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, and relates to the technical field of radiotherapy, and the composite collimator comprises a grating and a diaphragm which are sequentially arranged in the direction of a beam center axis, the plurality of blades move to form a grating channel through which a radiation beam can pass; the diaphragm is provided with a collimation channel, and the diaphragm can move relative to a beam center axis; when the diaphragm moves to enable the collimation channel to be located at the central axis of the beam, the radiation beam forms a focusing radiation field in a target area through the grating channel and the collimation channel; and when the diaphragm moves to enable the collimation channel to deviate from the beam center axis, the radiation beam forms a conformal radiation field in the target area through the grating channel. Through switching between the conformal radiation field and the focusing radiation field, a flexible irradiation scheme is provided, so that the dose distribution effect can be improved, and the radiotherapy effect is improved.

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] Multileaf grating systems are widely used in radiation medical technology, mainly based on the shielding effect of tungsten alloy on radioactive substances, and are specifically used to conform the irradiation field of large body tumors. In current clinical applications, SBRT (stereotactic radiotherapy) is usually used when the tumor size is less than 5cm. SBRT belongs to a small radiation field range and requires high precision. In this case, if traditional grating leaf conformal is used, the accuracy is difficult to meet the requirements. Affected by the resolution and penumbra, the shape and dose accuracy of the small radiation field are difficult to guarantee, which reduces the treatment effect. Summary of the invention

[0003] 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 clinical treatment accuracy and treatment effect.

[0004] 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 grating and an aperture sequentially arranged along the central axis of the beam; wherein the grating comprises 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 arranged on the aperture, and the aperture can move relative to the central axis of the beam; when the aperture moves so that the collimation channel is located on the central axis of the beam, the radiation beam forms a focused field in a target area through the grating channel and the collimation channel; when the aperture 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.

[0005] An embodiment of the present application also provides a radiotherapy system, including a treatment bed, a gantry and a treatment head, wherein the treatment head is arranged on the gantry, and the treatment bed is used to enter the gantry for treatment; wherein the treatment head includes a radiation source and the aforementioned composite collimator 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.

[0006] 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:

[0007] Obtain treatment plan information for the target subject;

[0008] The compound collimator of the treatment head is controlled according to the treatment plan so that the radiation beam guided to the target area passes through the collimation channel and the grating channel of the aperture, or the radiation beam only passes through the grating channel.

[0009] 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:

[0010] Acquiring irradiation information of a target object;

[0011] When it is determined according to the irradiation information that the target object is irradiated with a focused radiation field, the collimation channel and the grating channel of the control aperture are 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;

[0012] When it is determined according to the irradiation information that the target object is irradiated with a conformal radiation 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 radiation field through the grating channel.

[0013] 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 includes a device for shaping the radiation beam emitted by the radiation source, including: a grating and an aperture sequentially arranged along the central axis of the beam, wherein the grating includes a plurality of blades, and the movement of the plurality of blades forms a grating channel through which the radiation beam can pass; a collimation channel is arranged on the aperture, and the aperture can move relative to the central axis of the beam; when the aperture moves so that the collimation channel is located on 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; when the aperture 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. By switching between conformal fields and focused fields, a flexible irradiation scheme is provided, thereby improving the dose distribution effect and enhancing the radiotherapy effect.

[0014] 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.

[0015] 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

[0016] 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.

[0017] Figure 1 is a simplified schematic diagram of the radiotherapy system provided in this embodiment;

[0018] Figure 2is a simplified schematic diagram of the radiotherapy system provided in this embodiment;

[0019] Figure 3 is a simplified schematic diagram of the radiotherapy system provided in this embodiment;

[0020] Figure 4 is a schematic diagram of the composite collimator provided in this embodiment in an open source position;

[0021] Figure 5 is a schematic diagram of the composite collimator provided in this embodiment in the source-off position;

[0022] Figure 6 is a schematic diagram of the grating structure of the composite collimator provided in this embodiment;

[0023] Figure 7 is a corresponding relationship diagram between the aperture channel and the collimation channel of the composite collimator provided in this embodiment;

[0024] Figure 8 is a corresponding relationship diagram between the aperture channel and the collimation channel of the composite collimator provided in this embodiment;

[0025] Fig. 9 is a corresponding relationship diagram between the aperture channel and the collimation channel of the composite collimator provided in this embodiment;

[0026] Fig.10 is a corresponding relationship diagram between the aperture channel and the collimation channel of the composite collimator provided in this embodiment;

[0027] Fig.11 is a corresponding relationship diagram between the aperture channel and the collimation channel of the composite collimator provided in this embodiment;

[0028] Fig.12 yes Figure 4 Rotated cross-sectional view of

[0029] Fig.13 yes Fig.12 Another embodiment diagram of the present invention;

