Ion beam rapid scanning irradiation system

Abstract

The present application relates to a kind of ion beam fast scanning irradiation system, comprising: target area design module, for obtaining irradiation target area based on the pre-acquired 4DCT scanning and motion curve data and design requirement;Scan sequence generation module is used to generate treatment planning file according to irradiation target area, and the scan point weight distribution is optimized, and the scan point sequence corresponding to the energy fault of irradiation target area is obtained;Ion beam irradiation module is used to send the scan point sequence generated to accelerator treatment control system, and the corresponding ion beam flow is generated by accelerator treatment control system.The present application will evenly distribute the repeated scanning on motion phase, so that each phase (or in the motion phase of control window) can be effectively irradiated, ensure that target area is evenly covered with high dose, and can be widely applied in ion beam radiotherapy field.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of ion beam radiotherapy, and particularly relates to a kind of ion beam fast scanning irradiation system. BACKGROUND

[0002] Due to the reversed depth dose distribution (Bragg peak) characteristics, ion beams (protons, heavy ions, etc.) can improve the dose coverage of target regions while effectively protecting normal tissues in radiotherapy. In radiotherapy, the target region is usually outlined by a physician on a CT image, and a radiotherapy plan is designed. Before the implementation of beam irradiation, the isocenter of the target region is placed at the isocenter of the beam through the image-guided device in the treatment room, and it is assumed that the position of the target region remains unchanged during treatment, so that precise beam irradiation is implemented.

[0003] However, for moving target regions, even if accurate positioning is performed using image-guided devices before treatment, the target region is in motion during beam irradiation, resulting in a shift between the actual irradiation position and the irradiation position designed in the previous treatment plan, causing uneven dose distribution in the target region, the appearance of cold and hot spots, and affecting the effectiveness of irradiation. For moving target bodies, on the one hand, the movement of the target region will cause changes in tissue density along the ion beam path, resulting in changes in the range of the ion beam; on the other hand, the movement of the target region will cause a shift between the actual irradiation position and the preset position of the ion beam scanning point, resulting in severe distortion of the dose distribution in the target region, causing damage to the surrounding tissues, and seriously affecting the effectiveness of ion beam radiotherapy. Therefore, developing motion management techniques, improving the uniformity of target region dose distribution, reducing radiation damage to surrounding tissues, and fully utilizing the advantages of ion beam radiotherapy are difficult and hot topics in the field of ion beam radiotherapy internationally.

[0004] Currently, commonly used target motion management techniques internationally include increasing the target area's outer contour, respiratory gating, and random pause-repeated scanning. The main purpose of increasing the target area's outer contour is to include the entire range of motion of the target area within the irradiation field at all times, ensuring effective irradiation of the target area at every moment. However, ion beam radiotherapy typically employs a point-scan beam delivery method, dividing the target area into multiple iso-energy intervals along the beam direction, and then setting scanning points on each energy interval to achieve high-dose uniform coverage of the target area through point-by-point irradiation. Therefore, even with increased target area contour, target motion causes deviations between the actual irradiation position and the preset position of the scanning point, resulting in dose distribution distortion within the target area, thus failing to solve the problem of dose distribution distortion. Respiratory gating, by setting an appropriately sized gating window on the motion curve, reduces the amplitude of target area motion during beam irradiation, attempting to improve the dose distribution non-uniformity caused by motion. However, respiratory gating technology only reduces the amplitude of target motion during beam irradiation; it does not completely eliminate motion. Residual motion within the gating window can still cause distortion of the dose distribution in the ion beam radiation field. The random pause-repeated scanning method primarily divides a single irradiation at each energy tomographic scan point into multiple irradiations, setting a random pause between adjacent scans. This attempts to statistically eliminate cold and hot spots in the dose distribution within the target area through repeated scanning. However, this method, by setting random pauses between adjacent scans, leads to a significant increase in the overall irradiation time, requiring 15–20 or even more scans to achieve the desired effect, severely impacting the ion beam irradiation efficiency. Therefore, developing precise and efficient target motion management technology is an urgent problem to be solved in the field of ion beam radiotherapy. Summary of the Invention

