A range safety gate system and method for fixed-beam carbon ion seated position therapy

Abstract

The application relates to the technical field of fixed-beam carbon ion particle therapy body position fixation and range safety gating, and discloses a range safety gating system and method for fixed-beam carbon ion sitting position treatment, which comprises the following: a patient fixing chair which bears a fixed patient and adjusts a beam flow incidence path; a multi-position positioning assembly which realizes individualized sitting position positioning of the patient; a positioning assembly three-dimensional posture recognition module which acquires real-time three-dimensional postures of each positioning assembly; a sitting position reproduction difference acquisition module which acquires a reference posture vector and a split real-time posture vector to generate a body position reproduction difference vector; a fixed-beam coordinate conversion module which judges whether a human body geometric change region corresponding to the positioning assembly and the body position difference invades the beam path; a difference water equivalent thickness calculation module which calculates a difference water equivalent thickness of a split relative simulation positioning when the invasion exists; an adaptive range safety gating module which generates a risk score based on the difference water equivalent thickness and a beam field risk parameter; and operations such as allowing treatment and prohibiting beam emission are executed based on the risk score.

Description

Technical Field

[0001] This application relates to the field of fixed-beam carbon ion particle therapy, specifically to a fixed-beam carbon ion therapy, including but not limited to a fixed-beam carbon ion therapy, and its range safety gating system and method. Background Technology

[0002] Carbon ion radiotherapy is characterized by its limited range, steep dose drop at distal sites, and relatively high biological efficacy, making it suitable for treating some deep tumors, radiation-resistant tumors, and tumors adjacent to vital organs. Compared to photon radiotherapy, carbon ion beams are more sensitive to changes in tissue thickness, material density, and water equivalent thickness along the beam path. Changes in patient position, external positioning device orientation, or the entry of positioning devices into the beam path that alter the water equivalent thickness can cause a deviation in the carbon ion beam range.

[0003] In a fixed-beam carbon ion therapy chamber, the beam direction is relatively fixed. Patient posture is typically adjusted using a patient-fixed chair or treatment platform to achieve different incident angles. Seated therapy can expand the usable beam angle without relying on a large rotating gantry. However, the human torso, pelvis, and limbs have greater freedom of movement in a seated position, making it difficult to stably replicate the posture of the shoulders, torso, pelvis, feet, and upper limbs between treatment sessions, thus increasing the likelihood of postural deviations.

[0004] In seated therapy scenarios, multiple positioning components are required, including head, neck, and shoulder supports, chest and abdomen fixation devices, pelvic positioning grooves, hand grips, forearm supports, and foot pedals. As the therapy chair rotates, rises, and translates, and the patient's position changes, two factors occur: firstly, the patient's own tissues shift geometrically and intrude into the beam path, altering the equivalent thickness of the human tissue water within the beam; secondly, external positioning components may enter the carbon ion beam channel with the patient's posture adjustment. The lack of integrated pre-beam exit verification methods makes it impossible to simultaneously identify seated posture deviations and whether positioning components intrude into the beam path. It is difficult to assess in real time the changes in the equivalent thickness of the beam path water caused by both factors, which can induce carbon ion range drift, leading to insufficient radiation at the distal target area or increasing the risk of irradiation to organs endangered behind the target area. Summary of the Invention

[0005] In view of this, the present application provides a range safety gating system and method for fixed-beam carbon ion seated therapy, which at least solves the problem in the related art that it is difficult to simultaneously identify changes in human body position during seated therapy and disturbances in the equivalent thickness of water in the beam path caused by the intrusion of the positioning component into the beam path, and that it is impossible to dynamically assess the risk of carbon ion range deviation.

[0006] The technical solution of this application embodiment is implemented as follows: In a first aspect, embodiments of this application provide a range safety gating system for fixed-beam carbon ion therapy in a seated posture, the system comprising: The patient fixation chair is used to support and fix the patient, allowing the fixed carbon ion beam to pass through. The patient fixation chair can be rotated, raised, lowered, and translated. It can switch the treatment beam field by changing the spatial orientation of the patient's body relative to the fixed carbon ion beam to form multiple incident angles. The current beam field to be irradiated is selected, and the patient fixation chair is controlled to adjust to the spatial posture corresponding to the current beam field. At the same time, the fixed carbon ion beam is determined to penetrate the multi-site positioning components and the patient's body tissue, and the beam path is determined to be corresponding to the current beam field. The multi-site positioning component is used to perform individualized sitting posture positioning for patients from multiple body parts. The three-dimensional attitude recognition module of the positioning component is used to calculate the real-time three-dimensional attitude of each positioning component in the multi-part positioning component by recognizing the three-dimensional attitude recognition marks deployed on the multi-part positioning component. The sitting posture reproduction differential acquisition module is used to acquire a reference posture vector during the simulation positioning stage and a real-time posture vector during the current treatment stage, based on the real-time three-dimensional posture of each positioning component; the reference posture vector and the real-time posture vector are used to characterize the posture parameter vector formed by the coupling of the multi-site positioning components with the patient's sitting posture; and a posture reproduction differential vector is generated based on the reference posture vector and the real-time posture vector. The fixed beam coordinate transformation module is used to utilize the multi-coordinate system registration relationship and, based on the body position reproduction difference vector, to uniformly transform the multi-site positioning component and the patient's human body geometric position into a fixed beam coordinate system. In the fixed beam coordinate system, it is determined whether the multi-site positioning component and the patient's human body geometric change area corresponding to the body position reproduction difference vector intrude into the beam path corresponding to the current beam field. The differential water equivalent thickness calculation module is used to obtain the total water equivalent thickness of the current beam field reference beam path in the simulation positioning stage and the total water equivalent thickness of the current beam field fractional beam path in the current treatment fractional stage if there is an intrusion into the beam path corresponding to the current beam field; and to calculate the differential water equivalent thickness of the current beam field relative to the simulation positioning stage in the current treatment fractional stage based on the total water equivalent thickness of the current beam field reference beam path and the total water equivalent thickness of the current beam field fractional beam path. The adaptive range safety gating module is used to generate a range gating risk score for the current beam field based on the equivalent thickness of the differential water in the current beam field, the corresponding risk-related parameters of the beam field, and a preset weighting coefficient; and to perform control operations such as allowing treatment, triggering re-acquisition, or prohibiting beam exit based on the comparison result between the range gating risk score and the preset threshold of the current beam field.