[0030] Fig.14 is a field forming principle diagram of the composite collimator provided in this embodiment;

[0031] Fig.15 is a field forming principle diagram of the composite collimator provided in this embodiment;

[0032] Fig.16 is a schematic diagram of the composite collimator provided in this embodiment in the source-off position;

[0033] Fig.17 is a schematic diagram of the composite collimator provided in this embodiment in an open source position;

[0034] Fig.18is a schematic diagram of the composite collimator provided in this embodiment in the source-off position;

[0035] Fig.19 yes Fig.17 Rotated cross-sectional view of

[0036] Fig. 20 yes Fig.19 Another embodiment diagram of the present invention;

[0037] Fig.21 is a schematic diagram of the swing of the treatment bed of the radiotherapy system provided in this embodiment;

[0038] Fig. 22 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0039] Fig.23 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0040] Fig.24 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0041] Fig.25 is a schematic diagram of the structure of the radiotherapy system provided in this embodiment;

[0042] Fig.26 is a schematic diagram of the swing of the gantry of the radiotherapy system provided in this embodiment;

[0043] Fig. 27 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0044] Fig.28 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0045] Fig.29 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0046] Fig.30 is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment;

[0047] Fig.31 It is a schematic diagram of the local structure of the radiotherapy system provided in this embodiment.

[0048] Icons: 10-radiation source; 10a-radiation beam; 12-grating; 12.1-blade; 12a-grating channel; 13-aperture; 13.1-aperture body; 13.2-collimator; 13a-collimator channel; 13b-aperture channel; 131-first aperture group; 132-second aperture group; 100A-radiation delivery device; 100-gantry; 100a-treatment space; 100b-gantry rotation axis; 101-housing; 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 gantry 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 gantry;Ff-focused radiation field;Fc-conformal radiation field;F1-first direction;F2-second direction. DETAILED DESCRIPTION

[0049] 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.

[0050] 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.

[0051] 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.

[0052] Radiotherapy refers to local treatment with radiation to eliminate and cure the primary or metastatic lesions of local tumors.

[0053] 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.

[0054] 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.

[0055] 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 ).

[0056] 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 .

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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 .

[0063] 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.

[0064] 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 the like, or a combination thereof.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] When performing radiation field irradiation, generally, large body tumors are irradiated with conformal radiation field Fc, but small tumors are irradiated with focused radiation field Ff for higher accuracy. In order to provide a more flexible radiation scheme for clinical applications, the composite collimator provided in the embodiment of the present application can achieve seamless switching between different radiation fields. In addition, the focused radiation source can also be used for local dose enhancement of tumors.

[0069] For example, the present application provides a composite collimator for shaping a radiation beam emitted by a radiation source, including: a grating and an aperture sequentially arranged along the central axis of the beam, wherein the grating includes 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 arranged on the aperture, and the aperture can move relative to the central axis of the beam; when the aperture moves so that the collimation channel is located on 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; when the aperture 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. By switching between conformal fields and focused fields, a flexible irradiation scheme is provided, thereby improving the dose distribution effect and enhancing the radiotherapy effect.

[0070] For examples, please refer to Figure 4 — Figure 7 As shown, an embodiment of the present application provides a composite collimator for shaping a radiation beam 10a emitted by a radiation source 10. The composite collimator includes: a grating 12 and an aperture 13 sequentially arranged along the central axis of the beam. The radiation beam 10a emitted by the radiation source 10 is shaped into a preset field after passing through the grating 12 and the aperture 13.

[0071] Among them, Figure 6 As shown, the grating 12 includes a plurality of blades 12.1, and the plurality of blades 12.1 move to form a grating channel 12a through which the radiation beam 10a can pass, and a complex shape and an approximately circular field can be envelop by the movement of the blades 12.1. For example, the grating includes blades, a drive, etc., and the specific structure of the grating is not described in detail in this application.

[0072] For example, Figure 4-Figure 5 As shown, the diaphragm 13 is provided with a collimation channel 13a, and the diaphragm 13 can move along the first direction F1; when the diaphragm 13 moves so that the collimation channel 13a is located at the central axis of the beam, the radiation beam 10a forms a focused field Ff in the target area through the grating channel 12a and the collimation channel 13a; when the diaphragm 13 moves so that the collimation channel 13a deviates from the central axis of the beam, the radiation beam 10a forms a conformal field Fc in the target area through the grating channel 12a. For example, the second direction F2 is perpendicular to the blade movement direction, and the first direction F1 is parallel to the blade movement. For example, the diaphragm can also move along the second direction F2.

