Figure 5 As shown, two opposite collimating sub-bodies 131 may be mounted on a pair of guide rails 132 and may move forward and backward under the drive of a driving device, and their movement directions are perpendicular to the movement directions of the blades 12.1 of the second blade assembly 122 of the same layer.

[0079] For example, the collimating channel 13a includes a cylindrical channel or a conical channel. The embodiment of the present application takes the collimating channel 13a as a conical channel as an example for illustration. The cross-sectional size of the conical channel at one end close to the radiation source 10 is smaller than the cross-sectional size of the conical channel at one end away from the radiation source 10.

[0080] In the embodiment provided in the present application, the composite collimator is composed of a collimator 13 of a double-layer blade group and a conical collimation channel 13a. The collimator 13 and a blade group of the double-layer blade group near the patient are located in the same plane, and the movement directions of the two are orthogonal. When it is necessary to form a focused radiation field, the blades 12.1 of the second blade group 122 retreat to avoid the movement path of the collimator 13. After the selected collimation channel 13a on the collimator 13 moves to the central axis of the beam, the blades 12.1 of the second blade group 122 move closer to the central axis of the beam, and the ends of the blades 12.1 of the second blade group 122 fit with both sides of the collimator 13 to block the leakage of the surrounding radiation beam 10a. The blade group on the side near the target moves closer to the central axis of the beam to form a circular grating channel, and the actions of the above two layers of blade groups can be performed synchronously.

[0081] When it is necessary to use a blade group to form a conformal field, the collimator 13 moves away from the central axis of the beam to both sides to avoid the movement path of the blade group, and the blade group forms the required conformal field in a conventional manner. That is, the radiation beam 10a forms a conformal field in the target area through the grating channel formed by the first blade group 121 and / or the grating channel formed by the second blade group 122. For example, the radiation beam 10a may be formed in the target area through the grating channel formed by the first blade group 121 or the grating channel formed by the second blade group 122. The radiation beam 10a may also be formed in the target area through the grating channel formed by the first blade group 121 and the grating channel formed by the second blade group 122, that is, the first blade group 121 and the second blade group 122 jointly form a conformal field.

[0082] In order to reduce the size of the collimator 13 and reduce the leakage radiation outside the collimator channel 13a, for example, the side wall of the collimator 13 used to fit the end of the blade 12.1 in the present application is a concave side wall 131a ( Figure 5 as shown), to adapt to the shape of the end of the blade 12.1.

[0083] For example, the two sides of the collimator 13 are concave side walls 131a, which conform to the ends of the blades 12.1 of the second blade group 122, and the blades 12.1 of the second blade group 122 can fit tightly with the collimator 13. For example, when the collimator 13 moves so that the collimation channel 13a is located at the central axis of the beam, the radiation beam 10a passes through the grating channel of the first blade group 121 and the collimation channel 13a, and forms a focused radiation field in the target area; the second blade group 122 moves closer to the central axis of the beam, and the ends of the blades 12.1 of the second blade group 122 fit with the two sides of the collimator 13. The concave side walls 131a of the collimator 13 strengthen the tightness of the fit between the two, and better block the leakage of the surrounding radiation beam 10a. Figure 4b The diagram shows the close conformal fit between the leaf group and the collimator 13 on the patient side.

[0084] The above-mentioned composite collimator can realize the switching between different radiation fields; when the above-mentioned composite collimator is applied to the radiotherapy system of the present application, stereotactic and conformal intensity modulation integrated radiotherapy can be applied, and a single accelerator X-ray source is used as the radiation source 10 to carry out stereotactic and conformal intensity modulation therapy under a single-head system. The patient is positioned once, the lesion is accurately divided, and the lesion is treated in a targeted manner using stereotactic and conformal intensity modulation, which improves adaptability, greatly improves treatment efficiency, and provides a guarantee for improving the cure rate.

[0085] Through the coordinated movement of the frame and the treatment bed, a variety of incident angles are provided, which can achieve stereotactic orientation of the focusing hole and stereotactic orientation of the complex radiation field of the blade 12.1.

[0086] An embodiment of the present application also provides a radiotherapy system, including a treatment bed, a frame and a treatment head, wherein the treatment head is arranged on the frame, and the treatment bed is used to carry the patient to move for treatment; wherein the treatment head includes a radiation source and any composite collimator provided in the embodiment of the present application arranged in sequence, and the composite collimator constrains the radiation beam emitted by the radiation source to a preset radiation field in the target area.

[0087] In the embodiment provided in the present application, the radiotherapy system further includes a rotating disk 14, such as Figure 5 , Figure 7 As shown, the compound collimator is arranged on a rotating disk 14, and the compound collimator is driven to rotate by the rotating disk 14, so that the angles of the two sets of blades and the collimator 13 relative to the radiation source 10 are different, and the edge positions of the formed radiation fields are different.