[0007] Secondly, embodiments of this application provide a range safety gating method for fixed-beam carbon ion therapy in seated posture, applied to a range safety gating system for fixed-beam carbon ion therapy in seated posture. The system includes: a patient fixation chair, a multi-site positioning component, a three-dimensional posture recognition module for the positioning component, a posture reproduction differential acquisition module, a fixed-beam coordinate transformation module, a differential water equivalent thickness calculation module, and an adaptive range safety gating module; the method includes: The patient fixation chair is used to support and fix the patient, allowing the fixed carbon ion beam to pass through. The patient fixation chair can be rotated, raised, lowered, and translated. It can switch the treatment beam field by changing the spatial orientation of the patient's body relative to the fixed carbon ion beam to form multiple incident angles. The current beam field to be irradiated is selected, and the patient fixation chair is controlled to adjust to the spatial posture corresponding to the current beam field. At the same time, the fixed carbon ion beam is determined to penetrate the multi-site positioning components and the patient's body tissue, and the beam path is determined to be the same as the current beam field. Using the multi-site positioning component, the patient's sitting posture is positioned individually from multiple body parts; Using the three-dimensional attitude recognition module of the positioning component, the real-time three-dimensional attitude of each positioning component in the multi-part positioning component is calculated by recognizing the three-dimensional attitude recognition marks deployed on the multi-part positioning component. Using the sitting posture reproduction differential acquisition module, a reference posture vector is acquired during the simulation positioning stage based on the real-time three-dimensional posture of each positioning component, and a real-time posture vector is acquired during the current treatment stage; the reference posture vector and the real-time posture vector are used to characterize the posture parameter vector formed by the coupling of the multi-site positioning components with the patient's sitting posture; a posture reproduction differential vector is generated based on the reference posture vector and the real-time posture vector. Using the fixed beam coordinate transformation module, based on the multi-coordinate system registration relationship and the body position reproduction difference vector, the multi-site positioning component and the patient's human body geometric position are uniformly transformed into a fixed beam coordinate system. In the fixed beam coordinate system, it is determined whether the multi-site positioning component and the patient's human body geometric change area corresponding to the body position reproduction difference vector intrude into the beam path corresponding to the current beam field. Using the differential water equivalent thickness calculation module, if there is an intrusion into the bundle path corresponding to the current bundle field, the equivalent thickness of the total water in the current bundle field reference bundle path during the simulation positioning stage and the equivalent thickness of the total water in the current bundle field fractional bundle path during the current treatment fractional stage are obtained; based on the equivalent thickness of the total water in the current bundle field reference bundle path and the equivalent thickness of the total water in the current bundle field fractional bundle path, the differential water equivalent thickness of the current bundle field relative to the simulation positioning stage during the current treatment fractional stage is calculated; Using the adaptive range safety gating module, a range gating risk score for the current beamfield is generated based on the equivalent thickness of the differential water in the current beamfield, the corresponding risk-related parameters of the beamfield, and the preset weighting coefficients. Based on the comparison between the range gating risk score of the current beamfield and the preset threshold of the current beamfield, control operations such as allowing treatment, triggering re-acquisition, or prohibiting beam exit are performed.

[0008] The beneficial effects of the technical solutions provided in this application include at least the following: This application embodiment uses a patient fixation chair and multi-site positioning components to fix a seated patient. By collecting a reference posture vector and a real-time posture vector, a position reproduction difference vector is obtained. Under a fixed beam coordinate system, it is determined whether the positioning components or human tissue have intruded into the beam path. When intrusion is found, the equivalent thickness of the differential water in the current beam field is calculated. Based on the equivalent thickness of the differential water in the current beam field and the corresponding beam field risk-related parameters, a risk score is generated and control operations are performed in a graded manner. This improves the ability to identify range disturbance factors in fixed-beam carbon ion seated therapy, reduces the risk of range drift caused by positional deviation and intrusion of the positioning components into the beam path, and reduces the problems of insufficient target dose and excessive irradiation of endangered organs. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a schematic diagram of the composition of a range safety gating system for fixed-beam carbon ion seated therapy provided in an embodiment of this application; Figure 2 A conceptual diagram of a fixed-beam carbon ion therapy chair and a range safety gate control system provided in this application embodiment; Figure 3 This application provides a schematic diagram of the relationship between a three-dimensional attitude recognition marker and a bundle path. Figure 4 This is a flowchart illustrating a range safety gating method for fixed-beam carbon ion therapy in a seated posture, as provided in an embodiment of this application. Detailed Implementation

[0010] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. The following embodiments are used to illustrate this application, but are not intended to limit the scope of this application. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0011] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0012] It should be noted that the terms "first, second, and third" used in the embodiments of this application are merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, and third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0013] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments of this application pertain. It should also be understood that terms such as those defined in general dictionaries should be understood to have a meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0014] This application provides a range safety gating system and method for fixed-beam carbon ion therapy in a seated posture, applied to an electronic device. The electronic device includes, but is not limited to, a treatment control workstation, a medical physics quality control terminal, a treatment control system server, or other types of electronic devices. The functions implemented by this method can be achieved by a processor in the electronic device calling program code. The program code can be stored in a computer storage medium; therefore, the electronic device includes at least a processor and a storage medium. The processor can be used for range safety gating processing of fixed-beam carbon ion therapy in a seated posture, and the storage medium can be used for the data required and generated during the range safety gating process of fixed-beam carbon ion therapy in a seated posture.

[0015] Figure 1 This is a schematic diagram of the composition and structure of a range safety gating system for fixed-beam carbon ion therapy in a seated posture, as provided in an embodiment of this application. Figure 1As shown, the system 100 includes: a patient fixation chair 101, a multi-site positioning component 102, a three-dimensional posture recognition module for the positioning component 103, a sitting posture reproduction differential acquisition module 104, a fixed-beam coordinate transformation module 105, a differential water equivalent thickness calculation module 106, and an adaptive range safety gating module 107; wherein, The patient fixation chair 101 is used to support and fix the patient, allowing the fixed carbon ion beam to pass through. The patient fixation chair can be rotated, raised, lowered, and translated. It can switch the treatment beam field by changing the spatial orientation of the patient's body relative to the fixed carbon ion beam to form multiple incident angles. The current beam field to be irradiated is selected, and the patient fixation chair is controlled to adjust to the spatial posture corresponding to the current beam field. At the same time, the fixed carbon ion beam is determined to penetrate the multi-site positioning components and the patient's body tissue, and the beam path is determined to be corresponding to the current beam field. The fixed-beam carbon ion beam has a fixed beam direction, and the beam source device cannot be rotated, so the incident angle cannot be changed by adjusting the radiation source. The patient fixation chair has multi-degree-of-freedom motion capabilities, enabling the patient to adjust their spatial position and posture as a whole. The incident angle is the direction in which the fixed-beam carbon ion beam enters the patient's human tissue. Different incident angles correspond to different target irradiation areas, i.e., treatment beam fields. The beam path is the propagation path of the fixed-beam carbon ion beam from the emitting end to the target area. The path includes multiple positioning components and various types of patient human tissue, including biological media such as muscles, bones, fat, and organs.

[0016] In the fixed-beam carbon ion therapy scenario, the patient is supported and fixed by a patient-fixed chair, and the carbon ion beam enters the human body along the beam path. Due to the limitations of the fixed-beam equipment structure, the beam source cannot be rotated. Therefore, by adjusting the rotation, height, and translation of the patient-fixed chair, the spatial orientation of the patient relative to the beam is adjusted to obtain multiple incident angles and achieve switching of the treatment beam field. The adjustment of the chair posture will synchronously change the beam path of the carbon ion beam, and the positioning components and human tissue sections through which the beam passes will change accordingly, resulting in changes in the equivalent thickness of the beam path water.

[0017] The multi-site positioning component 102 is used to perform individualized sitting posture positioning of the patient from multiple body parts. In particular, patients are prone to posture deviation during seated therapy. This application relies on multi-site positioning components to coordinate and limit the position from multiple parts of the human body, thereby achieving individualized seated posture fixation and improving the ability to reproduce body position. The human body parts include the head, neck, shoulders, torso, pelvis, feet, and hands.

[0018] The three-dimensional attitude recognition module 103 of the positioning component is used to calculate the real-time three-dimensional attitude of each positioning component in the multi-part positioning component by recognizing the three-dimensional attitude recognition marks deployed on the multi-part positioning component. Among them, the three-dimensional posture recognition mark is a physical feature mark deployed on each positioning component; the mark information is the digital feature data extracted after scanning and recognizing the physical mark; the real-time three-dimensional posture characterizes the current position and deflection angle of a single positioning component in space; when multiple positioning components move or rotate following the patient's sitting posture, the mark information is collected and calculated to obtain the spatial state of each positioning component in real time.