[0005] To address the issues of poor irradiation accuracy and low efficiency in existing target motion management technologies, the present invention aims to provide an ion beam rapid scanning irradiation system. This system not only solves the problem of uneven dose distribution within the target area during ion beam irradiation, but also improves the irradiation efficiency of the ion beam while reducing the number of scans, thereby achieving precise and efficient ion beam radiotherapy for moving target areas.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] An ion beam rapid scanning irradiation system includes:

[0008] The target area design module is used to obtain the irradiation target area based on the pre-acquired 4DCT scan and motion curve data and design requirements;

[0009] a scan sequence generation module configured to generate a treatment plan file according to the irradiation target region and optimize the scan point weight distribution to obtain a scan point sequence corresponding to each energy slice of the irradiation target region;

[0010] an ion beam irradiation module configured to send the generated scan point sequence to an accelerator treatment control system to generate a corresponding ion beam flow by the accelerator treatment control system.

[0011] Further, the target region design module comprises:

[0012] a target region contouring module configured to reconstruct 3D CT image data of each motion phase based on 4D CT scanning and motion curve data and perform target region contouring on each motion phase;

[0013] an irradiation mode selection module configured to determine an irradiation mode according to a design requirement and calculate a geometric inner target region and a range inner target region based on the determined irradiation mode and the target region contour of each motion phase;

[0014] an irradiation target region determination module configured to correct the calculated geometric inner target region and range inner target region according to uncertainty factors to form an irradiation target region.

[0015] Further, the target region contouring module comprises:

[0016] an image data reconstruction module configured to reconstruct 3D CT image data of each motion phase based on the obtained 4D CT scanning data;

[0017] a reference phase target region contouring module configured to select a motion phase with a position repeatability meeting a preset requirement as a reference phase from the 3D CT image data and perform target region contouring on the reference phase;

[0018] a remaining phase target region contouring module configured to perform target region contouring on other remaining motion phases except the reference phase.

[0019] Further, when the remaining phase target region contouring module performs target region contouring on other remaining motion phases except the reference phase, a deformation registration method is used to deform the target region contour of the reference phase to other motion phases.

[0020] Further, when the irradiation mode selection module determines the irradiation mode according to the design requirement, the irradiation mode adopted comprises a gated treatment mode and a free motion mode;

[0021] When the free motion mode is adopted, the geometric inner target region is formed by taking the union of the target region contours of all motion phases; and the range inner target region is formed by calculating the change of the ion beam range caused by the change of the tissue density on different motion phases;

[0022] When the gating treatment mode is adopted, the geometric inner target region and the range inner target region are calculated by the motion phase within the gating window.

[0023] Further, the scan sequence generation module comprises:

[0024] a scan number setting module, configured to divide the scan point weight of each energy layer of the irradiation target region, so that the original single scan becomes m scans;

[0025] a free motion mode sequence generation module, configured to determine the scan time of the m scans corresponding to each energy layer of the irradiation target region in the free motion mode, and generate a scan point sequence in combination with the divided scan point weight;

[0026] a gating mode scan sequence generation module, configured to determine the scan time of the m scans corresponding to each energy layer of the irradiation target region in the gating mode, and generate a scan point sequence in combination with the divided scan point weight.

[0027] Further, in the scan number setting module, when the scan point weight of each energy layer of the irradiation target region is divided, the division method comprises:

[0028] proportionally dividing each scan point weight by the scan number m to obtain the division weight of each scan point;

[0029] or dividing each scan point weight by the amount of single scan to obtain the scan number.

[0030] Further, the free motion mode sequence generation module comprises:

[0031] a motion cycle calculation module, configured to calculate the average motion cycle t1 in the free motion mode; wherein the calculation method of the average motion cycle is known to those skilled in the art, and the present application does not limit this;

[0032] a first adjacent scan time interval calculation module, configured to divide the average motion cycle t1 into m parts according to the scan number, to obtain the first adjacent scan time interval t1 / m;

[0033] a first energy layer repeated scan module, configured to select a time as a scan starting time, obtain a plurality of scan times arranged at equal time intervals according to the first adjacent scan time interval, and allocate the first to m scans corresponding to the first energy layer of the irradiation target region to each scan time;

[0034] The first residual energy tomography repeated scanning module is configured to assign the first scanning to the mth scanning corresponding to each energy tomography to the corresponding scanning time point by using the same method as that of the first energy tomography repeated scanning module, so as to obtain a scanning point sequence.