[0088] When the compound collimator rotates to different angles, the position of the radiation field formed in the target area after the radiation beam 10a passes through remains substantially unchanged, but the edge of the formed radiation field will be located at different positions as the compound collimator rotates to adapt to different lesion shape requirements.

[0089] Through the above settings, the same radiation source 10 generates a point light source. Through the composite collimator, the switching of focused irradiation or conformal intensity modulated irradiation of the radiation field is realized. Stereotactic and rotational intensity modulated treatment can be carried out on the same device, which expands the treatment range and improves the degree of refinement of the treatment. The movement coordination of the frame and the treatment bed provides a rich incident angle, which can realize the stereotactic orientation of the focusing hole and the stereotactic orientation of the grating complex radiation field. Compared with the stereotactic device of gamma rays, the dose rate is high, the penumbra is small, the treatment time is shortened, and the treatment accuracy is improved.

[0090] In an embodiment provided by the present application, different angles are formed between the treatment couch and the gantry through relative deflection and swing between the treatment couch and the gantry, so that the radiation beam is irradiated from different angles.

[0091] In one embodiment of the present application, the gantry 100 and the treatment bed 200 are formed at different angles by the deflection and swing of the treatment bed 200 in the horizontal plane. For example, the gantry 100 rotates around the gantry rotation axis 100b, and the treatment bed 200 is swung in the horizontal plane, so that the angles between the treatment bed 200 and the gantry 100 are different.

[0092] In another embodiment of the present application, the rack 100 and the treatment bed 200 form different angles by swinging and deflecting the rack 100. After the patient is positioned, non-coplanar irradiation and focused irradiation can be achieved by swinging the rack 100. The patient does not need to move, the positioning accuracy is high, and the patient has a good treatment experience. There are no protrusions in the rack 100, and the patient has no risk of being squeezed, which improves the efficiency of non-coplanar irradiation. For example, the rack is set to swing in a horizontal plane so that the angle between the treatment bed and the rack is different.

[0093] As mentioned above, the movement of the collimator 13 makes the collimator channel 13 a located on or away from the central axis of the beam. The radiotherapy system further includes a guide rail 132 , on which the collimator 13 is disposed for movement of the collimator 13 .

[0094] In an embodiment provided by the present application, different angles are formed between the treatment couch and the gantry through relative deflection between the treatment couch and the gantry, so that the radiation beam is irradiated from different angles, that is, non-coplanar irradiation is achieved.

[0095] In one embodiment of the present application, Figure 8 As shown, different angles are formed between the gantry 100 and the treatment bed 200 by the deflection of the treatment bed 200. For example, the gantry 100 rotates around the gantry rotation axis 100b, and the treatment bed 200 is swung in a horizontal plane, so that the angles between the treatment bed 200 and the gantry 100 are different.

[0096] For details, please refer to Figure 9-10 As shown, in the radiotherapy system provided by the embodiment of the present application, the bottom of the treatment bed 200 is configured to be connected to the first arc guide rail 111a; the treatment bed 200 includes a first treatment bed driving device and a second treatment bed driving device, the first treatment bed driving device is used to drive the treatment bed 200 to move to enter the treatment space 100a, and the second treatment bed driving device is used to drive the treatment bed 200 to move along the first arc guide rail 111a, so that the treatment bed 200 rotates and swings in a horizontal plane.

[0097] By driving the first treatment bed driving device, the treatment bed 200 can enter the treatment space 100a along the gantry rotation axis 100b of the gantry 100; by driving the second treatment bed driving device, the treatment bed 200 can rotate and swing along the first arc guide rail 111a in the horizontal plane to form different angles with the gantry 100, so that the radiation beam 10a is emitted from different angles to achieve non-coplanar irradiation. For example, when the angle formed by the treatment bed 200 and the gantry 100 is 0°, it means that the axis of the treatment bed 200 is parallel to the gantry rotation axis 100b.

[0098] For example, the center of the first arc guide rail 111 a is coaxial with the isocenter O of the radiotherapy system.

[0099] Another embodiment provided by the present application is as follows: Fig.11 As shown, in order to ensure the stability of the support of the treatment bed 200, a second arc guide rail 201 is also provided at the bottom of the treatment bed 200. The two sets of arc guide rails are concentric and have different radii. For example, the first arc guide rail 111a is installed on the base 110a, and the frame 100 is set on the base 110a to make the structure more compact and the accuracy is easy to ensure.

