Radioactive source personal dose real-time monitoring device and method based on double-range self-adaptive mechanism

Abstract

The invention provides a radioactive source personal dose real-time monitoring device and a radioactive source personal dose real-time monitoring method based on a double-range self-adaptive mechanism. The radioactive source personal dose real-time monitoring device and method are suitable for intraoperative individual dose collection and dynamic evaluation in the tumor radiotherapy process. The device comprises a flexible attaching substrate, a first measuring range detection sub-module, a second measuring range detection sub-module, a self-adaptive scheduling unit, a temperature compensation module, a breathing synchronous correction module and a wireless communication module. The device can respond to different dose intensities in real time and adaptively switch or fuse channels; the collected dose projection is restored to a planned coordinate system through a breathing phase recognition and target region drift model, and dynamic target region dose tracking is achieved; temperature correction and wireless transmission functions are combined, and intraoperative data visualization and postoperative evaluation are supported. According to the invention, the precision and safety of radiotherapy dose monitoring are improved, and the method is especially suitable for radiotherapy management of areas with significant respiration-induced drift or adjacent key organs.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical radiotherapy, and in particular relates to a device and method for real-time monitoring of individual dose of a radiation source based on a dual-range adaptive mechanism. Background Art

[0002] In modern tumor radiotherapy, ensuring that the radiation dose is accurately and adequately focused on the target lesion while minimizing exposure to surrounding normal tissues and critical organs is a core issue in radiotherapy safety and efficacy assessment. Despite the widespread use of advanced methods such as image-guided radiotherapy (IGRT), four-dimensional CT-assisted planning, and intensity-modulated radiotherapy (IMRT), in actual clinical practice, there are still many technical difficulties that seriously affect treatment accuracy and individualized safety management, including the following: 1. Lack of real-time feedback on dose during surgery, making it impossible for doctors to perceive irradiation deviations At present, most radiotherapy treatments rely on the "theoretical dose distribution" set by the planning system. It is difficult for clinicians to obtain the real-time dose data actually received by the patient's target area during radiotherapy. Once there is a deviation (such as body position error, inaccurate positioning, plan execution error), it may lead to over-irradiation or missed exposure and cannot be corrected in time.

[0003] 2. Respiration-induced target drift results in “planned irradiation ≠ actual irradiation” For chest and abdominal tumors such as lung cancer, liver cancer, and breast cancer, due to the changes in target area position caused by respiratory movement, the patient's actual tumor area drifts from the original planned position during radiotherapy, resulting in part or the entire target area not being accurately irradiated. At the same time, adjacent important organs (such as the heart, spinal cord, and liver portal area) may be "accidentally injured" due to drifting into the high-dose area.

[0004] 3. Traditional dose monitoring methods lack accuracy and lag in response capabilities The thermoluminescent dosimeters (TLDs), MOSFET patches, and surface semiconductor point detectors currently used in clinical practice generally have the following problems: It can only provide cumulative dose and cannot show dynamic changes; The dose response range is narrow, the field is easily saturated at high doses, and the signal-to-noise ratio is low at low doses; It lacks real-time data processing capabilities and wireless feedback interfaces, and cannot meet the requirements of intraoperative closed-loop control. Most monitoring components need to be removed and read after surgery, which causes a time lag.

[0005] 4. Critical organ protection relies heavily on physician experience and lacks quantitative support. When sensitive structures (such as the spinal cord, pulmonary artery, and gastrointestinal tract) require controlled "threshold doses," currently, clinical practice often uses empirical methods such as preoperative "planned blanks" or "setting dose-limiting volumes" to prevent misirradiation. However, due to the lack of a personalized dose monitoring mechanism with real-time tracking, insufficient patient cooperation and slight positioning errors can cause the actual dose coverage area to shift, potentially reducing treatment efficacy at best and causing radiation complications or irreversible damage at worst.

[0006] Current radiotherapy technology has become highly sophisticated, but there are still many unresolved clinical issues in terms of real-time dose visualization, dynamic target alignment, organ protection mechanisms, attachment adaptability, and system linkage capabilities. There is an urgent need to develop a: Can cover different intensity radiation dose ranges; It can realize dynamic tracking, breathing synchronization, and coordinate projection; It can be stably attached to key parts of the human body and support real-time feedback during surgery; A digital dose monitoring device and method that can be linked with existing radiotherapy systems (such as TPS, CBCT, and OIS). Summary of the Invention

[0007] The purpose of the present invention is to provide a real-time monitoring device and method for personal dose of radiation sources based on a dual-range adaptive mechanism. The present invention is proposed to address the above-mentioned key clinical problems and provides an integrated radiotherapy real-time dose monitoring device and method based on dual-range detection + respiratory synchronization + coordinate restoration + temperature compensation + wireless transmission, providing technical support and clinical safety assurance for precise radiotherapy.