[0019] The sitting posture reproduction differential acquisition module 104 is used to acquire a reference posture vector during the simulation positioning stage and a real-time posture vector during the current treatment stage based on the real-time three-dimensional posture of each positioning component; the reference posture vector and the real-time posture vector are used to characterize the posture parameter vector formed by the coupling of the multi-site positioning components with the patient's sitting posture; and a posture reproduction differential vector is generated based on the reference posture vector and the real-time posture vector. The simulation positioning stage is the pre-treatment planning stage, in which the patient is positioned in a standard treatment posture as a reference standard for subsequent fractionated treatments. The reference posture vector is a multi-dimensional parameter vector constructed by integrating the real-time three-dimensional postures of all positioning components acquired in the simulation positioning stage, representing the standard sitting posture formed by the coupling of multiple positioning components with the patient's sitting posture. The current fractionated treatment stage is the single treatment session in which the patient formally begins irradiation. The real-time posture vector is a multi-dimensional parameter vector constructed by integrating the real-time three-dimensional postures of all positioning components acquired in real-time after the single treatment positioning. The position reproduction difference vector is the difference vector between the real-time posture vector and the reference posture vector, representing the spatial offset of the current positioning relative to the standard posture.

[0020] The fixed beam coordinate transformation module 105 is used to utilize the multi-coordinate system registration relationship and, based on the body position reproduction difference vector, uniformly transform the multi-site positioning component and the patient's human body geometric position into a fixed beam coordinate system. In the fixed beam coordinate system, it is determined whether the multi-site positioning component and the patient's human body geometric change area corresponding to the body position reproduction difference vector intrude into the beam path corresponding to the current beam field. The multi-coordinate system registration relationship is a spatial mapping transformation relationship between pre-established local coordinate systems and the fixed beam coordinate system. The local coordinate systems include the patient CT (Computed Tomography) coordinate system, the patient fixation chair coordinate system, and the local coordinate system of the positioning component. The fixed beam coordinate system is a global coordinate system established based on the fixed carbon ion beam emission path. The patient's body geometric change region represents the range of human body spatial changes caused by the patient's posture shift represented by the position reproduction difference vector. Intrusion into the beam path corresponding to the current beam field refers to the spatial range of the positioning component or the human body change region falling within the effective propagation path of the carbon ion beam corresponding to the current beam field.

[0021] Specifically, the system pre-constructs multi-coordinate system registration relationships, and combines the rotation angle, translation amount, lifting amount of the treatment chair and the actual posture of the positioning components to uniformly transform the positioning components and body position reproduction differential vectors of multiple parts to a fixed beam coordinate system. Then, under the unified coordinate system, it determines whether the area of ​​geometric changes in the human body caused by the positioning components and body position deviation is within the range of the carbon ion beam path.

[0022] The differential water equivalent thickness calculation module 106 is used to obtain the total water equivalent thickness of the current beam field reference beam path in the simulation positioning stage and the total water equivalent thickness of the current beam field fractional beam path in the current treatment fractional stage if there is an intrusion into the beam path corresponding to the current beam field; and to calculate the differential water equivalent thickness of the current beam field relative to the simulation positioning stage in the current treatment fractional stage based on the total water equivalent thickness of the current beam field reference beam path and the total water equivalent thickness of the current beam field fractional beam path. Wherein, the equivalent water thickness of the current beam field reference beam path is the equivalent water thickness value of all media along the path calculated during the simulation positioning phase, obtained from the calculation of the beam path corresponding to the current beam field of the carbon ion beam. This can be expressed as: The medium includes human tissue and multi-component positioning components along the beam path; the equivalent water thickness of the current beam field sub-beam path is the equivalent water thickness calculated along the path medium corresponding to the current treatment sub-beam at the current treatment stage, which can be expressed as: The current beam field differential water equivalent thickness is the difference between the current beam field sub-beam path total water equivalent thickness and the current beam field reference beam path total water equivalent thickness. This difference directly corresponds to the carbon ion beam range offset, which can be expressed by the following formula (1): Formula (1); in, This represents the equivalent thickness of the differential water in the current beam corresponding to the b-th beam. This represents the equivalent thickness of the total water in the current bundle path corresponding to the b-th bundle field, characterizing the equivalent thickness of the water in the bundle path corresponding to the actual posture of the external positioning components and the patient's seated posture reproduction state in the current treatment stage. It represents the equivalent thickness of the total water in the reference bundle path corresponding to the b-th bundle field, and characterizes the equivalent thickness of the water in the bundle path corresponding to the actual posture of the external positioning components and the patient's sitting posture reproduction state during the simulation positioning phase.

[0023] The adaptive range safety gating module 107 is used to generate a range gating risk score based on the current beam field differential water equivalent thickness and the corresponding beam field risk-related parameters and preset weight coefficients; and to perform control operations such as allowing treatment, triggering re-acquisition, or prohibiting beam exit based on the comparison result of the current beam field range gating risk score and the current beam field preset threshold.

[0024] Among them, the corresponding beam field risk-related parameters are the correlation indicators affecting the range safety of carbon ion therapy; the preset weight coefficient is a pre-calibrated weight value used to quantify the degree of influence of each beam field risk-related parameter on range safety; the current beam field range gating risk score is a comprehensive safety assessment score obtained by integrating multiple dimensions of the current beam field risk-related parameters; the adaptive range safety gating module 107 obtains an accurate current beam field range gating risk score through multi-parameter weighted calculation, and judges the treatment safety status based on the current beam field preset threshold, realizing intelligent safety management of the treatment process, effectively avoiding treatment risks caused by body position deviation, beam path abnormality, and range deviation, and ensuring the accuracy and safety of carbon ion beam therapy.

[0025] like Figure 2 As shown, the range risk assessment report of the human-computer interaction module on the right corresponds to the output of the adaptive range safety gating module 107 of the system. The range risk assessment report includes patient position verification, beam path verification, water equivalent thickness (WET) analysis, risk instrument display, and safety judgment results. The adaptive range safety gating module 107 outputs control commands based on the comparison results between the current beam field range gating risk score and the current beam field preset threshold, which correspond to the treatment control status of allowing treatment, triggering re-acquisition, or prohibiting beam exit.

[0026] In the above embodiments, a patient is fixed in a seated position using a patient fixation chair and a multi-site positioning component. A position reproduction differential vector is obtained by collecting a reference posture vector and a real-time posture vector. Under a fixed beam coordinate system, it is determined whether the positioning component or human tissue has intruded into the beam path. When intrusion is found, the equivalent thickness of the differential water in the current beam field is calculated. A risk score is generated based on the equivalent thickness of the differential water in the current beam field and the corresponding beam field risk-related parameters, and control operations are performed in stages. This improves the ability to identify range disturbance factors in fixed-beam carbon ion seated therapy, reduces the risk of range drift caused by positional deviation and intrusion of the positioning component into the beam path, and reduces the problems of insufficient target dose and excessive irradiation of organs at risk.

[0027] In some embodiments, the system further includes: A calibration database is used to pre-store the relative stopping power of each positioning component under different beam fields; The differential water equivalent thickness calculation module is used to obtain the ray travel length of the beam path corresponding to the current beam field in each medium during the simulation positioning stage and the ray travel length of the beam path corresponding to the current beam field in each medium during the current treatment fractionation stage if there is an intrusion into the beam path corresponding to the current beam field. It then combines the relative stopping power of each medium retrieved from the calibration database based on the beam inlet angle corresponding to the current beam field to solve for the total water equivalent thickness of the current beam field reference beam path and the total water equivalent thickness of the current beam field fractionation beam path, respectively. The medium is the positioning component or human tissue.