[0100] When the treatment bed 200 is connected to the two sets of arc guide rails, the connection with the arc guide rails is achieved through sliders. For example, the slider can be connected to the treatment bed 200, or the guide rail can be connected to the treatment bed 200, and this application does not limit this. In the following embodiments, for example, a first slider 202 is set at the bottom of the treatment bed 200, and the treatment bed 200 is connected to the first arc guide rail 111a through the first slider 202. A second slider 203 is fixed on the ground, and the treatment bed 200 is connected to the second arc guide rail 201 and the second slider 203. A gap is formed between the bottom of the treatment bed 200 and the ground, and the treatment bed 200 is supported on the ground by the second slider 203 and the second arc guide rail 201.

[0101] Thus, the treatment bed 200 is supported by the circular arc guide rail and rotates around the isocenter axis to form non-coplanar irradiation. The guide rail of the first circular arc guide rail 111a is installed on the base 110a, and the first slider 202 moves with the treatment bed 200. For example, in order to enhance the support stability of the treatment bed 200, a second circular arc guide rail 201 is provided at the bottom of the treatment bed 200, and the guide rail of the second circular arc guide rail 201 is installed at the bottom of the treatment bed 200, and the second slider 203 is connected to the ground through a support frame. When the installation and positioning part of the circular arc guide rail is processed on the base 110a, the isocenter O point is used as a reference to ensure the reliability of accuracy.

[0102] like Fig.12 As shown, the frame 100 and the base 110a are integrally provided with an outer cover 101, the base 110a and the frame 100 are both located in the outer cover 101, the outer cover 101 is formed with a central opening matching the treatment space 100a, and the first arc guide rail 111a is located outside the outer cover 101. In this way, the frame 100 can operate at high speed in a closed shape, reduce the risk of patient collision, enhance the treatment experience, and improve the efficiency and safety of non-coplanar irradiation.

[0103] The shape adopts a closed shape, and the moving parts are wrapped inside the shape. The target area can be monitored in real time during the treatment. After adjusting the non-coplanar angle, during the irradiation process, the patient remains still relative to the shape, without the risk of scratches or collisions, thereby improving the accuracy and safety of the treatment.

[0104] The present application provides a radiotherapy system that achieves non-coplanar irradiation by swinging the treatment bed, providing a more flexible field irradiation plan for clinical treatment. The treating physician can adopt a more flexible irradiation method according to the patient's lesions to obtain a better dose distribution. In addition, during non-coplanar irradiation, there is no risk of collision, and the frame can rotate at high speed, which improves the efficiency and safety of treatment. In addition, as mentioned above, during the irradiation process, images can be collected through the image guidance system for patient positioning or real-time monitoring to ensure the treatment effect.

[0105] The above-mentioned method of swinging the treatment bed to form different angles relative to the frame realizes that the treatment bed forms different angles. In this case, the treatment bed needs to be moved after the patient is positioned on the treatment bed, which poses a risk of target area changes. In addition, the treatment bed is frequently moved during treatment to change non-coplanar angles, resulting in a poor treatment experience for the patient.

[0106] Therefore, in another embodiment of the present application, reference Figure 12-16 As shown, the rack 100 and the treatment bed 200 form different angles by swinging and deflecting the rack 100. After the patient is positioned, non-coplanar irradiation and focused irradiation can be achieved by swinging the rack 100. The patient does not need to move, the positioning accuracy is high, and the patient has a good treatment experience. There are no protrusions in the rack 100, and the patient has no risk of being squeezed, which improves the efficiency of non-coplanar irradiation.

[0107] During the treatment process, the non-coplanar movement of the gantry 100 can be automatically adjusted, and can be continuously and dynamically adjusted during the treatment process. According to the distribution of tissues around the target area, the non-coplanar path is adjusted to obtain a better target area dose distribution.

[0108] For examples, please refer to Fig.14 As shown, in the radiotherapy system provided by the embodiment of the present application, the treatment bed 200 is used to carry the patient and move to a preset position; and further includes a first frame driving device and a second frame driving device 120, the first frame driving device is used to drive the frame 100 to rotate along the frame rotation axis 100b, and the second frame driving device 120 is used to drive the frame 100 to rotate around the axis of the frame 100 isocenter O in the horizontal plane, so that the angle between the treatment bed 200 and the frame 100 is different, and the second frame driving device 120 is higher than the lowest point S of the frame (the lowest point of rotation of the frame 100), as shown in FIG. Fig.18 As shown. For example, the second rack drive device 120 includes multiple different drive components, and the second rack drive device 120 is higher than the lowest point S of the rack. Any one drive component or any multiple drive components in the second rack drive device 120 may be higher than the lowest point S of the rack. For example, the second rack drive device 120 includes a guide rail, a slider, and a motor. The guide rail may be higher than the lowest point S of the rack, and the motor may be set at any position. Alternatively, the guide rail, the slider, and the motor may all be higher than the lowest point S of the rack.