[0008] The technical solution adopted in the present invention is as follows: A real-time monitoring device for personal dose of radioactive sources based on a dual-range adaptive mechanism, including: A flexible adhesive base, made of a bendable, highly skin-friendly film material, suitable for attaching to the target area of ​​the chest, abdomen, or neck during or after radiotherapy, and maintaining a non-compressive fit; A plurality of dose detection modules are provided on the flexible attachment substrate, wherein the dose detection modules include: a first range detection submodule, for detecting low-dose radiation signals with high sensitivity; a second range detection submodule, configured to detect high-intensity radiation signals without saturation under high-dose shock conditions; an adaptive scheduling unit, connected to the first range detection submodule and the second range detection submodule, respectively, for analyzing the dose change rate and response trend in real time, and dynamically deciding to enable, switch, or merge the working states of the above submodules; a temperature compensation module, disposed within the flexible adhesive substrate, for collecting temperature data of the skin surface and surrounding areas and performing thermal drift correction on the collected dose signal; a wireless communication module for synchronously transmitting the dosage data and temperature information collected by the device to a terminal display device or a clinical data platform; A data acquisition and storage module, which is used to integrate, record and relay the collected radiation dose, working channel status, temperature data and time stamps; A ray-transmitting window is provided in the middle of the flexible attachment base, and posture recognition and target area alignment marking structures are provided around the flexible attachment base for position calibration with the imaging system of the radiotherapy equipment.

[0009] The first range detection submodule and the second range detection submodule are arranged in a staggered manner on the flexible attachment substrate to form a spatially overlapping detection area, and the data thereof are fused and calculated by the adaptive scheduling unit to output a weighted dose value.

[0010] The temperature compensation module evenly arranges multiple micro-thermistor points on the flexible attachment substrate, and the temperature distribution map measured by the module is used to correct the thermal drift error of the photodetector under low doses.

[0011] The target area alignment marking structure is a three-point reflective optical marking point or an X-ray visible marking point, which is suitable for CT or CBCT imaging system and can be used for automatic position alignment in radiotherapy planning system.

[0012] The device further includes a respiratory synchronization dose marking and correction module for detecting respiratory cycle changes in the patient's chest or abdomen during radiotherapy and achieving respiratory phase synchronization and coordinate correction of dose data, which includes: a flexible strain-piezoelectric belt, mounted in a ring-shaped manner on the periphery of the flexible attachment substrate, for outputting a strain electrical signal related to the respiratory phase in real time; a digital interface chip, used to convert the strain gauge electrical signal into a digital signal and filter out high-frequency noise; a phase segmentation algorithm unit, for calculating the phase segment of the current breath and writing the corresponding mark into the memory; a respiratory synchronization flag register, used to associate a corresponding respiratory phase segment with each set of sampled dose data; A target drift correction model is used to project the collected dose data back to the target planning coordinate system based on the pre-stored "phase-target three-dimensional displacement curve" before surgery, thereby realizing real-time dose correction under dynamic displacement.

[0013] Among them, the "phase-displacement curve" stored in the target drift correction model is generated by the patient's preoperative four-dimensional CT or CBCT image, and a one-to-one coordinate conversion function is established through manual or algorithmic fitting, which is used to map the dose point corresponding to any respiratory phase to the originally planned irradiation target area.

[0014] A method for real-time monitoring of individual dose of a radioactive source comprises the following steps: S1. Before surgery, obtain a three-dimensional planned image of the patient's radiotherapy target area and a phase-target displacement curve, and attach the monitoring device to the skin surface corresponding to the patient's target area; S2, activating the dose detection module and the respiratory synchronization dose marking-correction module to collect radiation dose data and synchronized respiratory phase in real time; S3. In the adaptive scheduling unit, judging whether to switch to the second range detection submodule or enable the fusion mode according to the dose change rate; S4, writing each dose sampling value and the respiratory phase into the respiratory synchronization flag register; S5. Call the target drift correction model to project the coordinates of the corresponding dose points into the planned irradiation target coordinate system, and establish a dose map under respiratory synchronization; S6. Upload the processed data to the doctor's terminal through the wireless communication module to achieve individualized dose assessment and risk warning during / after surgery.

[0015] Compared with the existing technology, the real-time monitoring device for personal dose of radiation source based on dual-range adaptive mechanism of the present invention has carried out systematic technical improvements around the four dimensions of monitoring accuracy, response capability, dynamic adaptability and clinical practicality, which significantly improves the reliability and accuracy of real-time radiotherapy dose monitoring, and has significant beneficial effects of structural optimization, functional enhancement and clear effect verification.

[0016] First, in terms of dose monitoring range and accuracy, existing technologies often use single-range detectors. These detectors either favor low-dose sensitivity but easily saturate at high doses, or have high tolerance but exhibit high noise and unstable readings in low-dose areas, making it difficult to cover dynamic and complex radiotherapy scenarios. This invention innovatively introduces first-range and second-range detection submodules, which are dynamically enabled, switched, or integrated by an adaptive scheduling unit. This allows for highly sensitive, high-resolution monitoring in low-dose phases, while avoiding signal saturation or data interruption during high-dose surges, creating a continuous, stable, and reliable dose tracking path across the entire dose range.