[0028] The calibration database can record the name, model, unique number, material, thickness, direction-dependent water equivalent thickness corresponding to the incident angle, relative stopping power (RSP), calibration date, validity period, and batch information of each positioning component. For positioning components that may enter the beam path, such as backrests, chest and abdomen fixing shells, head, neck and shoulder fixing components, gripping components, and forearm supports, the calibration database records their WET / RSP parameters under different installation directions and different beam inrush angles. The current beam field differential water equivalent thickness can be calculated using the following formula (2): Formula (2); in, This indicates the ray travel length within medium i of the beam path corresponding to the current beam field (bth beam field) in the current treatment fraction stage; This indicates the ray travel length in each medium of the beam path corresponding to the current beam field (b-th beam field) during the simulation positioning phase; This indicates the relative blocking ability corresponding to the current bundle field (b-th bundle field) in the current treatment phase. This represents the relative stopping power corresponding to the current beam field (the b-th beam field) during the simulated localization phase. This indicates the current equivalent thickness of the total water in the bundled paths. This indicates the equivalent thickness of the total water in the current reference beam path.

[0029] It should be noted that the relative resistance of human tissues can be determined on a case-by-case basis according to the individual patient's condition. It is usually obtained by conversion based on the planned CT images, HU (Hounsfield Unit)-RSP conversion curve, or treatment planning system.

[0030] In the above embodiments, based on a pre-stored calibration database of the relative stopping power of the positioning components under different incident angles, by distinguishing between two types of media, namely the positioning components and human tissue, and combining the accurate calculation benchmark of the beam path length with the equivalent thickness of the total water in the fractional beam path, the calculation accuracy of the differential water equivalent thickness can be improved. This fully considers the range disturbance caused by the external positioning components, making the subsequent range risk assessment results more consistent with the actual treatment conditions.

[0031] In some embodiments, the system further includes a beam field risk feature extraction module and a dynamic threshold generation module; the corresponding beam field risk-related parameters include the current beam field's distal available range safety margin, the current beam field's distal organ-at-risk water equivalent distance, the current beam field uncertainty, the current beam field biological risk coefficient, the current beam field clinical site risk coefficient, the current beam field differential water equivalent thickness trend risk index for the current beam field in historical treatment fractions, the current beam field's sitting posture reproducibility stability score for the current treatment fractions, the current beam field differential water equivalent thickness direction risk marker, a maximum threshold, and a minimum threshold; the current beam field preset threshold includes the current beam field's dynamic allowable threshold and the current beam field's prohibited beam exit threshold, wherein... The beam field risk feature extraction module is used to generate a current beam field risk feature vector based on the current beam field's available range safety margin at the distal end, the current beam field's water equivalent distance to the distal organ at risk, the current beam field uncertainty, the current beam field biological risk coefficient, the current beam field clinical site risk coefficient, the current beam field differential water equivalent thickness trend risk index at the historical treatment fraction stage, the current beam field's sitting posture reproducibility stability score at the current treatment fraction stage, and the current beam field differential water equivalent thickness direction risk marker. The current bundle field preset threshold may not use a uniform fixed empirical value, but is calculated separately for each patient, each treatment session, and each treatment bundle field; the system can first synthesize the current bundle field uncertainty corresponding to the b-th bundle field using the following formula (3). : Formula (3); in, To represent the square root operation, The uncertainty of the three-dimensional attitude recognition of the positioning component can be obtained by repeated scanning or phantom verification from the marker recognition error, attitude inverse calculation error and coordinate transformation error. The WET / RSP calibration uncertainty can be obtained from a water tank, a multilayer ionization chamber, the CT-HU / RSP curve, or actual material measurement data. The uncertainty of image registration and fixed-beam coordinate transformation can be obtained from the CT / CBCT (Cone Beam Computed Tomography) or orthogonal X-ray registration residuals; Uncertainty regarding the reproduction of seated posture or movement during treatment can be estimated from fluctuations in grip pressure, drift of the pelvic pressure center, heel positioning, respiratory movements, or postural drift during treatment. Each factor is projected along the beam direction and converted to an equivalent water thickness, then synthesized using a sum-of-squares and square-root approach.

[0032] For the b-th bundle field, the current bundle field risk feature vector can be generated using the following formula (4). : Formula (4); in, This represents the current safe margin of usable range at the far end of the firing range. This represents the equivalent distance of water to the distal organs at risk from the current bundle field. The current risk factor for wild organisms. The current risk factor for clinical sites in the field of control. The current bundle field differential water equivalent thickness trend risk indicator (past placement deviation trend) is used as the stage of historical treatment. The stability score for the current bundle field sitting posture reproduction during the current treatment fractionation stage; This serves as a risk marker for the equivalent thickness direction of the current bundle field differential water.

[0033] In formula (4), the parameters of the current bundle field risk feature vector are not all fixed values, but are obtained by the treatment plan, image recognition, sensor acquisition, historical fractional recording and clinical rules. It can be obtained from the robustness setting of the treatment plan, the safety margin of the far-end range, and the spatial relationship between the target area and the organ at risk (OAR); The water-equivalent distance from the distal dose drop zone in the planned CT scan to the nearest organ at risk is calculated. The determination can be based on whether the LET / RBE (Linear Energy Transfer / Relative Biological Effectiveness) hotspot is close to the organ at risk, organ sensitivity, and clinical risk level; It can be preset or determined by referring to a table according to the head and neck, chest and abdomen, pelvis and other parts; It can be divided into historical periods. Calculation of the number of offsets in the same direction, slope, or cumulative deviation; The score is obtained by normalized scoring of grip pressure, pelvic pressure center, heel placement, and backrest angle. This indicates the risk in the ΔWET direction, for example, marking a high-risk area when the distal range advances towards an organ at risk.

[0034] The dynamic threshold generation module is used to generate the current bundle field dynamic allowable threshold and the current bundle field prohibited exit threshold based on the maximum threshold, the minimum threshold, the current bundle field distal available range safety margin, the current bundle field uncertainty, the current bundle field biological risk coefficient, the current bundle field differential water equivalent thickness trend risk index in the historical treatment fraction stage, and the current bundle field clinical site risk coefficient. For the b-th bundle field, the dynamic allowable threshold for the current bundle field can be generated using the following formula (5). : Formula (5); in, This indicates that the current dynamic allowable threshold of the bundle field is limited to the minimum threshold. Up to the maximum threshold between, to The weighted parameters are those approved by equipment acceptance testing, physicist configuration, or clinical committee approval; they can also be implemented using threshold strategy tables, rule bases, or validated models. The core principle is that the current bundle field dynamic allowable threshold varies with the patient, fraction, and bundle field, rather than being a fixed empirical threshold. It should be noted that additional factors such as the equivalent distance of the distal organ at risk water in the current bundle field, the current bundle field posture reproducibility stability score at the current treatment fraction stage, and the risk marker in the direction of the current bundle field differential water equivalent thickness can also be introduced to influence the current bundle field dynamic allowable threshold. Make corrections.