[0109] For example, Fig.14 As shown, in the embodiment of the present application, the radiotherapy system further includes a base 110b, which is fixed to the ground or floor, and the frame 100 is disposed on the base 110b and is rotationally connected to the base 110b via a second frame driving device 120, so that the frame 100 rotates and swings relative to the treatment bed 200 in a horizontal plane.

[0110] Among them, Figure 15-17As shown, similar to the swing structure of the treatment bed 200, the rack 100 swings through the guide rail and the slider. For example, the second rack drive device 120 includes an arc guide rail 111b, a slider and a driver; the arc guide rail 111b is set on the base 110b, the slider is set on the rack 100, and the driver is used to drive the slider to move along the arc guide rail 111b, so that the rack 100 rotates and swings relative to the treatment bed 200 in the horizontal plane; the center of the arc guide rail 111b is coaxial with the isocenter O of the radiotherapy system. For example, the arc guide rail 111b can also be set on the rack 100, and the slider can be set on the ground. This application does not limit this, and only uses the figure as an example for explanation.

[0111] For example, the arc guide rail 111b includes a first arc guide rail 111b1 and a second arc guide rail 111b2 which are arranged opposite to each other, and the first arc guide rail 111b1 and the second arc guide rail 111b2 are coaxial. For example, the first arc guide rail 111b1 and the second arc guide rail 111b2 are respectively located on both sides of the frame 100. For example, the first arc guide rail 111b1 and the second arc guide rail 111b2 are respectively located on both sides of the axis of the frame 100 to support the frame 100 to rotate from both sides. Correspondingly, the slide includes a first guide rail slider and a second guide rail slider, and the first guide rail slider and the second guide rail slider are respectively connected to the frame 100; or, the first guide rail slider and the second guide rail slider are connected by a connecting member, and the connecting member is connected to the frame 100.

[0112] For example, Fig.16 As shown, the connecting member may be a tray 102, the rack 100 is fixed on the tray 102, and the rack 100 is connected to the base 110b through the tray 102. The bottom of the rack 100 extends downward through the rectangular hole 102a on the tray 102, so that the arc guide rail 111b or the slider is higher than the lowest point S of the rack. In other words, the second rack driving device 120 is higher than the lowest point S of the rack, as shown in FIG. Fig.17 shown.

[0113] For example, the first curved guide rail 111b1 and the first guide rail slider (located on the first curved guide rail 111b1 and connected to the tray 102) are driven by the driver to drive the second guide rail slider (located on the second curved guide rail 111b2 and connected to the tray 102) to move along the second curved guide rail 111b2. In this way, when the rack 100 swings, it is guided by the first curved guide rail 111b1 and the second curved guide rail 111b2, which can increase the stability of the swing of the rack 100.

[0114] The drive provides power for the swinging of the frame 100. In one embodiment of the present application, the drive is a gear drive, including a motor 113b1, a gear 113b and a ring gear 112b, wherein the ring gear 112b is coaxial with the first arc-shaped guide rail 111b1, and the motor 113b1 drives the gear 113b to move along the ring gear 112b through a steering gear.

[0115] Thus, the arc guide rail 111b is installed on the base 110b, and its rotation axis is the swing rotation axis of the frame 100. The frame 100 is connected to the arc guide rail 111b through a slider. A gear ring 112b is installed on the base 110b, and the rotation center of the gear ring 112b is coaxial with the arc guide rail 111b. A driver is installed on the frame 100, and the gear 113b at the output end of the driver is meshed with the above-mentioned gear ring 112b. The driver drives the frame 100 to rotate and swing around the isocenter O through the meshing movement of the driving gear 113b and the gear ring 112b, so that the treatment bed 200 and the frame 100 form different angles, so that the radiation beam 10a is emitted from different angles.

[0116] For example, a positioning pin is provided at the bottom of the rack 100, and the base 110b is connected to the bottom of the rack 100 through the positioning pin. The distribution geometric center of the positioning pin is located on the rotation axis of the base 110b, so that the beam axis of the rack 100 and the rotation axis of the base 110b coincide with each other. The rack 100 swings around the beam center axis to achieve non-coplanar irradiation. Of course, when the rack 100 swings in the horizontal plane to an angle of 90° with the treatment bed 200, coplanar irradiation can be achieved.

[0117] In addition, an anti-collision strip is provided at the edge of the frame 100 near the treatment bed 200 to prevent the frame 100 from touching the treatment bed 200 when swinging, thereby affecting the treatment of the patient.