[0073] In the embodiments provided by the present application, the translation direction of the aperture body is parallel to the movement direction of the blades of the grating, or the translation direction of the aperture body is perpendicular to the movement direction of the blades of the grating; or the movement direction of the collimator is parallel to the movement direction of the blades of the grating, or the movement direction of the collimator is perpendicular to the movement direction of the blades of the grating. Figure 8As shown, the translation direction of the aperture body is perpendicular to the movement direction of the blades of the grating. The movement direction of the collimator is perpendicular to the movement direction of the blades of the grating.

[0074] The composite collimator provided in the present application forms a field through the grating 12 and the aperture 13. For complex large field lesions, the radiation beam 10a can pass through the grating channel 12a, and the grating 12 is mainly used to form a complex large field (conformal field Fc), while the aperture 13 mainly follows the edge of the complex large field to block the radiation leakage outside the field. When it is necessary to use a precise small field to carry out SBRT / SRS treatment or to enhance the local dose of the tumor, the grating 12 is used to form a quasi-circular channel, and the corresponding collimation channel 13a on the aperture 13 moves to the central axis of the beam to form a beam channel together. The radiation beam 10a passes through the grating channel 12a and the collimation channel 13a of the aperture 13 to form a focused field Ff.

[0075] The composite collimator provided in the present application enables the movement of the aperture 13 so that the collimation channel 13a of the aperture 13 moves to the central axis of the beam to cooperate with the grating channel 12a to realize the focused field Ff, or enables the collimation channel 13a of the aperture 13 to deviate from the central axis of the beam and realize the conformal field Fc only through the grating channel 12a. By switching between the conformal field Fc and the focused field Ff, a flexible irradiation scheme is provided, thereby improving the dose distribution effect and enhancing the radiotherapy effect.

[0076] It should be noted that the order in which the radiation beam 10a passes through the grating 12 and the aperture 13 is not limited. For example, Figure 12-13 As shown, the aperture 13 is close to the radiation source 10, and the radiation beam 10a first passes through the aperture 13 and then passes through the grating 12. Alternatively, when the grating is close to the radiation source, the radiation beam first passes through the grating and then passes through the aperture. It should be noted that Figure 12-13 The order of the grating and aperture is not limited to rotate the cross-sectional view for clearer illustration.

[0077] In the embodiments provided in the present application, the aperture includes an aperture body and a collimator disposed on the aperture body and movable relative to the aperture body, the aperture body is used to drive the collimator to translate, the collimator channel is disposed on the collimator, and the aperture body is provided with an aperture channel coaxially corresponding to the collimator channel; through the translation of the aperture body and the movement of the collimator, the collimator channel and the aperture channel deviate from the beam center axis or the collimator channel and the aperture channel are located on the beam center axis.

[0078] In the embodiments of the present application, there are multiple implementation methods for making the collimation channel, the aperture channel deviate from the beam center axis or the collimation channel, or the aperture channel be located on the beam center axis through the translation of the aperture body and the movement of the collimator. For example, the movement of the collimator may be the rotation of the collimator, and / or the translation of the collimator. For example, the collimator may be a cylinder or a cuboid, and different collimation channels are arranged on the collimator, and the collimator may switch the collimation channels by rotation. The aperture may be arranged with one aperture channel or multiple aperture channels. The coordination of the various different movement modes of the aperture and the collimator makes the collimation channel, the aperture channel deviate from the beam center axis or the collimation channel, or the aperture channel be located on the beam center axis.

[0079] For example, Figure 7-Figure 8 As shown, in a first implementation, the aperture 13 includes an aperture body 13.1 and a collimator 13.2 disposed on the aperture body 13.1 and movable relative to the aperture body 13.1, the aperture body 13.1 is used to drive the collimator 13.2 to translate along a first direction F1, the collimator channel 13a is disposed on the collimator 13.2, and the aperture body 13.1 is provided with an aperture channel 13b for coaxially corresponding to the collimator channel 13a; for example, the aperture channel 13b corresponds to the collimator channel 13a, and the aperture of the aperture channel 13b is larger than the aperture of the collimator channel 13a; as shown in FIG. Fig. 9 As shown, when the aperture body 13.1 and the collimator 13.2 have substantially the same size along the beam center axis, the aperture channel 13b is substantially close to zero, as shown in FIG. Figure 4-Figure 5 As shown, the aperture channel is basically invisible.

[0080] like Figure 7-Figure 8 As shown, for example, the collimator can be cylindrical, and the collimator 13.2 can perform translation and rotational motion along the central axis of the beam. Figure 7 or Figure 4 As shown, when the collimator 13.2 rotates so that the aperture channel 13b corresponds to the collimator channel 13a, the collimator channel is opened. Figure 5 As shown, the collimation channel is closed and rays cannot pass through the collimation channel 13a. For example, the collimation channel can also be translated to make the collimation channel non-coaxial with the aperture channel, for example, the collimation channel is shielded by the aperture, thereby achieving the closing of the collimation channel.