[0017] Secondly, in addressing the problem of target displacement caused by breathing, existing technologies mostly rely on preoperative positioning and breath-holding techniques for rough control, which cannot capture the position drift of the target caused by respiratory movement during surgery. Therefore, there are risks such as irradiation deviation, missed doses, or accidental damage to surrounding organs. The present invention integrates a flexible strain-piezoelectric belt to sense the patient's respiratory rhythm in real time, and combines it with preoperative 4D-CT to establish a "respiratory phase-target displacement curve". This allows each frame of dose data to be accurately mapped back to the spatial position of the current target in the treatment plan coordinate system, thereby dynamically restoring the true dose distribution and effectively solving the problem of disconnection between dynamic target offset and dose feedback.

[0018] In terms of data stability and environmental adaptability, traditional photodetectors or semiconductor probes are susceptible to output drift during use due to factors such as skin temperature fluctuations and radiation thermal effects. This error is particularly likely to be amplified at low doses, affecting the reliability of dose determination. The present invention evenly distributes multiple micro-thermistor points within a flexible adhesive substrate, constructing a two-dimensional temperature distribution map and performing real-time signal correction based on the device's temperature drift characteristics. This system maintains excellent output stability and low-dose detection accuracy even without constant temperature, enhancing the system's robustness in complex clinical environments.

[0019] In addition, traditional monitoring equipment is mostly rigid probes or heavy wearables, which are difficult to attach and have large positioning errors. They are often unable to adapt to intraoperative image registration systems such as CT and CBCT, which seriously restricts their promotion and use in clinical scenarios. The present invention adopts a flexible attachment base structure with excellent fit and skin-friendliness. It can be non-invasively fixed to any position of the patient's chest, abdomen, neck, etc., and combined with a three-point reflective or X-ray visible marker structure, it can achieve automatic registration with mainstream radiotherapy imaging systems. This design not only ensures the stability and accuracy of the patch during treatment, but also seamlessly connects with existing treatment planning systems, image navigation systems, and radiotherapy information systems, making it convenient for doctors to view the triple information of dose-displacement-phase in real time and form a complete and traceable individualized treatment record.

[0020] Overall, this invention organically integrates dual-channel precision control of dose acquisition, synchronous marking of respiratory phases, real-time restoration of dynamic target mapping, and intelligent correction mechanisms for temperature interference, creating a real-time closed-loop radiotherapy dose monitoring platform with high responsiveness, adaptability, and integration capabilities. By synergizing with the hospital's existing 4D-CT, TPS systems, CBCT image registration, and OIS quality control systems, it truly achieves visualization and refined control of individual doses throughout the "planning-execution-feedback" process. This system has significant, verifiable, quantifiable, and traceable clinical benefits in preventing radiotherapy irradiation deviations, protecting adjacent critical organs, assessing efficacy, and warning of risks, significantly outperforming existing single-point, single-pass, static traditional technical approaches. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of a monitoring device of the present invention; Figure 2 Schematic diagram of the modules of the monitoring device of the present invention; Figure 3 Schematic diagram of the respiratory synchronization dose marking and correction module of the present invention; Figure 4 Schematic diagram of the monitoring method of the present invention; Figure 5 Schematic diagram of the flow of the respiratory synchronization dose marking and correction module of the present invention.

[0022] In the figure, 1. Flexible attachment substrate; 11. Radiation transmission window; 12. Target area alignment mark structure; 2. Dose detection module; 21. First range detection submodule; 22. Second range detection submodule; 3. Adaptive scheduling unit; 6. Data acquisition and storage module; 7. Wireless communication module; 9. Respiratory synchronization dose marking and correction module; 91. Flexible strain-piezoelectric belt; 92. Digital interface chip; 93. Phase segmentation algorithm unit; 94. Respiratory synchronization mark register; 95. Target area drift correction model. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] See also Figure 1 and 2 , a real-time monitoring device for personal dose of radioactive sources based on a dual-range adaptive mechanism, including: A flexible attachment base 1 is made of a flexible, highly skin-friendly film material and is suitable for attachment to the surface of the target area of ​​the chest, abdomen, or neck during or after radiotherapy, maintaining a non-compressive fit. Specifically, the flexible attachment base 1 used in the present invention is a piece of integrally formed medical-grade elastic film, preferably made of thermoplastic polyurethane (TPU) or medical silicone sheet, which has good skin-friendliness, breathability, and conformability. Its thickness is controlled between 0.2mm and 0.5mm, which is sufficient to support the sensor components without causing a sense of oppression. The overall shape of the base is optimized according to the contour of the human torso and can be oval, round, or horseshoe-shaped. This base structure allows attachment to different surfaces such as the chest, abdomen, or neck target area. The attachment method is to preset a disposable medical pressure-sensitive rubber ring on the edge of the patch to achieve rapid positioning and prevent displacement.

[0025] A plurality of dose detection modules 2 are provided on the flexible attachment substrate 1, and the dose detection modules 2 include: a first range detection submodule 21, for detecting low-dose radiation signals with high sensitivity; a second range detection submodule 22, for detecting high-intensity radiation signals without saturation under high-dose shock; The first range detection submodule 21 and the second range detection submodule 22 are arranged in a staggered manner on the flexible attachment substrate 1 to form a spatially overlapping detection area, and the data thereof are fused and calculated by the adaptive scheduling unit 3 to output a weighted dose value.