[0118] Through the above method, the patient can obtain a treatment space that is fixed relative to the ground. The patient cannot feel the high-speed rotation of the rack, and the patient experience is good. Non-coplanar irradiation is achieved by the swing of the rack. During the patient treatment, the rack swings to adjust the non-coplanar incident angle. After the patient is positioned, the patient's target area positioning accuracy is high, and the patient treatment experience is good. The rack can also swing while irradiating, with more incident paths, and the diseased core area can receive a higher dose of irradiation, the focal-skin ratio is further improved, and the dose outside the target area drops quickly, which can better carry out SBRT irradiation treatment.

[0119] On the other hand, the embodiment of the present application further provides a control method of a composite collimator, which is used to control the composite collimator. The method includes S10-S12:

[0120] S10: Obtaining irradiation information of the target object.

[0121] For example, the irradiation information may be treatment plan information received by the host computer or the slave computer. Acquiring the irradiation information of the target object includes using focused irradiation and using conformal irradiation, so as to determine different irradiation forms according to different treatment plans.

[0122] S11: When the target object is determined to be irradiated with a focused field according to the irradiation information, the collimation channel of the collimator and the grating channel of the first blade group are controlled to be located at the central axis of the beam, so that the radiation beam emitted by the radiation source forms a focused field in the target area after passing through the collimation channel and the grating channel. For example, when focused irradiation is used, it can be further determined which size of field to use.

[0123] For example, when using focused irradiation, the movement of the blades of the first blade group is controlled so that the grating channel of the first blade group is located at the central axis of the beam; the movement of the collimator is controlled so that the collimator channel is located at the central axis of the beam. At this time, the second blade group retreats away from the central axis of the beam and avoids the movement path of the collimator. After the radiation beam passes through the grating channel of the first blade group and the collimator channel, a focused radiation field is formed in the target area; and after the second blade group retreats from the central axis of the beam, it can move closer to the central axis of the beam, and the blade ends of the second blade group fit with both sides of the collimator to block the leakage of the surrounding radiation beams; the formed focused radiation field is suitable for particularly small lesion areas with many surrounding endangered organs. By controlling the composite collimator so that the radiation beam guided to the target area passes through the collimator channel and the grating channel, a focused radiation field can be formed in the target area.

[0124] S12: When it is determined according to the irradiation information that the target object is irradiated with a conformal field, the collimation channel is controlled to deviate from the central axis of the beam so that the radiation beam emitted by the radiation source forms a conformal field through the grating channel formed by the first blade group and the grating channel formed by the second blade group.

[0125] For example, the radiation beam may be formed by only the grating channel formed by the first blade group or the grating channel formed by the second blade group to form a conformal radiation field in the target area. The radiation beam may also be formed by the grating channel formed by the first blade group and the grating channel formed by the second blade group to form a conformal radiation field in the target area, that is, the first blade group and the second blade group jointly form a conformal radiation field.

[0126] For example, when a conformal field is used, the movement of the collimator is controlled so that the collimation channel of the collimator deviates from the central axis of the beam; the movement of the blades is controlled so that the grating channel of the first blade group and / or the second blade group is located on the central axis of the beam; the radiation beam passes through the grating channel to form a conformal field in the target area.

[0127] Through the control method, the collimator and the first blade group and the second blade group are controlled according to different irradiation information to generate the required focused radiation field or conformal radiation field. The whole process is simple and efficient.

[0128] The composite collimator is applied to a radiotherapy system. The embodiment of the present application provides a dose delivery method for the radiotherapy system, which is used to deliver a dose to the radiotherapy system. The method includes S20-S21:

[0129] S20: Obtain treatment plan information of the target object.

[0130] For example, the treatment plan information may be generated by the treatment plan system and sent to a host computer, which then sends it to each slave computer to control each component to execute the treatment plan information.

[0131] For example, the treatment plan information of the target object may include using coplanar irradiation or non-coplanar irradiation, and also includes using focused irradiation or conformal irradiation, so as to determine the field formation mode of the compound collimator and the swing mode of the gantry 100 and the treatment bed 200 according to different treatment plan information.

[0132] S21: Control the compound collimator of the treatment head according to the treatment plan information, so that the radiation beam guided to the target area passes through the collimation channel of the collimator and the grating channel formed by the first blade group, or the radiation beam passes through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group.

[0133] When the radiation beam passes through the collimation channel and the grating channel of the first blade group, a precise focused radiation field can be formed; when the radiation beam passes through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group, a conformal radiation field can be formed. That is, the field formation method is selected according to the above treatment plan information.

[0134] For example, in an optional embodiment of the present application, the dose delivery method of the radiotherapy system further includes:

[0135] The relative swing between the treatment bed and the gantry is controlled so that the radiation beam emitted by the treatment head is focused on the target area from different incident angles. Through the relative swing between the treatment bed and the gantry, coplanar irradiation or non-coplanar irradiation can be achieved to meet different treatment needs.