[0081] For example, Figure 8 As shown, the collimator 13.2 is provided with a plurality of collimator channels of different sizes. The collimator 13.2 is translated along the second direction F2 so that different collimator channels 13a correspond to the aperture channels 13b, thereby switching collimator channels of different sizes as needed. For example, the collimator 13.2 can also be translated along the first direction F1 so that different collimator channels 13a correspond to the aperture channels 13b. Figure 8 The example shown is used as an example for explanation.

[0082] For example, Fig.10 As shown, the aperture body 13.1 may be provided with a plurality of aperture channels 13b, and the collimator 13.2 may be provided with a plurality of collimator channels 13a, and the plurality of collimator channels correspond to the plurality of aperture channels. Then, different collimator channels may be switched to be located on the beam axis by moving the aperture, so that the collimator 13.2 only rotates to switch the collimator channels, that is, the collimator channels are parallel to or intersecting (for example, perpendicular to) the beam axis.

[0083] For example, in the embodiment provided by the present application, the collimator may not be a cylinder, for example, the collimator may be a rectangle, and the switching of the collimation channel may be realized by translation of the collimator. In addition, the collimator may also be translated so that the collimation channel is shielded by the aperture body to realize the closing of the collimation channel.

[0084] For example, the present application provides a collimator, which can also be a spherical structure with a plurality of collimation channels passing through the center of the sphere formed thereon. Different collimation channels can correspond to the central axis of the beam by rotation.

[0085] For example, Figure 7-10 In the illustrated embodiment, the aperture moves along the second direction F2, and the collimator moves along the second direction F2, wherein the first direction F1 is the movement direction of the blades, that is, the movement direction of the aperture is the same as the movement direction of the blades. The embodiment of the present application does not limit the relationship between the aperture direction, the blade movement direction, and the collimator movement direction. For example, the movement direction of the aperture may be different from the blade movement direction, such as the aperture moving along the second direction F2. For another example, the movement direction of the collimator may be along the first direction F1 or the second direction F2. For example, Fig.11 As shown, the collimator movement direction may also be the first direction F1. Figure 7-Figure 11 The example shown is used as an example for explanation.

[0086] In the embodiment provided by the present application, the aperture body 13.1 and the collimator 13.2 are arranged along the central axis of the beam, the aperture channel 13b is formed on the aperture body 13.1, and the collimator 13.2 is formed on the collimator 13.2. The aperture body 13.1 can translate along the central axis of the beam, and the collimator 13.2 can translate and rotate along the central axis of the beam. For example, when the aperture body 13.1 translates, the collimator 13.2 is translated; when the collimator 13.2 moves, the aperture body 13.1 does not move accordingly.

[0087] In the embodiment provided in the present application, a plurality of collimation channels are provided on the collimator, and the aperture sizes of the plurality of collimation channels are different. When the collimation channels of different sizes move to the central axis of the beam, focusing fields Ff of different sizes can be formed. For example, the aperture size of the collimation channel 13a is generally less than 30cm. For example, the aperture size of the collimation 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.

[0088] Fig.12 An example is shown in which the radiation beam 10a passes through the aperture channel, the collimation channel and the grating channel in sequence. Fig.13 It shows that the radiation beam passes through the grating channel, the aperture channel, and the collimation channel in sequence.

[0089] In the embodiment provided in the present application, the aperture includes two apertures arranged opposite to each other, such as Figure 12-13 As shown, the aperture 13 on the left participates in the field formation, and the collimation channel 13a thereon is located at the open source position, while the aperture 13 on the right does not participate in the field formation, and the collimation channel 13a thereon is located at the closed source position. Figure 12-13 The radiation beam 10a forms a focused radiation field Ff in the target area. Fig.12 and Fig.13 Can be Figure 4 and Figure 5 Rotated section view of the diaphragm to better see the paired apertures.

[0090] In the embodiments provided in the present application, the grating and the aperture form a field together, and both the grating and the aperture can be independently controlled. The aperture is usually a pair, and the aperture includes two aperture components arranged opposite to each other, wherein at least one of the two aperture components is provided with a collimation channel, or the two aperture components are respectively provided with collimation channels.

[0091] Each aperture assembly includes an aperture body and a collimator, and the configuration thereof is referred to above and will not be described in detail. When only one aperture assembly is provided with a collimator channel, the collimator channel is moved so as to be located at the central axis of the beam or deviate from the central axis of the beam. When both aperture assemblies are provided with collimator channels, only one aperture assembly participates in field formation, and the collimator channel of the aperture assembly participating in field formation is located at the central axis of the beam.