[0035] Further, the gated mode scanning sequence generation module comprises:

[0036] The gated window calculation module is configured to calculate the size t2 of the gated window in the free motion plus gated mode.

[0037] The second adjacent scanning time interval calculation module is configured to divide the size of the gated window into m parts according to the scanning times, so as to obtain the second adjacent scanning time interval t2 / m.

[0038] The second initial energy tomography repeated scanning module is configured to select the start point of the gated window as the scanning start time point, and obtain a plurality of scanning time points arranged at equal time intervals according to the second adjacent scanning time interval, and assign the first scanning to the mth scanning corresponding to each energy tomography to each scanning time point.

[0039] The second residual energy tomography repeated scanning module is configured to assign the first scanning to the mth scanning corresponding to each energy tomography to the corresponding scanning point sequence by using the same method as that of the second initial energy tomography repeated scanning module.

[0040] The present application has the following advantages due to the above technical solutions:

[0041] (1) The present application uniformly distributes the repeated scanning on the motion phase, so that each phase (or motion phase within the gated window) can be effectively irradiated, and the target area is uniformly covered with high dose;

[0042] (2) The present application fully irradiates each breathing phase (or motion phase within the gated window), so that a uniform dose distribution can be achieved without too many scanning times, thereby improving the beam irradiation efficiency;

[0043] (3) The present application is suitable for regular target area motion and irregular target area motion, and has high robustness;

[0044] (4) The present application is simple in irradiation control, only needs to set the time interval between adjacent scans before treatment, has low requirements for the irradiation control system, and is convenient to operate;

[0045] Therefore, the present application can be widely applied in the field of ion beam radiotherapy. BRIEF DESCRIPTION OF DRAWINGS

[0046] Various other advantages and benefits will become apparent to those of ordinary skill in the art, upon reading the following detailed description of the preferred embodiments. The detailed description is made with reference to the accompanying drawings. The description is presented for purposes of illustration and description, but is not intended to limit the application. In the drawings:

[0047] Figure 1 is a schematic diagram of the ion beam fast scanning irradiation system provided by the embodiments of the present application;

[0048] Figure 2 is a schematic diagram of the ion beam fast scanning irradiation system provided by the embodiments of the present application;

[0049] Figures 3a-3d is a dose distribution diagram of the target body free movement under different numbers of single scanning and repeated scanning, wherein Figure 3a is a dose distribution diagram of single scanning; Figure 3b is a dose distribution diagram of repeated scanning 2 times; Figure 3c is a dose distribution diagram of repeated scanning 4 times; Figure 3d is a dose distribution diagram of repeated scanning 6 times;

[0050] The various reference signs in the drawings are as follows:

[0051] 1, target area movement signal; 2, gating threshold; 3, gating window; 4, 1st scanning of the nth energy layer; 5, 2nd scanning of the nth energy layer; 6, 3rd scanning of the nth energy layer; 7, 4th scanning of the nth energy layer; 8, other scanning (if any) of the nth energy layer; 9, 1st scanning of the (n+1)th energy layer; 10, 2nd scanning of the (n+1)th energy layer; 11, 3rd scanning of the (n+1)th energy layer; 12, 4th scanning of the (n+1)th energy layer; 13, other scanning (if any) of the (n+1)th energy layer. DETAILED DESCRIPTION

[0052] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the described embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.

[0053] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0054] In some embodiments of the present invention, an ion beam rapid scanning irradiation system is provided, which is designed to eliminate or compensate for the uneven dose distribution caused by the interaction between target movement and dynamic beam delivery process in ion beam radiotherapy, resulting in a deformation of dose distribution in the radiation field and a reduction in irradiation effect.