[0035] The adaptive range safety gating module is used to generate a range gating risk score for the current beamfield based on the current beamfield differential water equivalent thickness, the current beamfield uncertainty, the current beamfield differential water equivalent thickness directional risk marker, and a preset weighting coefficient; if the current beamfield range gating risk score is less than the current beamfield dynamic allowable threshold, a control operation to allow treatment is executed; if the current beamfield range gating risk score is greater than or equal to the current beamfield dynamic allowable threshold and less than the current beamfield prohibition threshold, a control operation to trigger a re-acquisition for verification is executed; if the current beamfield range gating risk score is greater than or equal to the current beamfield prohibition threshold, a control operation to prohibit beam exit is executed.

[0036] For the b-th beam field, the system calculates the range-gated risk score of the current beam field using the following formula (6). : Formula (6); in, q can be a preset weighting coefficient.

[0037] like < Treatment is permitted and recorded; if ≤ < Then a medical physicist is required to review or provide additional imaging verification; if ≥ If the system determines that the long-range beam may enter the safety zone that endangers organs, then beam delivery is prohibited.

[0038] In the above embodiments, a bundle field risk feature vector is constructed based on multiple bundle field-related risk parameters. A dynamic threshold generation module adaptively generates dynamic allowable thresholds and prohibition thresholds for bundle exit. Risk scores are calculated and graded management is implemented by combining parameters such as differential water equivalent thickness. This approach can break away from the fixed threshold-based judgment method and adaptively adjust the judgment criteria according to different bundle fields and different lesion conditions, thereby enhancing the clinical applicability of the system and improving treatment safety and efficiency.

[0039] In some embodiments, the current beam field preset threshold further includes a current beam field verification threshold, wherein the current beam field verification threshold is greater than the current beam field dynamic allow threshold and less than the current beam field prohibition threshold; The adaptive range safety gating module is used to perform a repositioning or re-acquisition control operation when the current beam field range gating risk score is greater than or equal to the current beam field dynamic allowable threshold and less than the current beam field verification threshold; and to perform a manual verification control operation when the current beam field range gating risk score is greater than or equal to the current beam field verification threshold and less than the current beam field prohibited beam exit threshold.

[0040] Wherein, for the b-th bundle field, the current bundle field verification threshold can be expressed as: Current field verification threshold and the current beam field prohibition threshold Dynamically allowed threshold in the current bundle field Based on the current constraint uncertainty Generate, for example = +λ1· , =min( , +λ2· ), where λ1 and λ2 are preset coefficients, 0 < λ1 < λ2. Alternatively, a threshold strategy table, rule base, or validated model can be used to generate the values. It represents the upper limit of the system's allowed boundary, not a fixed gating threshold; hard stop conditions such as component unlocking, calibration expiration, and low WET window misalignment can directly trigger the prohibition of beam output.

[0041] As shown in Table 1 below, different control operations can be performed based on the comparison results of the current beam field range gating risk score and multiple thresholds.

[0042] Table 1 Range Gating Hierarchical Control Rules

[0043] As shown in Table 1, hard stop conditions may include: the fixation component is not identified or the identification confidence is below the lower limit, the fixation component is in an abnormal locking state, the low WET window is misaligned with the bundle path, the current component batch WET / RSP calibration is expired, the OAR safety distance is below the clinical lower limit, and the same risk source still fails to pass the gating after two treatments.

[0044] After treatment, the system re-collects the orientation and sitting posture reproduction parameters of the positioning components, recalculates the equivalent thickness of the differential water in the current bundle field and the preset threshold, until gating is passed, manual approval is passed, or the treatment is terminated. If multiple consecutive sessions show deviations in the same direction within the same bundle field, the system updates. It will then automatically tighten the preset threshold in subsequent iterations.

[0045] In the above embodiments, an independent verification threshold is added based on the dynamic allowable threshold and the prohibition threshold for beam exit. By setting multiple thresholds to divide the gradient risk range, re-acquisition and repositioning, manual verification, and beam exit prohibition operations are sequentially performed for abnormal situations. This achieves refined risk stratification and treatment, distinguishing between minor deviations that can be automatically corrected and higher-risk deviations that require manual intervention, reducing unnecessary treatment interruptions, and continuously ensuring treatment safety.

[0046] In some embodiments, the system further includes a processing feedback module and an audit trail module, wherein, The treatment feedback module is used to receive various control operations output by the adaptive range safety gating module, push various control operations to the treatment operation table and the machine room display terminal, and record manual review, repositioning or re-collection operation records. The audit trail module is used to record various types of data generated during the simulation positioning phase and each treatment sub-phase, for use in clinical quality control and treatment review.

[0047] In the above embodiments, based on the control operation corresponding to the output of the adaptive range safety gating module, the operation information is pushed to the terminal and the operation behavior is recorded through the treatment feedback module; the treatment data of each stage is completely saved through the audit tracking module; so that staff can intuitively receive treatment instructions, completely retain the data of the whole process, enhance the traceability of the treatment process, and facilitate daily quality control and treatment review.

[0048] In some embodiments, the human limbs include the hand, forearm, head, neck and shoulders, chest and abdomen, pelvis and feet; The multi-part positioning assembly includes a hand gripper, a forearm support, a head, neck and shoulder fixation bracket, a chest and abdomen fixation component, a pelvic positioning groove, a heel groove, and a foot pedal. The hand gripping device is located in front of and below the patient or on both sides of the body to reproduce the posture of the upper limbs, shoulders, chest and trunk; The pelvic positioning groove and the heel groove are used together to limit the posture of the patient's pelvis and feet, and to inhibit the patient's sitting posture from sinking, pelvic tilting and foot position shifting between treatment sessions.

[0049] Among them, the "segmented treatment interval" refers to the period between multiple treatment sessions. By positioning the patient's individualized sitting posture from multiple body parts, stable reproduction of the shoulder, trunk, pelvis, feet, and upper limb postures can be achieved between multiple treatment sessions; for example... Figure 2 As shown, the positioning components configured in the system include a hand gripper consisting of an adjustable grip handle (configured with left and right guide rails), a forearm support with a forearm support pad, and a chest and abdomen fixation component consisting of a chest and abdomen fixation shell and a fixation strap. Figure 2 The horizontal green arrow indicates the incident direction of the fixed-beam carbon ion beam, which propagates along this path and passes through the patient's chest and abdomen. The system also includes a head, neck, and shoulder fixation brace with a thermoplastic mask to restrain the head and neck posture and prevent head and neck movement; a chest and abdomen fixation shell and fixation straps, along with a body vacuum pad, to restrain the patient's trunk and thoracic frame; a pelvic positioning groove to limit pelvic tilt and lateral slippage, addressing the issue of sinking while sitting; and a heel groove and foot pedal to fix the position of the feet and lock the lower limb posture.

[0050] In the above embodiments, based on the concept of multi-limb joint positioning, multiple components such as hand grippers, pelvic positioning grooves, and heel grooves are used to constrain the posture of multiple parts of the human body, suppressing sitting posture sinking, pelvic tilt, and limb displacement; improving the reproduction effect of sitting posture between treatment sessions, reducing the probability of tissue intrusion into the bundle due to human posture drift, and reducing the probability of carbon ion range deviation.

[0051] In some embodiments, both the reference posture vector and the real-time posture vector include the three-dimensional coordinates of the hand gripper, gripping pressure or contact state, forearm support position, pelvic pressure center, heel position, backrest angle, and rotation angle of the patient fixation chair.

[0052] During the simulation positioning phase, the patient forms an individualized sitting posture using hand grippers, forearm supports, pelvic positioning grooves, and heel grooves. The system records parameters such as the three-dimensional coordinates of the grippers, grip pressure or contact state, forearm support position, pelvic pressure center, heel positioning state, backrest angle, and treatment chair rotation angle to construct a baseline posture vector. During the current segmented treatment phase, the above parameters are collected again to construct a real-time posture vector, which is then compared with the above parameters from the simulation positioning phase to obtain a position reproduction difference vector.