[0092] In one embodiment provided in the present application, two aperture assemblies are provided with collimation channels respectively, for example, Fig.14 As shown, the collimation channel of one aperture assembly is larger than the collimation channel of the other aperture assembly, so that a variety of collimation channels of different sizes are distributed on the two aperture assemblies for selection. That is, the minimum collimation channel of one aperture is larger than the maximum collimation channel of the other aperture, so as to achieve rapid switching between approximate collimation channels.

[0093] When collimation channels are respectively arranged on two aperture assemblies, and the collimation channel of one aperture assembly is located at the beam center axis, the collimation channel of the other aperture assembly intersects with the beam center axis, thereby preventing the radiation beam from leaking from the collimation channel.

[0094] In one embodiment provided by the present application, an aperture component whose collimation channel is located on the central axis of the beam participates in the field formation, and another aperture component does not participate in the field formation, and in order to prevent the radiation beam from being scattered to the collimation channel of the aperture component that does not participate in the field formation, the collimation channel of the aperture component that does not participate in the field formation needs to be rotated to a position intersecting with the central axis of the beam to prevent the rays from passing through the collimation channel; preferably, when the collimation channel of the aperture component is rotated to be perpendicular to the central axis of the beam, the aperture component that does not participate in the field formation has a better effect of shielding the radiation beam. For example, the aperture component can be moved to prevent the rays from passing through the collimation channel, or the collimator can be rotated to prevent the rays from passing through the collimation channel, that is, the collimation channel on the collimator is closed.

[0095] The collimator is installed on the aperture body, and the collimator can move relative to the aperture body to realize the opening and closing of the collimation channel. The aperture moves as a whole, and the selected collimation channel is moved to the central axis of the beam. The collimator is located at the open source position. After the radiation beam passes through the grating channel and the collimation channel, it can form the required precise focusing field of view Ff shape on the isocenter plane, such as Figure 4 When the collimation channel moves away from the central axis of the beam, the collimator is in the closed source position, and the radiation beam passes through the grating channel to form a conformal field Fc on the isocenter plane. The aperture moves to the outside of the central axis of the beam, mainly following the edge of the complex field to block the radiation leakage outside the field, as shown in Figure 5 shown.

[0096] For example, Fig.14 As shown in FIG. 1 , when a focused field Ff needs to be formed, the selected collimation channel is positioned to the central axis of the beam through the reciprocating motion of the aperture, and the aperture and grating are both blocked at the edge of the precise focused field Ff to reduce the radiation leakage outside the field; as shown in FIG. Fig.15 As shown, when a conformal radiation field Fc is required, the aperture moves back and forth to reach the avoidance position, and the conformal radiation field Fc is formed by the grating, and the aperture follows the edge of the grating conformal radiation field Fc to block.

[0097] Another embodiment provided by this application, please refer to Figure 16-Figure 18 As shown, the aperture 13 includes a first aperture group 131 and a second aperture group 132 which are orthogonally arranged and can be translated, and a collimating channel 13a is formed on the first aperture group 131; the collimating channel 13a is deviated from the central axis of the beam or located on the central axis of the beam by the translation of the first aperture group 131, and the second aperture group 132 is used to block the edge gap of the grating channel 12a.

[0098] Each aperture group includes two apertures 13 arranged relative to the central axis of the beam, and the two aperture groups move orthogonally, and the two apertures 13 of each aperture group can be independently controlled to move; for example, Figure 16-Figure 18 As shown, the translation direction of the first aperture group 131 is parallel to the blade movement direction of the grating 12. Alternatively, the translation direction of the second aperture group 132 is the same as the blade movement direction of the grating 12.

[0099] For example, when the translation direction of the first aperture group 131 is parallel to the blade movement direction of the grating 12, the translation direction of the second aperture group 132 is perpendicular to the blade movement direction of the grating 12. In the embodiment of the present application, the second aperture group 132, whose blade movement direction is perpendicular, is slightly thinner, and its thickness is less than that of the first aperture group 131. The second aperture group 132 is mainly used to block the leakage rays of the gaps at the ends of the blades.

[0100] The first aperture group 131 that follows the movement of the blades is preset with a collimation channel 13a. The first aperture group 131 moves independently to position the selected collimation channel 13a to the central axis of the beam. There can also be multiple collimation channels 13a, and the aperture sizes of the multiple collimation channels 13a are different. When the first aperture group 131 is translated, different collimation channels 13a correspond to the central axis of the beam.