[0055] Example 1

[0056] like Figure 1 As shown, this embodiment provides an ion beam rapid scanning irradiation system, which includes: a target area design module, used to obtain the irradiation target area based on pre-acquired 4DCT scan and motion curve data and design requirements; a scan sequence generation module, used to generate a treatment plan file including irradiation field direction, scan point spacing, energy tomographic interval, scan point position distribution, scan point weight distribution, etc., according to the irradiation target area, and optimize the scan point weight distribution to obtain a scan point sequence corresponding to each energy tomographic segment of the irradiation target area; and an ion beam irradiation module, used to send the generated scan point sequence to the accelerator treatment control system, whereby the accelerator treatment control system generates a corresponding ion beam current for ion beam irradiation of the target.

[0057] Preferably, the target area design module includes: a target area contour drawing module, used to reconstruct 3DCT image data for each motion phase based on 4DCT scans and motion curve data, and to draw the target area contour for each motion phase; an irradiation mode selection module, used to determine the irradiation mode according to design requirements, and to calculate the geometrically inner target area and the target area within the firing range based on the determined irradiation mode and the target area contour for each motion phase; and an irradiation target area determination module, used to correct the calculated geometrically inner target area and the target area within the firing range according to uncertainty factors, forming the final planned target area, i.e., the irradiation target area. The uncertainty factors mainly include positioning errors, ion beam range errors, etc.

[0058] Preferably, the target volume contouring module comprises: an image data reconstruction module, configured to reconstruct 3D CT image data of each motion phase based on the acquired 4D CT scan data; a reference phase target volume contouring module, configured to select a motion phase with position repeatability meeting a preset requirement from the 3D CT image data as a reference phase, and to contour the target volume and the surrounding organ contour of the reference phase; and a remaining phase target volume contouring module, configured to contour the target volume of the remaining motion phases other than the reference phase. When contouring the target volume of the remaining motion phases other than the reference phase, the contouring of the target volume can be performed manually, or the target volume contour of the reference phase can be deformed to other motion phases by using a deformation registration method.

[0059] Preferably, when the irradiation mode selection module determines the irradiation mode according to the design requirements, the irradiation mode adopted comprises a gated treatment mode and a free motion mode. When the free motion mode is adopted, the geometric inner target volume is formed by taking the union of the target volume contours of all motion phases; the range inner target volume is formed by calculating the change of the ion beam range caused by the change of the tissue density on different motion phases; and when the gated treatment mode is adopted, the calculation of the geometric inner target volume and the range inner target volume is performed by using the motion phases within the gating window.

[0060] Preferably, the scan sequence generation module comprises: a scan number setting module, configured to divide the scan point weight of each energy slice of the irradiation target volume, so that the original single scan becomes m scans; a free motion mode sequence generation module, configured to determine the scan time of the m scans corresponding to each energy slice of the irradiation target volume in the free motion mode, and to generate a scan point sequence in combination with the divided scan point weight; and a gated mode scan sequence generation module, configured to determine the scan time of the m scans corresponding to each energy slice of the irradiation target volume in the gated mode, and to generate a scan point sequence in combination with the divided scan point weight.

[0061] When the scan point weight of each energy slice of the irradiation target volume is divided based on the scan number m, the division manner comprises: proportional division, i.e. each scan point weight is divided by the scan number m; or fixed single scan amount, i.e. each scan point is divided according to its weight, and the scan point with a large weight is divided into a large number of times, and the scan point with a small weight is divided into a small number of times.

[0062] Preferably, the free motion mode sequence generation module comprises:

[0063] A motion cycle calculation module, configured to calculate the average motion cycle t1 in the free motion mode; wherein the calculation method of the average motion cycle is known to those skilled in the art, and the present application does not limit this;

[0064] a first adjacent scanning time interval calculation module, configured to divide the average motion cycle t1 into m parts according to the number of scans, to obtain a first adjacent scanning time interval t1 / m;

[0065] a first energy layer repeated scanning module, configured to select a time point as a scanning starting time point, to obtain a plurality of scanning time points arranged at equal time intervals according to the first adjacent scanning time interval, and to allocate the first scan to the mth scan corresponding to the first energy layer of the target region to each scanning time point; in particular, if a single scan cannot be completed within the first adjacent scanning time interval t1 / m time period, the next scan is directly started from the end time point of the current scan. That is, when the time required for a single scan is greater than the first adjacent scanning time interval t1 / m, the scanning interval is no longer set, and the scans are performed continuously.