[0026] Specifically, the first range detection submodule 21 is a high-sensitivity detector that uses a PIN photodiode array and is equipped with a low-noise amplifier circuit, suitable for detecting weak radiation signals as low as 0.001 Gy / min; The second range detection submodule 22 is a wide dynamic range detector that uses a resistive probe or a small ion chamber structure. It is suitable for operation in high-dose impact scenarios above 1 Gy / min to ensure non-saturation.

[0027] The two submodules are embedded in a staggered arrangement beneath the flexible adhesive substrate 1. Each unit area houses both the first-range detection submodule 21 and the second-range detection submodule 22, creating a spatially overlapping detection zone. This design enables high-precision sampling at low doses while avoiding saturation or misreading in sudden high-dose conditions, resulting in complete dose coverage.

[0028] An adaptive scheduling unit 3 is connected to the first range detection submodule 21 and the second range detection submodule 22, respectively, to analyze the dose change rate and response trend in real time and dynamically decide whether to enable, switch, or integrate the operating states of the above submodules. The adaptive scheduling unit 3 is the core processing and control module of the present invention, integrating a main control MCU, an analog-to-digital converter (ADC), a data buffer, and a decision logic module. Its working mechanism is as follows: 1. The system defaults to operating in the first range detection submodule 21; 2. The MCU reads the output voltage regularly and calculates the dose change rate per unit time in real time; 3. When the dose rate rises above a preset threshold (e.g., 0.2 Gy / min / s), or the output level approaches a saturation value, the adaptive scheduling unit 3 automatically shuts down the first range detection submodule 21 and simultaneously activates the second range detection submodule 22. 4. During periods of high dynamic change, the system can also simultaneously activate the first range detection submodule 21 and the second range detection submodule 22, and combine their signal outputs by setting weighting factors (e.g., W1\:W2 = 0.7:0.3) to achieve smooth switching between ranges. 5. Switch the logical record and mark the "working channel status" of the current data frame for subsequent analysis or risk tracking.

[0029] A temperature compensation module, located within the flexible adhesive substrate 1, collects temperature data from the skin surface and surrounding areas and performs thermal drift correction on the collected dose signal. The temperature compensation module evenly distributes multiple micro-thermistor points on the flexible adhesive substrate 1. The measured temperature distribution map is used to correct the thermal drift error of the photodetector under low-dose conditions. The micro-thermistor points are NTC thermistor points, with 6 to 12 points. The data is centrally collected by the adaptive scheduling unit 3 to construct a two-dimensional temperature distribution map.

[0030] This image can be used for the following correction steps: 1. For each dose detection module, its adjacent thermal point provides the current temperature value; 2. The MCU automatically adjusts the output of the first range detection submodule 21 based on the device's temperature-response drift calibration curve; 3. The correction formula uses first-order or second-order polynomial fitting to ensure that the output error in the low-dose range is controlled within ±5%.

[0031] a wireless communication module 7, used to synchronously transmit the dose data and temperature information collected by the device to a terminal display device or a clinical data platform; A data acquisition and storage module 6 is used to integrate, record and relay the collected radiation dose, working channel status, temperature data and timestamp. The format is: [timestamp] + [channel dose of the first range detection submodule 21] + [channel dose of the second range detection submodule 22] + [temperature dot matrix] + [respiratory phase] + [corrected coordinates]; the data is stored in the FLASH cache area and uploaded to the display terminal at the clinician end; the radiotherapy control center server; or the remote cloud storage platform via BLE5.0 or WiFi through the wireless communication module 7 at regular intervals to achieve remote follow-up and dose analysis after surgery.

[0032] A radiation-transmitting window 11 is provided in the center of the flexible adhesive substrate 1, and a posture recognition and target alignment marking structure 12 is arranged around it for position calibration with the radiotherapy equipment imaging system. The target alignment marking structure 12 is a three-point reflective optical marking point or X-ray visible marking point, which is suitable for CT or CBCT imaging systems and can be used for automatic position alignment in the radiotherapy planning system. Its forms include: X-ray visible metal microspheres (tungsten or platinum, 1 mm in diameter); Reflective ball cover structure, suitable for optical camera alignment; The three points form a non-collinear equilateral or isosceles triangle layout.

[0033] After using the CBCT or EPID imaging system to acquire images during surgery, the algorithm can automatically identify the three-point positions and achieve automatic alignment with the coordinate system of the target area planning image, greatly improving the accuracy of radiotherapy targeting and avoiding dose deviation caused by attachment errors.

[0034] The radiation transmission window 11 is a rectangular, circular or elliptical radiation transmission window 11, which is made of a polyimide film with a thickness of less than 50 μm and a radiation transmittance of more than 90%, ensuring that the radiotherapy rays can effectively penetrate and be accurately received by the detection module below.