[0053] In the above embodiments, the posture vector is jointly constructed based on the geometric information of the positioning component, the pressure state, and the mechanical parameters of the device. The sitting posture state coupled between the positioning component and the human body is characterized by multi-dimensional parameters. This avoids the information loss caused by relying solely on spatial coordinates to describe the body position, improves the accuracy of the body position reproduction differential vector, and more realistically reflects the sitting posture differences between treatment sessions.

[0054] In some embodiments, the patient fixation chair includes a seat, a backrest, a base, a treatment platform connector, and a locking component; the patient fixation chair is connected to the treatment platform via the treatment platform connector, and the treatment platform can rotate, lift, and translate the patient fixation chair to achieve rotation, lifting, and translation adjustments; like Figure 2 As shown, the patient fixation chair itself can adopt a simple sitting posture structure, and the treatment platform or treatment chair (patient fixation chair) can rotate, lift, and translate. The treatment platform / modular base plate with positioning holes serves as the installation reference for the entire treatment chair, providing a unified coordinate system. All posture calculations and coordinate transformations of the positioning components are based on this reference. The treatment platform can be the bottom modular motion base that supports the entire treatment chair, with a built-in six-degree-of-freedom motion mechanism that can drive the treatment chair above to complete translation, lifting, and rotation. The platform has positioning reference holes, beam alignment scales, and a mechanical locking structure to interface with the fixed beam coordinate system (i.e., the fixed beam coordinate system) in the machine room.

[0055] The locking element is used to lock the posture of the patient fixation chair after adjustment is completed; The patient fixation chair is provided with a beam passage area for the carbon ion beam to pass through, and the beam passage area is provided in any of the following ways: The beam passage region retains a solid structure and is made of a low-water equivalent thickness material to reduce beam range disturbance. Among them, low-water-equivalent-thickness materials have extremely low RSP (low-density, low-atomic-number materials, such as thin PE, foamed carbon, and lightweight carbon fiber). Under the same physical thickness, the additional WET increment generated by the beam passing through is very small and hardly changes the carbon ion range. The backrest and base areas of the chair that will be hit by the beam are all processed with low-water-equivalent-thickness materials to avoid the large amount of additional WET deviation caused by conventional metals and thick plastics.

[0056] Alternatively, some solid structures can be removed from the beam flow area to create a low-water equivalent thickness beam window, thereby reducing the range disturbance of the carbon ion beam by utilizing the low-water equivalent characteristics of air.

[0057] In the above embodiments, the patient's position is adjusted based on the multidimensionally adjustable patient fixation chair to achieve irradiation at multiple incident angles; the influence of the patient fixation chair's own structure on the beam is reduced through two beam flow area design schemes; multi-beam field treatment is achieved in a fixed beam treatment environment, reducing the interference of additional water equivalent thickness introduced by the treatment chair body and reducing the systematic error in range calculation.

[0058] In some embodiments, the three-dimensional pose recognition identifier includes at least three non-collinear CT-recognizable low-artifact markers, and each three-dimensional pose recognition identifier is bound to a unique number of the corresponding positioning component; The three-dimensional pose recognition module of the positioning component is used to identify the position of the marker point through the imaging equipment of the simulated positioning stage and each treatment stage, and to calculate the real-time three-dimensional pose of the positioning component in the patient fixed chair coordinate system. The real-time three-dimensional attitude includes at least the model of the corresponding positioning component, installation direction, insertion depth, translation position, rotation angle, position of the low water equivalent thickness beam window, and mechanical locking status.

[0059] like Figure 3 As shown, 7 is a CT-recognizable WET marker plate, 71 is a CT-recognizable marker point, and 72 is the positioning component number / QR code; Beam path A is the case where the carbon ion beam passes through the positioning component. Beam path A passes through the beam injection reference point 10, passes through the positioning component corresponding to the CT-recognizable marker plate, and then enters the patient's body; if the water equivalent thickness deviates, the ion beam range will shift, and the beam will penetrate excessively, irradiating the endangered organ 11 behind the distal end of the target area 12 in the patient's body, bringing a range safety risk; Beam path B is the case where the carbon ion beam avoids the positioning component. Figure 3 The diagram shows that when the beam passes through the positioning assembly, the additional water equivalent thickness is calculated based on the beam's travel length within the positioning assembly and the material's relative stopping power, and the carbon ion beam range risk is determined in conjunction with the target area and the location of the organs at risk.

[0060] In the above embodiments, based on the attitude recognition identifier with a unique number and non-collinear CT marker, the imaging equipment calculates the complete real-time three-dimensional attitude of the positioning component, including information such as installation position, locking status, and beam window position; this improves the integrity and reliability of the attitude recognition of the positioning component, promptly detects abnormalities such as component installation offset and unlocking, and avoids misjudging the beam path condition.

[0061] Figure 4This is a schematic diagram of a range safety gating method for fixed-beam carbon ion therapy in seated posture, provided in an embodiment of this application. The method is applied to a range safety gating system for fixed-beam carbon ion therapy in seated posture. The system includes: a patient fixation chair, a multi-site positioning component, a three-dimensional posture recognition module for the positioning component, a seated posture reproduction differential acquisition module, a fixed-beam coordinate transformation module, a differential water equivalent thickness calculation module, and an adaptive range safety gating module. The method includes: Step S110: Using the patient fixation chair, the patient is supported and fixed, allowing the fixed carbon ion beam to pass through. The patient fixation chair can be rotated, raised, lowered, and translated. It can switch the treatment beam field by changing the spatial orientation of the patient's body relative to the fixed carbon ion beam to form multiple incident angles. The current beam field to be irradiated is selected, and the patient fixation chair is controlled to adjust to the spatial posture corresponding to the current beam field. At the same time, it is determined that the fixed carbon ion beam penetrates the multi-site positioning components and the patient's body tissue, and the beam path is corresponding to the current beam field. Step S120: Using the multi-site positioning component, the patient's individual sitting posture is positioned from multiple body parts. Step S130: Using the three-dimensional attitude recognition module of the positioning component, the real-time three-dimensional attitude of each positioning component in the multi-part positioning component is calculated by recognizing the three-dimensional attitude recognition marks deployed on the multi-part positioning component. Step S140: Using the sitting posture reproduction differential acquisition module, based on the real-time three-dimensional posture of each positioning component, a reference posture vector is acquired during the simulation positioning stage, and a real-time posture vector is acquired during the current treatment segment stage; the reference posture vector and the real-time posture vector are used to characterize the posture parameter vector formed by the coupling of the multi-site positioning components with the patient's sitting posture; based on the reference posture vector and the real-time posture vector, a posture reproduction differential vector is generated. Step S150: Using the fixed beam coordinate transformation module, based on the multi-coordinate system registration relationship and the body position reproduction difference vector, the multi-site positioning component and the patient's body geometric position are uniformly transformed into a fixed beam coordinate system. In the fixed beam coordinate system, it is determined whether the multi-site positioning component and the patient's body geometric change area corresponding to the body position reproduction difference vector intrude into the beam path corresponding to the current beam field. Step S160: Using the differential water equivalent thickness calculation module, if there is an intrusion into the bundle path corresponding to the current bundle field, obtain the total water equivalent thickness of the current bundle field reference bundle path in the simulation positioning stage and the total water equivalent thickness of the current bundle field fractional bundle path in the current treatment fractional stage; based on the total water equivalent thickness of the current bundle field reference bundle path and the total water equivalent thickness of the current bundle field fractional bundle path, calculate the differential water equivalent thickness of the current bundle field in the current treatment fractional stage relative to the simulation positioning stage. Step S170: Using the adaptive range safety gating module, a range gating risk score for the current beam field is generated based on the equivalent thickness of the differential water in the current beam field, the corresponding risk-related parameters of the beam field, and the preset weight coefficient. Based on the comparison between the range gating risk score of the current beam field and the preset threshold of the current beam field, control operations such as allowing treatment, triggering re-acquisition, or prohibiting beam exit are performed.