[0101] like Fig.17 As shown in the figure, when it is necessary to form a precise focusing field Ff, the thin aperture group retreats to the outermost side, and the aperture group with the collimation channel moves to position the selected collimation channel on the central axis of the beam; in coordination with the grating, the grating blades move to envelop a quasi-circular / conical collimation channel. Fig.16 As shown in FIG. 1 , when a conformal radiation field Fc is required, both aperture groups are withdrawn to the outside, the collimation channel deviates from the central axis of the beam, and the radiation beam only passes through the grating channel to form a conformal radiation field Fc. At this time, the two aperture groups can be used to shield the leakage of the blades.

[0102] For example, Figure 16-Figure 18 As shown, the first aperture group 131 and the second aperture group 132 respectively include two apertures, and the two apertures of the same aperture group are arranged opposite to each other. For example, the aperture group with a collimating channel includes two apertures, and the two apertures are respectively provided with a plurality of collimating channels, and the sizes of the plurality of collimating channels are different. For example, the maximum collimating channel aperture on one of the apertures is smaller than the minimum collimating channel aperture on the other aperture. For example, when the collimating channel is conical, the conical collimating channel focuses on the target.

[0103] The present application does not limit the position order of the aperture and the grating. For example, Fig.19 As shown, the radiation beam 10a first passes through the collimating channel 13a of one of the apertures 13 and then passes through the grating channel 12a; or as shown in FIG. Fig. 20In the embodiment, the radiation beam 10a first passes through the grating channel 12a and then passes through the collimating channel 13a of one of the apertures 13.

[0104] In the embodiment of the present application, the aperture group that follows the movement of the blades mainly blocks the radiation leakage between the blades. A collimation channel is preset. When it is not in the working position, the collimation channel is not parallel to the beam direction, and the radiation beam is blocked and will not penetrate directly, which does not affect the enhanced protection of the trace radiation leakage between the blades. Only when the collimation channel is in the working position, the radiation beam can pass through the collimation channel.

[0105] In the embodiment provided in the present application, for example, the first aperture group 131 and the second aperture group 132 are located in the same plane, so that the structure is compact and the overall axial size is small. Alternatively, the first aperture group 131 and the second aperture group 132 may also be located in different planes.

[0106] Through the above embodiments, the purpose of moving the collimating channel to or away from the beam center axis is achieved. The present application does not specifically limit the shape of the collimating channel, and the collimating channel can be a cylindrical channel, a conical channel or other channels.

[0107] Generally, the collimation channel is a conical channel, which can constrain the radiation beam generated by the radiation source to a precise shape, usually a circle, on the isocenter plane. When it is a conical channel, optionally, the cross-sectional size of the end of the conical channel close to the radiation source is smaller than the cross-sectional size of the end of the conical channel away from the radiation source.

[0108] For example, the aperture channel, grating channel and collimation channel are coaxial, and the non-coplanar irradiation conical channels are focused on the target (which can be an accelerator target or a gamma knife radiation source), with a small penumbra, high field accuracy, continuous and smooth field edges, and precise dimensions.

[0109] The above-mentioned composite collimator can realize switching between different radiation fields; when the above-mentioned composite collimator is applied to the radiotherapy system of the present application, it can be used as a conventional conformal intensity modulated collimator, and can also form a precise radiation field shape to realize precise SRS / SBRT treatment.

[0110] 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.

[0111] In one embodiment of the present application, Fig.21 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.

[0112] For details, please refer to Figure 22-Figure 23 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.

[0113] 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.

[0114] For example, the center of the first arc guide rail 111 a is coaxial with the isocenter O of the radiotherapy system.

[0115] Another embodiment provided by the present application is as follows: Fig.24 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.

[0116] 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.

[0117] 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.

[0118] like Fig.25 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.

[0119] 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.

[0120] 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.

[0121] 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.

[0122] Therefore, in another embodiment of the present application, reference Figure 25-Figure 29 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.

[0123] 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.

[0124] For examples, please refer to Fig. 27 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.31 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.

[0125] For example, Fig. 27 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.

[0126] Among them, Figure 28-Figure 30 As 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.

[0127] 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.

[0128] For example, Fig.29 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.30 , 31 shown.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] 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.

[0134] 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.

[0135] 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:

[0136] S10: Obtaining irradiation information of the target object.

[0137] 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.

[0138] S11: When it is determined according to the irradiation information that the target object is irradiated with a focused field Ff, the collimation channel and the grating channel of the aperture 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.

[0139] For example, when focusing irradiation is used, the movement of the aperture can be controlled so that the collimation channel of the aperture is located on the central axis of the beam; the movement of the blades of the grating can be controlled so that the grating channel of the grating is located on the central axis of the beam; finally, the compound collimator is controlled so that the radiation beam guided to the target area passes through the collimation channel and the grating channel of the aperture, thereby forming a focused field Ff in the target area.

[0140] S12: When it is determined according to the irradiation information that the target object is irradiated with the conformal field Fc, 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 the conformal field Fc through the grating channel.