[0035] For further information, see Figure 3 and Figure 5 The device further includes a respiratory synchronization dose marking and correction module 9, which is used to detect the respiratory cycle changes of the patient's chest or abdomen during radiotherapy and realize the respiratory phase synchronization and coordinate correction of the dose data, which includes: A flexible strain-piezoelectric belt 91 is installed in a ring-shaped manner on the periphery of the flexible attachment substrate 1, and is used to output a strain electrical signal related to the respiratory phase in real time; A digital interface chip 92, used to convert the strain electrical signal into a digital signal and filter out high-frequency noise; a phase segmentation algorithm unit 93 for calculating the phase segment of the current breath and writing the corresponding mark into storage; a respiratory synchronization flag register 94 for associating a corresponding respiratory phase segment with each set of sampled dose data; Because the chest and abdomen target areas move significantly with respiration, traditional patch dose monitoring suffers from registration drift errors. To address this, the device features a dedicated respiratory synchronized dose marking and correction module 9, the core components of which are as follows: 1) Flexible strain-piezoelectric belt 91: Made of PVDF piezoelectric film or conductive fiber, it has high strain sensitivity. It is arranged in a ring around the periphery of the patch and distributed along the stress-bearing areas of the chest and abdomen. It collects skin stretch changes caused by respiratory movement in real time and outputs a strain voltage waveform.

[0036] 2) Digital interface chip 92: Equipped with high-pass and low-pass filters, analog-to-digital conversion, and buffer circuits; the output waveform frame rate is 10 Hz, and the maximum noise suppression is >40 dB.

[0037] 3) Phase segmentation algorithm unit 93: uses FFT to extract the main frequency of the waveform; identifies the current respiratory phase (such as the pre-inspiratory peak, mid-expiratory phase, etc.) through the zero crossing method or amplitude segmentation method; outputs a phase label, which is synchronously updated once per second.

[0038] 4) Respiratory synchronization flag register 94: binds the sampling dose of each frame to the current phase segment and writes it; data can be subsequently traced back by phase to construct a dose-phase heat map.

[0039] 5) Target drift correction model 95: Based on the patient's preoperative 4D-CT or CBCT images; extracts the three-dimensional displacement value of the target area at each respiratory phase; establishes a "phase to coordinate transformation function" through spline function or neural network fitting; and projects the coordinates back to the target area planning system at each dose sampling to achieve real-time dose reconstruction.

[0040] See also Figure 4 A method for real-time monitoring of individual dose of a radioactive source comprises the following steps: S1. Before surgery, obtain the patient's radiotherapy target area 3D planning image and phase-target displacement curve, and attach the monitoring device to the patient's skin surface corresponding to the target area; S2, activate the dose detection module 2 and the respiratory synchronization dose marking and correction module 9 to collect radiation dose data and synchronized respiratory phase in real time; S3, in the adaptive scheduling unit 3, judging whether it is necessary to switch to the second range detection submodule 22 or enable the fusion mode according to the dose change rate; S4, writing each dose sampling value and the respiratory phase into the respiratory synchronization flag register 94; S5. Calling the target drift correction model 95 to project the coordinates of the corresponding dose points into the planned irradiation target coordinate system, and establishing a dose map under respiratory synchronization; S6. Upload the processed data to the doctor's terminal through the wireless communication module 7 to achieve individualized dose assessment and risk warning during / after surgery.

[0041] More specifically, the clinical method for real-time monitoring of individual radiation doses includes the following steps: Step S1: Preoperative planning and device attachment ① Use four-dimensional CT (4D-CT) or CBCT to obtain three-dimensional imaging data of the patient's target area and respiratory cycle information; ② Extract the three-dimensional displacement data of the target area under each respiratory phase segment and establish a "respiratory phase-displacement curve"; ③ Clean the patient's skin surface and select a flexible adhesive substrate 1 that matches the target area; ④ Attach the real-time monitoring device of the present invention to the body surface area corresponding to the target area (such as the chest of a breast cancer patient or the abdomen of a liver cancer patient); ⑤ Adjust the device to align with the center of the irradiation so that the ray transmission window 11 is located at the projection of the target center; ⑥ Complete three-point position alignment in the CT or CBCT imaging system through the marker point 12 to ensure that the device coordinates are consistent with the treatment plan coordinates.

[0042] Step S2: Activate each functional module and initialize the state ① Turn on the power of the monitoring device and activate the dose detection module 2; ② Simultaneously start the respiratory synchronized dose marking and correction module 9, including the flexible strain-piezoelectric belt 91 and the digital interface chip 92; ③ The adaptive scheduling unit 3 starts initialization testing of the first / second range submodule and reads the baseline signal; ④The temperature compensation module reads the value of each thermistor point and generates an initial temperature distribution map; ⑤The data acquisition module records the timestamp synchronously and starts the cyclic sampling preparation.

[0043] Step S3: Real-time dose acquisition and range switching during intraoperative radiotherapy ① After the radiation source is turned on, the dose detection module receives the radiation signal in real time; ② By default, the first range detection submodule 21 is used for low-dose and high-sensitivity acquisition; ③ If it is detected that the dose rate change exceeds the set threshold (e.g., >0.3 Gy / min / s), or the signal approaches saturation, the adaptive scheduling unit 3 automatically switches to the second range detection submodule 22 or enables fusion acquisition; ④ The dose data, working channel status, respiratory phase label and timestamp collected at the same time are stored in the buffer area.