[0062] This application provides a range safety gating system and method for fixed-beam carbon ion therapy in a seated posture. The system includes a patient fixation chair, a multi-site positioning component, a three-dimensional posture recognition module for the positioning component, a calibration database, a seated posture reproduction differential acquisition module, a fixed-beam coordinate transformation module, a differential water equivalent thickness calculation module, a beam field risk feature extraction module, a dynamic threshold generation module, an adaptive range safety gating module, a treatment feedback module, and an audit trail module.

[0063] During the simulated positioning, the patient sits in a patient-fixed chair. The therapist adjusts the head, neck, shoulders, torso, pelvis, feet, and hand grip positions. The system records the posture of the fixed components and the sitting posture reproduction parameters in the planned state. Before each subsequent treatment fraction, the system collects the current state again, compares it with the simulated positioning or treatment plan state, calculates the differential water equivalent thickness in the fixed beam coordinate system, and generates a dynamic gating threshold based on the current patient, current fraction, and current beam field. The system then outputs the following actions: allow beam exit, manual review, repositioning, prohibit beam exit, or replanning.

[0064] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this application, the sequence numbers of the above-described processes do not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The sequence numbers of the above-described embodiments are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0065] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0066] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be electrical, mechanical, or other forms.

[0067] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units; some or all of the units may be selected to achieve the purpose of the embodiments of this application according to actual needs. In addition, each functional unit in the embodiments of this application may be fully integrated into one processing unit, or each unit may be a separate unit, or two or more units may be integrated into one unit; the integrated unit may be implemented in hardware or in the form of hardware plus software functional units.

[0068] Alternatively, if the integrated units described above are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, or the parts that contribute to related technologies, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause the device automatic test line to execute all or part of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0069] The methods disclosed in the several method embodiments provided in this application can be arbitrarily combined to obtain new method embodiments without conflict. The features disclosed in the several method or device embodiments provided in this application can be arbitrarily combined to obtain new method embodiments or device embodiments without conflict.

[0070] The above description is merely an embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A range safety gating system for fixed-beam carbon ion therapy in a seated posture, characterized in that, The system includes: a patient fixation chair, a multi-site positioning component, a three-dimensional posture recognition module for the positioning component, a sitting posture reproduction differential acquisition module, a fixed beam coordinate transformation module, a differential water equivalent thickness calculation module, and an adaptive range safety gating module. The patient fixation chair is used to support and fix the patient, allowing the fixed carbon ion beam to pass through. The patient fixation chair can be rotated, raised, lowered, and translated. It can switch the treatment beam field by changing the spatial orientation of the patient's body relative to the fixed carbon ion beam to form multiple incident angles. The current beam field to be irradiated is selected, and the patient fixation chair is controlled to adjust to the spatial posture corresponding to the current beam field. At the same time, the fixed carbon ion beam is determined to penetrate the multi-site positioning components and the patient's body tissue, and the beam path corresponding to the current beam field is determined. The multi-site positioning component is used to perform individualized sitting posture positioning for patients from multiple body parts. The three-dimensional attitude recognition module of the positioning component is used to calculate the real-time three-dimensional attitude of each positioning component in the multi-part positioning component by recognizing the three-dimensional attitude recognition marks deployed on the multi-part positioning component. The sitting posture reproduction differential acquisition module is used to acquire a reference posture vector during the simulation positioning stage and a real-time posture vector during the current treatment stage, based on the real-time three-dimensional posture of each positioning component; the reference posture vector and the real-time posture vector are used to characterize the posture parameter vector formed by the coupling of the multi-site positioning components with the patient's sitting posture; and a posture reproduction differential vector is generated based on the reference posture vector and the real-time posture vector. The fixed beam coordinate transformation module is used to utilize the multi-coordinate system registration relationship and, based on the body position reproduction difference vector, to uniformly transform the multi-site positioning component and the patient's human body geometric position into a fixed beam coordinate system. In the fixed beam coordinate system, it is determined whether the multi-site positioning component and the patient's human body geometric change area corresponding to the body position reproduction difference vector intrude into the beam path corresponding to the current beam field. The differential water equivalent thickness calculation module is used to obtain the total water equivalent thickness of the current beam field reference beam path in the simulation positioning stage and the total water equivalent thickness of the current beam field fractional beam path in the current treatment fractional stage if there is an intrusion into the beam path corresponding to the current beam field; and to calculate the differential water equivalent thickness of the current beam field relative to the simulation positioning stage in the current treatment fractional stage based on the total water equivalent thickness of the current beam field reference beam path and the total water equivalent thickness of the current beam field fractional beam path. The adaptive range safety gating module is used to generate a range gating risk score for the current beam field based on the equivalent thickness of the differential water in the current beam field, the corresponding risk-related parameters of the beam field, and a preset weighting coefficient; and to perform control operations such as allowing treatment, triggering re-acquisition, or prohibiting beam exit based on the comparison result between the range gating risk score and the preset threshold of the current beam field.

2. The system according to claim 1, characterized in that, The system also includes: A calibration database is used to pre-store the relative stopping power of each positioning component under different beam fields; The differential water equivalent thickness calculation module is used to obtain the ray travel length of the beam path corresponding to the current beam field in each medium during the simulation positioning stage and the ray travel length of the beam path corresponding to the current beam field in each medium during the current treatment fractionation stage if there is an intrusion into the beam path corresponding to the current beam field. It then combines the relative stopping power of each medium retrieved from the calibration database based on the beam inlet angle corresponding to the current beam field to solve for the total water equivalent thickness of the current beam field reference beam path and the total water equivalent thickness of the current beam field fractionation beam path, respectively. The medium is the positioning component or human tissue.

3. The system according to claim 1, characterized in that, The system also includes a beam field risk feature extraction module and a dynamic threshold generation module; the corresponding beam field risk-related parameters include the current beam field's distal usable range safety margin, the current beam field's distal organ-at-risk water equivalent distance, the current beam field uncertainty, the current beam field biological risk coefficient, the current beam field clinical site risk coefficient, the current beam field differential water equivalent thickness trend risk index for the current beam field in historical treatment fractions, the current beam field's sitting posture reproducibility stability score for the current treatment fractions, the current beam field differential water equivalent thickness direction risk marker, the maximum threshold, and the minimum threshold. The current beam field preset thresholds include the current beam field's dynamic allowable threshold and the current beam field's prohibited exit threshold. The beam field risk feature extraction module is used to generate a current beam field risk feature vector based on the current beam field's available range safety margin at the distal end, the current beam field's water equivalent distance to the distal organ at risk, the current beam field uncertainty, the current beam field biological risk coefficient, the current beam field clinical site risk coefficient, the current beam field differential water equivalent thickness trend risk index at the historical treatment fraction stage, the current beam field's sitting posture reproducibility stability score at the current treatment fraction stage, and the current beam field differential water equivalent thickness direction risk marker. The dynamic threshold generation module is used to generate the current bundle field dynamic allowable threshold and the current bundle field prohibited exit threshold based on the maximum threshold, the minimum threshold, the current bundle field distal available range safety margin, the current bundle field uncertainty, the current bundle field biological risk coefficient, the current bundle field differential water equivalent thickness trend risk index in the historical treatment fraction stage, and the current bundle field clinical site risk coefficient. The adaptive range safety gating module is used to generate a range gating risk score for the current beamfield based on the current beamfield differential water equivalent thickness, the current beamfield uncertainty, the current beamfield differential water equivalent thickness directional risk marker, and a preset weighting coefficient; if the current beamfield range gating risk score is less than the current beamfield dynamic allowable threshold, a control operation to allow treatment is executed; if the current beamfield range gating risk score is greater than or equal to the current beamfield dynamic allowable threshold and less than the current beamfield prohibition threshold, a control operation to trigger a re-acquisition for verification is executed; if the current beamfield range gating risk score is greater than or equal to the current beamfield prohibition threshold, a control operation to prohibit beam exit is executed.