[0141] For example, when using a conformal field Fc, the movement of the aperture is controlled so that the collimation channel of the aperture deviates from the central axis of the beam; the movement of the blades of the grating is controlled so that the grating channel of the grating is located on the central axis of the beam, that is, the central axis of the beam passes through the grating channel; the radiation beam passes through the grating channel to form a conformal field Fc in the target area.

[0142] Through the above control method, the grating and the aperture are controlled according to different irradiation information to generate the required focused field Ff or conformal field Fc. The whole process is simple and efficient.

[0143] 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:

[0144] S20: Obtain treatment plan information of the target object.

[0145] 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.

[0146] 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.

[0147] S21: Control the compound collimator of the treatment head according to the treatment plan so that the radiation beam guided to the target area passes through the collimation channel and the grating channel of the aperture, or the radiation beam only passes through the grating channel.

[0148] When the radiation beam passes through the collimation channel and the grating channel, a precise focused radiation field Ff can be formed; when the radiation beam only passes through the grating channel, a conformal radiation field can be formed. That is, the field formation method is selected according to the above treatment plan information.

[0149] For example, in an optional embodiment of the present application, the dose delivery method of the radiotherapy system further includes:

[0150] The relative swing between the treatment bed and the frame is controlled so that the angle between the treatment bed and the frame is different. Through the relative swing between the treatment bed and the frame, coplanar irradiation or non-coplanar irradiation can be achieved to meet different treatment needs.

[0151] 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.

[0152] 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.

[0153] For the relative swinging manner between the treatment bed 200 and the frame 100, please refer to the above description for details.

[0154] Different radiation fields (conformal radiation field Fc or focused radiation field Ff) can be selected according to the patient's lesions. The two conformal modes can be quickly switched. The patient can be positioned once and two radiation modes 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.

[0155] When the two fields of view are used in combination, the MLC-based conformal field Fc can be used for basic dose irradiation first, which has a large coverage area; for the core area of ​​the lesion, the focused field Ff combined with non-coplanar focused irradiation can be used to increase the dose in the target area and improve the cure rate of the tumor. For patients suitable for SBRT, the precise focused field Ff can be used in combination with non-coplanar focused irradiation. Of course, a composite collimator can also be used to carry out conventional MLC-based conformal field Fc intensity-modulated irradiation.

[0156] The present application embodiment provides a dose delivery method for a radiotherapy system, including S100-S110:

[0157] S100: driving the treatment couch 200 so that the patient is located in the treatment space 100a of the gantry 100.

[0158] The treatment couch 200 can be driven by the first treatment couch driving device to enter the treatment space 100a for treatment.

[0159] 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.

[0160] 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 .

[0161] Furthermore, the swing stability of the treatment bed 200 can be enhanced through the auxiliary effect of the second arc guide rail 201 .

[0162] By way of example, an embodiment of the present application provides a dose delivery method for a radiotherapy system, further comprising S120: via a compound collimator, a radiation beam 10a that is directed to a target area is formed into a focused field Ff or a conformal field Fc along a radiation source beam. By way of example, the compound collimator may be the compound collimator provided in the present application, which includes an aperture collimator (aperture 13) and a multi-leaf collimator (grating 12); the compound collimator is driven so that the radiation beam 10a that is directed to a target area passes through the aperture collimator to form a focused field Ff; the aforementioned aperture 13 and grating 12 form a field together, and the radiation beam 10a passes through the grating channel 12a and the collimation channel 13a to form a focused field Ff; or, the compound collimator is driven so that the radiation beam 10a that is directed to a target area passes through the multi-leaf collimator to form a conformal field Fc; the aperture 13 and grating 12 form a field together, and the radiation beam 10a passes through the grating channel 12a to form a conformal field Fc.

[0163] The specific method of driving the composite collimator can refer to the above embodiments of the present application and will not be described in detail here.

[0164] 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.

[0165] 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.

[0166] For example, the present application also provides a dose delivery method of a radiotherapy system, including S200-S210:

[0167] S200: driving the treatment couch 200 so that the patient is located in the treatment space 100a of the gantry 100.

[0168] 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.

[0169] 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.

[0170] 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 Ff or a conformal field Fc along a radiation source beam.

[0171] Likewise, compound collimators include aperture collimators and multi-leaf collimators, including:

[0172] Driving the compound collimator so that the radiation beam 10a directed to the target area passes through the aperture collimator to form a focused radiation field Ff;

[0173] Alternatively, the compound collimator is driven so that the radiation beam 10a directed to the target area passes through the multi-leaf collimator to form a conformal field Fc.

[0174] 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.

[0175] 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.

[0176] 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.