[0044] Step S4: Real-time analysis and synchronous marking of respiratory phase ① The respiratory synchronization module captures the chest or abdominal wall movement through the flexible strain-piezoelectric belt 91 and extracts the respiratory waveform; ② Calculate the current respiratory phase using the phase segmentation algorithm unit 93 and identify it as "peak inhalation", "mid-inhalation" or "early expiratory phase"; ③Write the current respiratory phase segment number into the respiratory synchronization flag register 94; ④ Bind the phase segment number to the corresponding dose data to synchronize each frame of dose data with the respiratory state.

[0045] Step S5: Target drift correction and coordinate mapping ① Call the pre-set "respiratory phase-three-dimensional displacement curve" and extract the target displacement vector at the current phase using the target drift correction model 95; ② Map the collected dose point positions and restore them to the treatment plan coordinate system; ③ Under dynamic respiratory displacement conditions, three-dimensional coordinate correction is performed on all dose points to construct real-time dose heat maps and cumulative dose maps; ④ Matching dose data with displacement coordinates in real time to prevent clinical errors such as “dose miss” or “insufficient irradiation” caused by body surface position shift; ⑤ Generate a corrected “dose-position map under respiratory synchronization” for subsequent clinical evaluation or automatic control interface linkage.

[0046] Step S6: Real-time data integration and wireless upload ① The data acquisition and storage module 6 packages the complete information of the current frame, including: dose data (first / second submodule), working channel status (main channel, fusion, switching mark), respiratory phase label, temperature value distribution, corrected coordinates and timestamp; ② All data is cached in the built-in Flash storage chip in a structured frame format; ③ Every 5 seconds or after the set sampling period, it is sent to the doctor's terminal or the hospital clinical data platform through the wireless communication module 7; ④The data platform can display the actual received dose of the current target area, the cumulative dose change trend, the respiratory induced offset and the risk warning information in real time.

[0047] Step S7: Postoperative individual dose analysis and closed-loop management ① After radiotherapy, the doctor's terminal can call up the patient's complete dose monitoring record to review the radiotherapy period: dose curve, respiratory phase variation, dose window or overlap, and temperature abnormality alarm; ②Comparing the dose distribution of the original plan, the system automatically evaluates the actual target dose achievement rate. If there are areas with insufficient dose, the doctor can decide to retake the image or adjust the plan; ③ Data is synchronized to the patient medical record system and radiotherapy quality control database to provide support for subsequent treatment optimization; ④ If the device enables a respiratory training auxiliary interface (such as external monitoring and synchronous feedback), it can also be used for preoperative training or intraoperative interactive control to improve patient cooperation.

[0048] Furthermore, in clinical radiotherapy, especially for patients undergoing abdominal or pelvic radiotherapy (e.g., for liver cancer, pancreatic cancer, and uterine cancer), preoperative differences in the state of the intestinal, gastric, or bladder contents can cause inconsistencies in the radiation attenuation path, leading to dose deviations. During actual treatment, doctors often struggle to determine in real time whether patients have eaten, drunk, or defecated. Traditional dose detection devices are completely unable to identify or compensate for this, resulting in a significant source of clinical dose uncertainty.

[0049] In this embodiment, in order to solve the problem of inconsistent ray attenuation paths caused by changes in the state of the patient's internal abdominal cavity contents during radiotherapy, thereby leading to dose monitoring distortion, the present invention proposes an "internal medium dynamic compensation mechanism" to improve the spatial reliability and temporal stability of dose values ​​in abdominal and pelvic target area radiotherapy.

[0050] The core concept of this mechanism is to indirectly infer the changing state of the body cavity contents through detailed analysis of abdominal surface deformation patterns during breathing, thereby modifying the credibility weight of real-time radiation dose data. This method does not rely on additional hardware or direct imaging analysis, but instead fully utilizes the data output by the flexible strain-piezoelectric breathing belt already in the original solution of this invention, combined with an intelligent algorithm module for inference and analysis.

[0051] In practice, the belt is attached to the periphery of the abdomen during radiotherapy, recording in real time the expansion and contraction of the abdominal wall caused by respiratory movement. The system automatically extracts the waveform of a complete respiratory cycle every few seconds and analyzes multiple morphological characteristics, such as changes in respiratory amplitude, the temporal distribution of inhalation and exhalation, waveform symmetry, and the stability of the rhythm between consecutive waveforms.

[0052] By comparing these respiratory waveform features with the "fasting reference waveform model" established preoperatively, the system can determine whether the patient is currently in a normal emptying state, a state of increased content, or a fasting state. For example, if the abdominal wall expands less during inspiration, the top of the waveform flattens, the cycle lengthens, and the difference between the previous and next cycles increases, the system can infer that the patient has a large amount of abdominal content, which may affect the consistency of the radiation propagation path.

[0053] Based on this inference, the system assigns a confidence weighting factor to the radiation dose data collected for the current frame, corresponding to the state. If the frame is judged to be "overfilled," the dose value for that frame is adjusted downward or marked as "possibly interfered with" on the physician's terminal. If the frame is judged to be "empty," no correction is made, retaining the original data output.

[0054] This correction mechanism is fully compatible with the "Respiratory Synchronization Marker" and "Coordinate Restoration Correction" modules in the original solution, without changing the original data structure or affecting the respiratory phase marking function. Instead, by increasing the ability to perceive internal physiological changes, the projection results of each dose point on the 3D atlas are more realistic and clinically meaningful.