[0136] For example, the relative swing between the treatment bed 200 and the gantry 100 can be controlled by swinging the treatment bed 200 in a horizontal plane so that the radiation beam 10a emitted by the treatment head is focused on the target area from different incident angles. In this mode, by swinging the treatment bed 200, different angles are formed between the treatment bed 200 and the gantry 100, and the radiation beam 10a is emitted from different angles to achieve non-coplanar irradiation.

[0137] For example, in an optional embodiment of the present application, the dose delivery method of the radiotherapy system further includes: controlling the gantry 100 to swing in a horizontal plane so that the radiation beam 10a emitted by the treatment head is focused on the target area from different incident angles. At this time, by swinging the gantry 100, different angles are formed between the treatment bed 200 and the gantry 100, and the radiation beam 10a is emitted from different angles to achieve non-coplanar irradiation.

[0138] For the relative swinging manner between the treatment bed 200 and the frame 100, please refer to the above description for details.

[0139] The embodiment provided in the present application obtains more incident angles through the coordinated movement of the aforementioned gantry 100 and the treatment bed 200, and realizes stereotactic irradiation and rotational intensity modulation therapy. The incident angle is adjusted according to the location, shape and distribution of the lesion, maximizing the protection of the surrounding normal organs and delivering the dose to the target area. Based on the combined irradiation of the two field modes, the respective advantages are brought into play, the degree of refinement of the treatment is improved, and the overall treatment effect of the radiotherapy system is improved.

[0140] Different radiation fields (conformal radiation fields or focused radiation fields) can be selected according to the patient's lesions. The two radiation field methods can be quickly switched. The patient can be positioned once and two radiation methods can be used for combined irradiation, providing a more flexible approach for clinical applications. When making a treatment plan, it can be a single radiation field or a combination of two radiation fields.

[0141] When the two types of radiation fields are used in combination, the first blade group and / or the second blade group can be used to form a conformal radiation field for basic dose irradiation, which has a large coverage area; for the core area of ​​the lesion, a focused radiation field combined with non-coplanar radiation is used for focused irradiation to increase the dose in the target area and improve the cure rate of the tumor. For patients suitable for SBRT, a precise focused radiation field combined with non-coplanar radiation can be used for focused irradiation. Of course, a composite collimator can also be used for conventional conformal radiation intensity modulated irradiation.

[0142] The present application embodiment provides a dose delivery method for a radiotherapy system, including S100-S110:

[0143] S100: driving the treatment couch 200 so that the patient is located in the treatment space 100a of the gantry 100.

[0144] The treatment couch 200 can be driven by the first treatment couch driving device to enter the treatment space 100a for treatment.

[0145] S110: driving the treatment couch 200 to deflect along the first arc guide rail 111a, so that the treatment couch 200 and the gantry 100 form different angles, so that the radiation beam 10a is emitted from different angles.

[0146] The second treatment bed driving device drives the treatment bed 200 to move along the first arc guide rail 111 a, so that the treatment bed 200 rotates in a horizontal plane, so that the treatment bed 200 forms different angles with respect to the frame 100 .

[0147] Furthermore, the swing stability of the treatment bed 200 can be enhanced through the auxiliary effect of the second arc guide rail 201 .

[0148] For example, an embodiment of the present application provides a dose delivery method for a radiotherapy system, further comprising S120: a radiation beam 10a that is guided to a target area via a compound collimator forms a focused field or a conformal field along a radiation source beam. For example, the compound collimator can be any compound collimator provided in the present application. The specific method of driving the compound collimator can refer to the above-mentioned embodiment of the present application, which will not be described in detail here.

[0149] For example, the embodiment of the present application provides a dose delivery method for a radiotherapy system, further comprising S130: driving the gantry 100 to rotate along the gantry rotation axis 100b so that the focused field Ff or the conformal field Fc is directed to the target area from different orientations.

[0150] In actual applications, through the cooperation between the gantry 100 and the treatment bed 200, while the treatment bed 200 is used to move the patient, the gantry 100 can also be rotated to achieve better irradiation.

[0151] For example, the present application also provides a dose delivery method of a radiotherapy system, including S200-S210:

[0152] S200: driving the treatment couch 200 so that the patient is located in the treatment space 100a of the gantry 100.

[0153] S210: driving the gantry 100 to rotate in a horizontal plane so that the treatment bed 200 and the gantry 100 form different angles, so that the radiation beam 10a is emitted from different angles.

[0154] For example, the second gantry driving device 120 drives the gantry 100 to rotate in a horizontal plane, so that the gantry 100 forms different angles relative to the treatment bed 200 to achieve non-coplanar irradiation.

[0155] By way of example, the present application also provides a dose delivery method for a radiotherapy system, further comprising S220: directing a radiation beam 10a of radiation to a target area via a compound collimator to form a focused field or a conformal field along a radiation source beam.