[0177] For example, in the embodiment provided by the present application, the two field modes can be flexibly switched. The conformal field Fc can be selected to efficiently perform basic dose irradiation, and then the precise focused field Ff can be used to irradiate the core area inside the target area, which is more in line with the dose distribution requirements of SBRT.

[0178] 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.

[0179] 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.

[0180] 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.

[0181] 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, including: gratings and apertures arranged in sequence along the central axis of the beam; Wherein, the grating comprises 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 aperture, and the aperture can move relative to the central axis of the beam; when the aperture 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; when the aperture 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.

2. The composite collimator according to claim 1, characterized in that: The aperture comprises an aperture body and a collimator disposed on the aperture body and movable relative to the aperture body, the aperture body is used to drive the collimator to translate, the collimator channel is disposed on the collimator, and the aperture body is provided with an aperture channel for being coaxially corresponding to the collimator channel; Through the translation of the aperture body and the movement of the collimating body, the collimating channel and the aperture channel are deviated from the beam center axis or the collimating channel and the aperture channel are located on the beam center axis.

3. The composite collimator according to claim 2, characterized in that: The collimator is cylindrical, and a plurality of collimator channels are arranged on the collimator, and the aperture sizes of the plurality of collimator channels are different.

4. The composite collimator according to claim 3, characterized in that: An aperture channel is arranged on the aperture body, and one aperture channel corresponds to each of the plurality of collimation channels; Alternatively, a plurality of the aperture channels are provided on the aperture body, and the plurality of the aperture channels correspond one-to-one to the plurality of the collimation channels.

5. The composite collimator according to claim 2, characterized in that: The collimating body rotates to make the collimating channel and the aperture channel coaxially correspond to each other, or to make the collimating channel deviate from the aperture channel.

6. The composite collimator according to claim 2, characterized in that: The translation direction of the aperture body is parallel to the movement direction of the blades of the grating, or the translation direction of the aperture body is perpendicular to the movement direction of the blades of the grating; or the movement direction of the collimator is parallel to the movement direction of the blades of the grating, or the movement direction of the collimator is perpendicular to the movement direction of the blades of the grating.

7. The composite collimator according to claim 2, characterized in that: When the collimation channel deviates from the beam center axis, the angle between the axis of the collimation channel and the beam center axis is 90°.

8. The composite collimator according to claim 2, characterized in that: The aperture comprises two aperture components arranged opposite to each other, wherein at least one of the two aperture components is provided with the collimating channel, or the two aperture components are respectively provided with the collimating channels.

9. The composite collimator according to claim 8, characterized in that: When the collimating channels are respectively arranged on the two aperture components, the collimating channel of one of the aperture components is larger than the collimating channel of the other aperture component.

10. The composite collimator according to claim 1, characterized in that: The aperture includes a first aperture group and a second aperture group which are orthogonally arranged and can be translated, and the collimation channel is formed on the first aperture group; the collimation channel is deviated from the beam center axis or located on the beam center axis by translation of the first aperture group, and the second aperture group is used to block the gap formed by the end of the grating blade.

11. The composite collimator according to claim 10, characterized in that: The translation direction of the first aperture group is parallel to the movement direction of the blades of the grating.

12. The composite collimator according to claim 10, characterized in that: The first aperture group and the second aperture group are located in the same plane, or the first aperture group and the second aperture group are located in different planes.

13. The composite collimator according to claim 10, characterized in that: There are a plurality of collimating channels, and the aperture sizes of the plurality of collimating channels are different. When the first aperture group is translated, different collimating channels correspond to the central axis of the beam.

14. The composite collimator according to any one of claims 1 to 13, 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.

15. 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 14 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.

16. The radiotherapy system according to claim 15, 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.

17. The radiotherapy system according to claim 16, characterized in that: The treatment bed is swingably arranged in a horizontal plane so that the angles between the treatment bed and the frame are different.

18. The radiotherapy system according to claim 16, characterized in that: The frame is swingably arranged in a horizontal plane so that the angles between the treatment bed and the frame are different.

19. The radiotherapy system according to claim 15, characterized in that: The radiotherapy system further comprises an image guidance system, and the image guidance system is arranged on the frame.

20. 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 15 to 19, 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 so that the radiation beam guided to the target area passes through the collimation channel and the grating channel of the aperture, or the radiation beam only passes through the grating channel.

21. The dose delivery method of the radiotherapy system according to claim 20, 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.

22. The dose delivery method of the radiotherapy system according to claim 21, 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; or, The frame is controlled 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.

23. A control method for a composite collimator, characterized in that: For controlling the composite collimator according to any one of claims 1 to 14, 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 field, the collimation channel and the grating channel of the control diaphragm are located at the central axis of the beam, so that the radiation beam emitted by the radiation source forms the focused 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.

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