[0055] Ultimately, when doctors review dose data maps during or after surgery, they can simultaneously see triple labels of "dose value," "spatial position," and "current content status," and use this to determine whether the dose data can be used for evaluation, whether it requires repositioning, or to warn of potential irradiation deviations.

[0056] This mechanism is particularly suitable for precise radiotherapy scenarios of abdominal and pelvic targets such as liver cancer, pancreatic cancer, and uterine cancer. It fills the technical gap where traditional patch dose monitoring is completely unable to perceive the "internal state", and provides an ingenious, non-invasive compensation path that can be implemented based on existing structures.

[0057] The following are several typical clinical application cases based on the "Real-time Personal Dose Monitoring Device for Radioactive Sources with a Dual-Range Adaptive Mechanism" of this invention. These cases cover representative tumor radiotherapy scenarios in high-risk, highly dynamic and variable areas such as the chest, abdomen, and neck. They demonstrate the practical application value, technical advantages, and key role of this solution in precision therapy: Case 1: Patient with left-sided breast cancer (close to the heart) receiving adjuvant radiotherapy after surgery Patient characteristics: A 47-year-old woman underwent breast-conserving surgery and left breast tumor resection.

[0058] Treatment challenges: The left breast target area is adjacent to the heart, and there is a high risk of overlap between the heart and the target area during deep inspiration. Traditional radiotherapy may accidentally irradiate the myocardium.

[0059] Device usage: Attach the device to the skin above the left chest; monitor the target dose in real time and record the respiratory phase; use the calibration model in the "deep inspiration and breath-hold" state to restore the dose coordinates to the target position under deep inspiration.

[0060] Application results: Verified by the hospital's DICOM-RS data connection and comparison of real-time monitoring data with the treatment plan, the MHD was reduced by approximately 0.8 Gy; PTV coverage remained at > 96.5%, confirming that the target area was not missed due to breath-hold displacement; Case 2: Patient receiving radiotherapy for liver cancer in the diaphragmatic region (large movement up and down with breathing) Patient characteristics: A 62-year-old male with a tumor in the right lobe of the liver, located in the dome of the liver, and mild emphysema.

[0061] Treatment challenges: The tumor moves up and down by up to 1.8 cm with breathing, and conventional radiotherapy has the risk of off-target effects.

[0062] Device usage: Attached to the skin of the right upper abdomen; the respiratory belt monitors the respiratory phase in real time; each frame dose is matched with the "phase-shift model" and the three-dimensional coordinates are automatically restored.

[0063] Application effect: Verification by CBCT image registration and dose fusion software showed that the D95 difference in the target area was reduced from ±7.4% to ±1.9%; the Dice index in the overlapping area was improved to 0.92 (better than 0.77 without correction); Case 3: Patient with parahilar small cell lung cancer (target area adjacent to major blood vessels) Patient characteristics: 55-year-old male, small cell lung cancer, target area near the pulmonary artery; Treatment challenges: The pulmonary artery and aortic arch are extremely susceptible to accidental radiation damage; Device Usage: The device is attached to the right side of the midline of the chest; dynamic dose acquisition and dose slope change detection are used to identify sudden dose peaks; high-speed switching to the second range submodule ensures stable operation and avoids saturation; temperature compensation mechanism corrects thermal drift.

[0064] Application effect: Automatically identify high-dose impact segments and maintain data continuity; compare the hospital's TPS plan with the actual curve, discover a 10s high-dose segment error, and correct the plan; consistent with the data exported by the record-and-verification system (R&V), with clinical audit traceability.

[0065] Case 4: Patient with laryngeal cancer undergoing radiotherapy of the stump target area after surgery (complex structure and narrow area) Patient characteristics: A 60-year-old male underwent partial laryngectomy followed by radiotherapy; Treatment challenges: The target area is located in the central neck, which has dense structures, thin skin, and strong interference with breathing / swallowing; Device Usage: The device is miniaturized and attached below the Adam's apple. It uses a respiratory phase + micro-motion interference discrimination algorithm to identify displacement caused by swallowing. Error frames are automatically eliminated to generate a continuous effective dose map.

[0066] Application effect: After the monitoring device was activated, 15 dose jump frames caused by swallowing were effectively eliminated; the final frame efficiency was 98.6%, which was used for later dose reconstruction; after the output data of this device was loaded into the hospital's Pinnacle / Eclipse system, the heat map matching degree was >94%.

[0067] Case 5: Re-irradiation of a patient with a recurrent tumor near the mediastinum (high risk of cumulative dose exceeding the standard) Patient characteristics: A 69-year-old woman who had received thoracic radiotherapy was diagnosed with a focal recurrence in the perimediastinum.

[0068] Treatment challenges: The dose to the original irradiated area is close to critical, and the allowable dose to OARs (such as the spinal cord) has decreased; radiotherapy planning requires accurate calculation of the "remaining available dose"; Device Usage: A real-time monitoring device is attached during the re-irradiation process; all actual doses are mapped and superimposed with historical data; the system can calculate cumulative dose cloud maps and provide organ threshold alarms; Application effect: The actual intraoperative collected dose was spatially overlapped with the historical planned dose; the actual cumulative dose to the spinal cord was judged to have not exceeded the critical threshold of 45 Gy; and quantitative verification was achieved by comparing the DVH curves output by the hospital's radiotherapy quality management system (OIS).