[0066] a first remaining energy layer repeated scanning module, configured to allocate the first scan to the mth scan corresponding to each of the other energy layers to the corresponding scanning time point by using the same method as the first energy layer repeated scanning module, to obtain a scanning point sequence.

[0067] Preferably, the gated mode scan sequence generation module comprises:

[0068] a gating window calculation module, configured to calculate the size t2 of the gating window in the free motion plus gated mode;

[0069] a second adjacent scanning time interval calculation module, configured to divide the size of the gating window into m parts according to the number of scans, to obtain a second adjacent scanning time interval t2 / m;

[0070] a second initial energy layer repeated scanning module, configured to select the starting point of the gating window as the scanning starting time point, to obtain a plurality of scanning time points arranged at equal time intervals according to the second adjacent scanning time interval, and to allocate the first scan to the mth scan corresponding to the first energy layer of the target region to each scanning time point; wherein if a single scan cannot be completed within the t2 / m time period, the next scan is directly started from the end time point of the current scan;

[0071] a second remaining energy layer repeated scanning module, configured to allocate the first scan to the mth scan corresponding to each of the other energy layers to the corresponding scanning point sequence by using the same method as the second initial energy layer repeated scanning module.

[0072] Preferably, if the target region motion is irregular (for example, the motion cycle changes), for the free motion without gating, the irradiation mode does not change, and each scan of each energy slice is irradiated at equal time intervals; for the free motion with gating mode, the irradiation starts from the first scan of the first energy slice of the target region at the start time of the scan, and the other scans of the first energy slice are irradiated at equal time intervals, if the current gating window cannot complete the scan of the current energy slice, the remaining scan of the current energy slice is continued in the next gating window, and after the scan is completed, each scan of the next energy slice is irradiated at equal time intervals, and so on, until all energy slices are irradiated.

[0073] Embodiment 2

[0074] As shown in Figure 2 , this embodiment is introduced in the mode of free motion with gating. Figure 2 In this embodiment, first, the size t of the gating window is calculated, the size of the gating window is divided into m parts, and the time interval t / m of each part is calculated; then, the start point of the gating window is selected as the start time t1 of irradiation, and the first scan of the first energy slice of the target region is assigned to the start time t1 for irradiation, the second scan time t2 of the first energy slice is t / m time from the start time, the third scan time t3 of the first energy slice is 2×t / m time from the start time, and so on, if a single scan cannot be completed within t / m time, the next scan is directly started from the end time of the current scan; when the first energy slice is irradiated, the second energy slice is irradiated, at this time the target region will move to the second gating window, and the method is consistent with the irradiation method of the first energy slice, until all energy slices are irradiated.

[0075] As shown in FIG. 3, it is a target region dose distribution diagram obtained by using the ion beam rapid scanning irradiation system of the present application. As can be seen, in the case of free motion single scan, the interaction between target region motion and dynamic beam distribution process causes the dose distribution to be severely deformed, and dose cold and hot spots occur, so that the effect of irradiation cannot be guaranteed. For rapid repeated scanning, the uniformity of the dose distribution gradually improves with the increase of the number of scans. Therefore, the ion beam rapid repeated scanning irradiation method can effectively irradiate each motion phase of the target region, and finally form a uniform high dose coverage in the target region; at the same time, compared with the traditional random pause repeated scanning method, the present application can achieve more uniform target region dose coverage while reducing the number of irradiations, and improve the efficiency of irradiation. Therefore, the present application can make the advantages of ion beam radiotherapy be fully played, further improve the curative effect of ion beam radiotherapy, and achieve the purpose of precise and efficient radiotherapy.