[0156] For example, a composite collimator is provided with a first blade group and a second blade group in sequence in the direction of the central axis of the beam, and the first blade group and the second blade group respectively include a plurality of blades, and the movement of the plurality of blades forms a grating channel through which the radiation beam can pass; the second blade group is also provided with a collimator in the same layer and orthogonally, and a collimator channel is provided on the collimator, and the collimator can move relative to the central axis of the beam. When the collimator moves to the point where the collimator channel is located at the central axis of the beam, the radiation beam passes through the grating channel and the collimator channel formed by the first blade group to form a focused radiation field in the target area, which is used for the treatment of lesions that are particularly small and have many surrounding organs at risk; the second blade group moves closer to the central axis of the beam, and the blade ends of the second blade group fit with the two sides of the collimator to block the leakage of the surrounding radiation beams. When the collimator moves to make the collimation channel deviate from the central axis of the beam, the radiation beam forms a conformal radiation field in the target area through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group, which can be used to treat complex large radiation field lesions; at this time, when only one blade group is located at the central axis of the beam and the radiation beam passes through its grating channel, the other blade group that has not moved to the central axis of the beam can play a role in shielding the radiation leakage outside the field. The composite accurate device realizes the switching between different radiation fields, improves adaptability, greatly improves treatment efficiency, and provides a guarantee for improving the cure rate.

[0157] For example, the present application also provides a dose delivery method for a radiotherapy system, the method further comprising S230: driving the gantry 100 to rotate along the gantry rotation axis 100b so that the focused field Ff or the conformal field Fc is directed to the target area from different directions. The steps related to the control method are similar to those described above and can be referred to for execution.

[0158] For example, in addition to the above-mentioned swinging of the treatment bed 200 or the swinging of the rack 100, the treatment bed 200 and the rack 100 can also be swung simultaneously to achieve different angles between the two. Specific reference is made to the above-mentioned swinging of the treatment bed 200 and the swinging of the rack 100, which will not be repeated here.

[0159] For example, different irradiation modes can be used during irradiation: the gantry 100 and the treatment bed 200 move relative to each other to form an angle, and the gantry 100 continuously rotates along the gantry rotation axis 100b for non-coplanar irradiation. Dynamic stereotactic irradiation is supported, and the relative angle position of the gantry 100 and the treatment bed 200 is adjusted in real time during the irradiation process to obtain more incident angles, improve the focal-skin ratio, and improve the dose gradient around the target area.

[0160] For example, in the embodiments provided by the present application, the two field modes can be flexibly switched. A conformal field can be selected to efficiently perform basic dose irradiation, and then a precise focused field can be used to irradiate the core area inside the target area, which is more in line with the dose distribution requirements of SBRT.

[0161] For example, in the embodiments provided by the present application, conventional fixed field irradiation can only perform conformal irradiation and cannot adjust the intensity. The composite collimator of the present application adjusts the intensity within the fixed field range and can obtain accurate shape and dose distribution.

[0162] For example, in the embodiment provided by the present application, after the relative positions of the gantry 100 and the treatment bed 200 are adjusted, an arc irradiation can be completed. The irradiation process can select a single field mode or a combination of two field modes according to the planned dose distribution requirements.

[0163] The embodiment provided in the present application obtains more incident angles and realizes stereotactic irradiation through the coordinated movement of the aforementioned gantry 100 and the treatment bed 200. The incident angle is adjusted according to the location, shape and distribution of surrounding organs of the lesion, maximizing the protection of surrounding normal organs and delivering the dose to the target area. Based on the combined irradiation of the two field modes, the respective advantages are brought into play, the treatment accuracy is improved, and then the overall treatment effect of the radiotherapy system is improved.

[0164] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, 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 composite collimator, characterized in that: Used to shape the radiation beam emitted by the radiation source, comprising: a first blade group and a second blade group arranged in sequence along the central axis direction of the beam, and a collimator arranged in the same layer and orthogonally to the second blade group; Wherein, the first blade group and the second blade group respectively include a plurality of blades, and the plurality of blades move to form a grating channel through which the radiation beam can pass; A collimation channel is provided on the collimator, and the collimator can move relative to the central axis of the beam; when the collimator moves so that the collimation channel is located at the central axis of the beam, the radiation beam forms a focused field in the target area through the grating channel formed by the first blade group and the collimation channel; when the collimator moves so that the collimation channel deviates from the central axis of the beam, the radiation beam forms a conformal field in the target area through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group.

2. The composite collimator according to claim 1, characterized in that: The first blade group is arranged close to the radiation source, and the second blade group is arranged at a side away from the radiation source.

3. The composite collimator according to claim 2, characterized in that: When the collimator moves so that the collimator channel is located at the central axis of the beam, the ends of the blades of the second blade group fit with the two sides of the collimator to block the leakage radiation beam.