[0069] In summary, the present invention has demonstrated stable and verifiable clinical beneficial effects in multiple typical high-risk radiotherapy scenarios, and has achieved a transition from the "data monitoring" level to the "dynamic guidance + real-time safety control" level, with obvious clinical promotion value and technological substitution potential.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A real-time monitoring device for personal dose of radioactive source based on a dual-range adaptive mechanism, characterized in that: include: A flexible attachment base (1) is made of a bendable, highly skin-friendly film material, suitable for attachment to the surface of the target area of ​​the chest, abdomen or neck of a radiotherapy patient during or after surgery, and maintains a non-compressive fit; A plurality of dose detection modules (2) are provided on the flexible attachment substrate (1), wherein the dose detection modules (2) include: a first range detection submodule (21) for detecting low-dose radiation signals with high sensitivity; a second range detection submodule (22) for detecting high-intensity radiation signals in an unsaturated manner under high-dose shock; an adaptive scheduling unit (3), connected to the first range detection submodule (21) and the second range detection submodule (22), respectively, for real-time analysis of the dose change rate and response trend, and dynamically determining whether to enable, switch, or merge the working states of the above submodules; a temperature compensation module, arranged in the flexible attachment base (1), for collecting temperature data of the skin surface and the surrounding area, and performing thermal drift correction on the collected dose signal; a wireless communication module (7) for synchronously transmitting the dosage data and temperature information collected by the device to a terminal display device or a clinical data platform; a data acquisition and storage module (6) for uniformly integrating, recording and relaying the collected radiation dose, working channel status, temperature data and time stamp; A ray transmission window (11) is provided in the middle of the flexible attachment base (1), and a posture recognition and target area alignment marking structure (12) is provided around the flexible attachment base (1) for position calibration with an imaging system of a radiotherapy device.

2. The monitoring device according to claim 1, characterized in that: The first range detection submodule (21) and the second range detection submodule (22) are arranged in a staggered manner on the flexible attachment substrate (1) to form a spatially overlapping detection area, the data of which are fused and calculated by the adaptive scheduling unit (3) to output a weighted dose value.

3. The monitoring device according to claim 1, wherein: The temperature compensation module evenly arranges a plurality of micro-thermistor points on a flexible attachment substrate (1), and the temperature distribution diagram measured by the module is used to correct the thermal drift error of the photodetector under low dose conditions.

4. The monitoring device according to claim 1, wherein: The target area alignment marking structure (12) is a three-point reflective optical marking point or an X-ray visible marking point, which is suitable for a CT or CBCT imaging system and can be used for automatic position alignment in a radiotherapy planning system.

5. The monitoring device according to claim 1, characterized in that: The device further comprises a respiratory synchronization dose marking and correction module (9) for detecting respiratory cycle changes of the patient's chest or abdomen during radiotherapy and achieving respiratory phase synchronization and coordinate correction of dose data, which comprises: A flexible strain-piezoelectric belt (91) is installed in a ring-shaped manner on the periphery of the flexible attachment base (1) and is used to output a strain electrical signal related to the respiratory phase in real time; a digital interface chip (92) for converting the strain electrical signal into a digital signal and filtering out high-frequency noise; a phase segmentation algorithm unit (93), used for calculating the phase segment of the current breath and writing the corresponding mark into the memory; a respiratory synchronization flag register (94) for associating a corresponding respiratory phase segment with each set of sampled dose data; A target drift correction model (95) is used to project the collected dose data back to the target planning coordinate system based on the "phase-target three-dimensional displacement curve" stored before the operation, so as to realize real-time dose correction under dynamic displacement.

6. The monitoring device according to claim 1, characterized in that: The "phase-displacement curve" stored in the target drift correction model (95) is generated from the patient's preoperative four-dimensional CT or CBCT image, and a one-to-one coordinate conversion function is established through manual or algorithmic fitting to map the dose point corresponding to any respiratory phase to the originally planned irradiation target area.

7. A method for real-time monitoring of individual radiation doses based on the monitoring device of claim 6, characterized in that: The following steps are involved: S1. Before surgery, obtain a three-dimensional planned image of the patient's radiotherapy target area and a phase-target displacement curve, and attach the monitoring device to the skin surface corresponding to the patient's target area; S2, activating the dose detection module (2) and the respiratory synchronization dose marking and correction module (9) to collect radiation dose data and synchronized respiratory phase in real time; S3, in the adaptive scheduling unit (3), judging whether it is necessary to switch to the second range detection submodule (22) or enable the fusion mode according to the dose change rate; S4, writing each dose sampling value and the respiratory phase into the respiratory synchronization mark register (94); S5, calling the target drift correction model (95) to project the corresponding dose point coordinates into the planned irradiation target coordinate system, and establishing a dose map under respiratory synchronization; S6. The processed data is uploaded to the doctor's terminal via the wireless communication module (7) to achieve individualized dose assessment and risk warning during and after surgery.

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