[0076] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An ion beam rapid scanning irradiation system, characterized by, The application relates to a target region design module for obtaining an irradiation target region based on pre-acquired 4DCT scanning and motion curve data and design requirements; a scanning sequence generation module for generating a treatment plan file according to the irradiation target region and optimizing scanning point weight distribution to obtain scanning point sequences corresponding to each energy layer of the irradiation target region; and an ion beam irradiation module for sending the generated scanning point sequences to an accelerator treatment control system to generate corresponding ion beam flows. The scanning sequence generation module comprises a scanning frequency setting module for dividing scanning point weights of each energy layer of the irradiation target region so that original single scanning becomes m times of scanning; a free motion mode sequence generation module for determining scanning time points of m times of scanning corresponding to each energy layer of the irradiation target region in the free motion mode and generating scanning point sequences in combination with the divided scanning point weights; and a gated mode scanning sequence generation module for determining scanning time points of m times of scanning corresponding to each energy layer of the irradiation target region in the gated mode and generating scanning point sequences in combination with the divided scanning point weights. The free motion mode sequence generation module comprises a motion cycle calculation module for calculating an average motion cycle t1 in the free motion mode; a first adjacent scanning time interval calculation module for dividing the average motion cycle t1 into m parts to obtain a first adjacent scanning time interval t1 / m; a first energy layer repeated scanning module for selecting a time point as a scanning starting time point, obtaining a plurality of scanning time points arranged at equal time intervals according to the first adjacent scanning time interval, and distributing first time scanning to m times of scanning corresponding to a first energy layer of the irradiation target region to the scanning time points; and a first remaining energy layer repeated scanning module for distributing first time scanning to m times of scanning corresponding to other energy layers to corresponding scanning time points by using the same method as that of the first energy layer repeated scanning module to obtain scanning point sequences. The target region design module comprises a target region contour drawing module for reconstructing 3DCT image data of each motion phase based on 4DCT scanning and motion curve data and drawing target region contours of each motion phase; an irradiation mode selection module for determining an irradiation mode according to design requirements and calculating geometric inner target regions and range inner target regions based on the determined irradiation mode and the target region contours of each motion phase; and an irradiation target region determination module for correcting the calculated geometric inner target regions and range inner target regions according to uncertainty factors to form an irradiation target region. The target region contour drawing module comprises an image data reconstruction module for reconstructing 3DCT image data of each motion phase based on acquired 4DCT scanning data; a reference phase target region contour drawing module for screening a motion phase with position repeatability meeting preset requirements as a reference phase from the 3DCT image data and drawing a target region contour of the reference phase; and a remaining phase target region contour drawing module for drawing target region contours of other remaining motion phases except the reference phase. ​ ​ ​ ​ ​ ​ ​ ​ 2. The ion beam rapid scanning irradiation system of claim 1, wherein ​ ​ ​ ​ 3. A system for fast ion beam scanning and irradiation as claimed in claim 2, wherein ​ ​ ​ ​ 4. A system for fast ion beam scanning and irradiation according to claim 3, characterized in that The remaining phase target region contouring module uses a deformation registration method to deform the target region contour of the reference phase to other motion phases when contouring the target region of the remaining motion phases other than the reference phase.

5. The ion beam rapid scanning irradiation system of claim 2, wherein The irradiation mode selection module uses an irradiation mode including a gated treatment mode and a free motion mode according to design requirements; When the free motion mode is used, the geometric inner target region is formed by taking the union of the target region contours of all motion phases; and the range inner target region is formed by taking into account the change in ion beam range caused by the change in tissue density on different motion phases. When the gated treatment mode is used, the geometric inner target region and the range inner target region are calculated by the motion phases within the gating window.

6. The ion beam rapid scanning irradiation system of claim 1, wherein In the scan number setting module, the scan point weight of each energy slice of the irradiation target region is divided in the following ways: Proportional division, in which each scan point weight is divided by the scan number m to obtain the division weight of each scan point; Or fixed single scan amount division, in which the weight of each scan point is divided by the single scan amount to obtain the scan number.

7. The ion beam rapid scanning irradiation system of claim 1, wherein The gated mode scan sequence generation module includes: A gating window calculation module for calculating the size t2 of the gating window in the free motion plus gated mode; A second adjacent scan time interval calculation module for dividing the size of the gating window by m to obtain the second adjacent scan time interval t2 / m; A second initial energy slice repeated scan module for selecting the start point of the gating window as the scan start time, obtaining multiple scan time points arranged at equal time intervals according to the second adjacent scan time interval, and distributing the first to mth scans corresponding to the first energy slice of the irradiation target region to the scan time points; A second remaining energy slice repeated scan module for using the same method as the second initial energy slice repeated scan module to respectively distribute the first to mth scans corresponding to other energy slices to the corresponding scan point sequences.

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