4. The system according to claim 3, characterized in that, The current beam field preset threshold also includes the current beam field verification threshold, which is greater than the current beam field dynamic allow threshold and less than the current beam field prohibition threshold. The adaptive range safety gating module is used to perform a repositioning or re-acquisition control operation when the current beam field range gating risk score is greater than or equal to the current beam field dynamic allowable threshold and less than the current beam field verification threshold. If the current beam field range gating risk score is greater than or equal to the current beam field review threshold and less than the current beam field prohibition threshold, a manual review control operation is performed.

5. The system according to claim 1, characterized in that, The system also includes a handling feedback module and an audit trail module, wherein... The treatment feedback module is used to receive various control operations output by the adaptive range safety gating module, push various control operations to the treatment operation table and the machine room display terminal, and record manual review, repositioning or re-collection operation records. The audit trail module is used to record various types of data generated during the simulation positioning phase and each treatment sub-phase, for use in clinical quality control and treatment review.

6. The system according to claim 1, characterized in that, The human body parts include the hands, forearms, head, neck, shoulders, chest, abdomen, pelvis, and feet; The multi-part positioning assembly includes a hand gripper, a forearm support, a head, neck and shoulder fixation bracket, a chest and abdomen fixation component, a pelvic positioning groove, a heel groove, and a foot pedal. The hand gripping device is located in front of and below the patient or on both sides of the body to reproduce the posture of the upper limbs, shoulders, chest and trunk; The pelvic positioning groove and the heel groove are used together to limit the posture of the patient's pelvis and feet, and to inhibit the patient's sitting posture from sinking, pelvic tilting and foot position shifting between treatment sessions.

7. The system according to claim 6, characterized in that, Both the reference posture vector and the real-time posture vector include the three-dimensional coordinates of the hand gripper, gripping pressure or contact state, forearm support position, pelvic pressure center, heel positioning, backrest angle, and rotation angle of the patient fixation chair.

8. The system according to claim 1, characterized in that, The patient fixation chair includes a seat, backrest, base, treatment platform connector, and locking mechanism; the patient fixation chair is connected to the treatment platform via the treatment platform connector, and the treatment platform can rotate, lift, and translate the patient fixation chair to achieve rotation, lifting, and translation adjustments; The locking element is used to lock the posture of the patient fixation chair after adjustment is completed; The patient fixation chair is provided with a beam passage area for the carbon ion beam to pass through, and the beam passage area is provided in any of the following ways: The beam passage region retains a solid structure and is made of a low-water equivalent thickness material to reduce beam range disturbance. Alternatively, some solid structures can be removed from the beam flow area to create a low-water equivalent thickness beam window, thereby reducing the range disturbance of the carbon ion beam by utilizing the low-water equivalent characteristics of air.

9. The system according to claim 7, characterized in that, The three-dimensional attitude recognition markers include at least three non-collinear CT-recognizable low-artifact markers, and each three-dimensional attitude recognition marker is bound to a unique number of the corresponding positioning component. The three-dimensional pose recognition module of the positioning component is used to identify the position of the marker point through the imaging equipment of the simulated positioning stage and each treatment stage, and to calculate the real-time three-dimensional pose of the positioning component in the patient fixed chair coordinate system. The real-time three-dimensional attitude includes at least the model of the corresponding positioning component, installation direction, insertion depth, translation position, rotation angle, low water equivalent thickness beam window position, and mechanical locking status.

10. A range safety gating method for fixed-beam carbon ion therapy in a seated posture, characterized in that, A range safety gating system for fixed-beam carbon ion therapy in seated posture includes: a patient fixation chair, a multi-site positioning component, a three-dimensional posture recognition module for the positioning component, a seated posture reproduction differential acquisition module, a fixed-beam coordinate transformation module, a differential water equivalent thickness calculation module, and an adaptive range safety gating module; the method includes: The patient fixation chair is used to support and fix the patient, allowing the fixed carbon ion beam to pass through. The patient fixation chair can be rotated, raised, lowered, and translated. It can switch the treatment beam field by changing the spatial orientation of the patient's body relative to the fixed carbon ion beam to form multiple incident angles. The current beam field to be irradiated is selected, and the patient fixation chair is controlled to adjust to the spatial posture corresponding to the current beam field. At the same time, the fixed carbon ion beam is determined to penetrate the multi-site positioning components and the patient's body tissue, and the beam path is determined to be the same as the current beam field. Using the multi-site positioning component, the patient's sitting posture is positioned individually from multiple body parts; Using the three-dimensional attitude recognition module of the positioning component, the real-time three-dimensional attitude of each positioning component in the multi-part positioning component is calculated by recognizing the three-dimensional attitude recognition marks deployed on the multi-part positioning component. Using the sitting posture reproduction differential acquisition module, a reference posture vector is acquired during the simulation positioning stage based on the real-time three-dimensional posture of each positioning component, and a real-time posture vector is acquired during the current treatment stage; the reference posture vector and the real-time posture vector are used to characterize the posture parameter vector formed by the coupling of the multi-site positioning components with the patient's sitting posture; a posture reproduction differential vector is generated based on the reference posture vector and the real-time posture vector. Using the fixed beam coordinate transformation module, based on the multi-coordinate system registration relationship and the body position reproduction difference vector, the multi-site positioning component and the patient's human body geometric position are uniformly transformed into a fixed beam coordinate system. In the fixed beam coordinate system, it is determined whether the multi-site positioning component and the patient's human body geometric change area corresponding to the body position reproduction difference vector intrude into the beam path corresponding to the current beam field. Using the differential water equivalent thickness calculation module, if there is an intrusion into the bundle path corresponding to the current bundle field, the equivalent thickness of the total water in the current bundle field reference bundle path during the simulation positioning stage and the equivalent thickness of the total water in the current bundle field fractional bundle path during the current treatment fractional stage are obtained; based on the equivalent thickness of the total water in the current bundle field reference bundle path and the equivalent thickness of the total water in the current bundle field fractional bundle path, the differential water equivalent thickness of the current bundle field relative to the simulation positioning stage during the current treatment fractional stage is calculated; Using the adaptive range safety gating module, a range gating risk score for the current beamfield is generated based on the equivalent thickness of the differential water in the current beamfield, the corresponding beamfield risk-related parameters, and the preset weighting coefficients. Based on the comparison between the range gating risk score and the preset threshold of the current beamfield, control operations such as allowing treatment, triggering re-acquisition, or prohibiting beam exit are performed.

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