4. The composite collimator according to claim 3, characterized in that: The side wall of the collimator used to fit with the end of the blade is a concave side wall to adapt to the shape of the end of the blade.

5. The composite collimator according to claim 2, characterized in that: The blades of the first blade group and the blades of the second blade group are arranged in an overlapping manner, and the blades of the second blade group cover the gaps between the blades of the first blade group.

6. The composite collimator according to claim 1, characterized in that: The first blade group and the second blade group are respectively arranged in two boxes, or the first blade group and the second blade group are arranged in the same box.

7. The composite collimator according to claim 1, characterized in that: The collimating channel at least comprises a cylindrical channel or a conical channel, and the cross-sectional dimension of one end of the conical channel close to the radiation source is smaller than the cross-sectional dimension of one end of the conical channel far from the radiation source.

8. The composite collimator according to any one of claims 1 to 7, characterized in that: The collimating body is provided with a plurality of collimating channels, and the aperture sizes of the plurality of collimating channels are different.

9. The composite collimator according to claim 8, characterized in that: The collimator comprises two collimator sub-bodies arranged opposite to each other, wherein at least one of the two collimator sub-bodies is provided with the collimator channel, or the two collimator sub-bodies are respectively provided with the collimator channels.

10. The composite collimator according to claim 9, characterized in that: When the collimation channels are respectively arranged on the two collimation sub-bodies, the collimation channel of one of the collimation sub-bodies is larger than the collimation channel of the other collimation sub-bodies.

11. A radiotherapy system, characterized in that: It includes a treatment bed, a frame and a treatment head, wherein the treatment head is arranged on the frame, and the treatment bed is used to carry the patient to move for treatment; The treatment head comprises a radiation source and a compound collimator as claimed in any one of claims 1 to 10 which are arranged in sequence, and the compound collimator constrains the radiation beam emitted by the radiation source into a preset field in a target area.

12. The radiotherapy system according to claim 11, characterized in that: It also includes a guide rail, on which the collimator is arranged for movement of the collimator.

13. The radiotherapy system according to claim 11, characterized in that: It also includes a rotating disk, on which the compound collimator is arranged, and the compound collimator is driven to rotate by the rotating disk.

14. The radiotherapy system according to claim 11, characterized in that: The treatment couch and the gantry of the radiotherapy system swing relative to each other so that the angles between the treatment couch and the gantry are different.

15. The radiotherapy system according to claim 14, characterized in that: The treatment bed is swingably arranged in a horizontal plane; Alternatively, the frame is swung in a horizontal plane so that the angles between the treatment bed and the frame are different.

16. The radiotherapy system according to any one of claims 11 to 15, characterized in that: The radiotherapy system further comprises an image guidance system, and the image guidance system is arranged on the frame.

17. A dose delivery method of a radiotherapy system, characterized in that: For delivering a dose to a radiotherapy system according to any one of claims 11 to 16, the method comprising: Obtain treatment plan information for the target subject; The compound collimator of the treatment head is controlled according to the treatment plan information so that the radiation beam guided to the target area passes through the collimation channel of the collimator and the grating channel formed by the first blade group, or the radiation beam passes through the grating channel formed by the first blade group and / or the grating channel formed by the second blade group.

18. The dose delivery method of the radiotherapy system according to claim 17, characterized in that: The method further comprises: The relative swing between the treatment bed and the gantry is controlled so that the radiation beam emitted by the treatment head is focused on the target area from different incident angles.

19. The dose delivery method of the radiotherapy system according to claim 18, characterized in that: The method of controlling the relative swing between the treatment bed and the gantry so that the radiation beam emitted by the treatment head is focused on the target area from different incident angles includes: Controlling the treatment bed to swing in a horizontal plane so that the radiation beam emitted by the treatment head can be focused on the target area from different incident angles; Alternatively, the frame is controlled to swing in a horizontal plane so that the radiation beam emitted by the treatment head is focused on the target area from different incident angles.

20. A control method for a composite collimator, characterized in that: Used to control the composite collimator according to any one of claims 1 to 10, the method comprising: Acquiring irradiation information of a target object; When it is determined according to the irradiation information that the target object is irradiated with a focused radiation field, the collimation channel of the collimator and the grating channel of the first blade group are controlled to be located at the central axis of the beam, so that the radiation beam emitted by the radiation source forms the focused radiation field in the target area after passing through the collimation channel and the grating channel; When it is determined according to the irradiation information that the target object is irradiated with a conformal field, the collimation channel is controlled to deviate from the beam center axis so that the radiation beam emitted by the radiation source forms the conformal field through the grating channel formed by the first blade group and the grating channel formed by the second blade group.

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