Device and Method for Real-Time Personal Dose Monitoring of Radiation Sources Based on Dual-Range Adaptive Mechanism

Abstract

This invention provides a device and method for real-time monitoring of individual radiation source dose based on a dual-range adaptive mechanism, suitable for intraoperative individual dose acquisition and dynamic assessment during tumor radiotherapy. The device includes a flexible attachment substrate, first and second range detection submodules, an adaptive scheduling unit, a temperature compensation module, a respiratory synchronization correction module, and a wireless communication module. The device can respond in real time to different dose intensities, adaptively switching or merging channels; through respiratory phase recognition and target drift modeling, it projects the acquired dose back to the planning coordinate system, achieving dynamic target dose tracking; and combined with temperature correction and wireless transmission functions, it supports intraoperative data visualization and postoperative assessment. This invention improves the accuracy and safety of radiotherapy dose monitoring, and is particularly suitable for radiotherapy management in areas with significant respiratory-induced drift or near critical organs.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of medical radiotherapy, and particularly relates to a radioactive source personal dose real-time monitoring device and method based on a dual-range adaptive mechanism. BACKGROUND

[0002] In the modern tumor radiotherapy process, how to ensure that the ray dose is accurately and fully concentrated on the lesion target area, while the irradiation on the surrounding normal tissues and key organs is minimized, is the core problem of radiotherapy safety and efficacy evaluation. Although advanced means such as image-guided radiotherapy (IGRT), four-dimensional CT assisted planning, intensity modulated radiotherapy (IMRT) are widely used at present, in actual clinical practice, there are still many technical difficulties that seriously affect the treatment accuracy and individualized safety management, mainly including the following aspects:

[0003] 1. Lack of real-time feedback means of dose during operation, and doctors cannot perceive the irradiation deviation

[0004] At present, most of the radiotherapy relies on the "theoretical dose distribution" set by the planning system, and 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, and plan execution error), it may lead to overexposure, missed exposure and cannot be corrected in time.

[0005] 2. Target area drift induced by breathing causes "planned irradiation ≠ actual irradiation"

[0006] For example, lung cancer, liver cancer, breast cancer and other chest and abdominal tumors, due to the target area position change caused by respiratory motion, the actual tumor area of the patient during radiotherapy drifts from the original planned position, causing part or the whole target area to be inaccurately irradiated, and the adjacent important organs (such as heart, spinal cord, and hepatic portal area) may be "injured" due to drift into the high dose area.

[0007] 3. The precision of traditional dose monitoring methods is insufficient, and the response ability is lagging behind

[0008] The current clinically used thermoluminescence dosimeter (TLD), MOSFET patch, and body surface semiconductor point detector have the following problems:

[0009] Only cumulative dose can be provided, and dynamic changes cannot be shown;

[0010] The dose response range is narrow, and it is easy to saturate at high dose and has low signal-to-noise ratio at low dose;

[0011] It does not have real-time data processing capability and wireless feedback interface, and cannot meet the needs of intraoperative closed-loop control;

[0012] Most monitoring elements need to be taken out and read after the operation, which has a time lag.

[0013] 4. The protection of critical organs relies heavily on doctors' experience and lacks quantitative support.

[0014] When it comes to sensitive structures where the "dosage threshold" needs to be controlled (such as the spinal cord, pulmonary artery, and gastrointestinal tract), clinicians currently often use empirical methods such as "planning gaps" or "setting dose-limiting volumes" before surgery to prevent accidental radiation exposure. However, due to the lack of a real-time, individualized dose monitoring mechanism, if the patient's cooperation is insufficient or the positioning is slightly incorrect, the actual dose coverage area may shift, which can reduce the treatment effect or even cause radiation complications or irreversible damage.

[0015] While current radiotherapy techniques have achieved a high degree of precision, several unresolved clinical issues remain regarding real-time dose visualization, dynamic target alignment, organ protection mechanisms, adhesion adaptability, and system synergy. There is an urgent need to develop a more sophisticated approach.

[0016] It can cover different radiation dose ranges;

[0017] It can achieve dynamic tracking, breathing synchronization, and coordinate projection;

[0018] It can be stably attached to key parts of the human body and supports real-time feedback during surgery;

[0019] A data-driven dose monitoring device and method that can be linked with existing radiotherapy systems (such as TPS, CBCT, OIS). Summary of the Invention

[0020] The purpose of this invention is to provide a device and method for real-time monitoring of individual dose of radiation sources based on a dual-range adaptive mechanism. This invention addresses the aforementioned key clinical problems by providing an integrated real-time dose monitoring device and method for radiotherapy based on dual-range detection, respiratory synchronization, coordinate restoration, temperature compensation, and wireless transmission, thus providing technical support and clinical safety assurance for precise radiotherapy.

[0021] The technical solution adopted in this invention is as follows:

[0022] A real-time personal dose monitoring device for radiation sources based on a dual-range adaptive mechanism includes:

[0023] A flexible adhesive base, made of a flexible, skin-friendly film material, is suitable for radiotherapy patients to apply to the surface of the target area on the chest, abdomen or neck during or after the procedure, and maintains a non-compression fit.

[0024] Multiple dose detection modules are disposed on the flexible adhesive substrate, the dose detection modules including:

[0025] A first-range detection submodule is used for high-sensitivity detection of low-dose radiation signals;

[0026] A second-range detection submodule is used for unsaturated detection of high-intensity radiation signals under high-dose impact.

[0027] An adaptive scheduling unit is connected to the first range detection submodule and the second range detection submodule respectively, and is used to analyze the dose change rate and response trend in real time, and dynamically determine the working state of the above submodules to enable, switch or merge.

[0028] A temperature compensation module, set within a flexible adhesive substrate, is used to collect temperature data of the skin surface and surrounding area, and to perform thermal drift correction on the collected dose signal.

[0029] A wireless communication module is used to synchronously transmit the dose data and temperature information collected by the device to a terminal display device or a clinical data platform;

[0030] A data acquisition and storage module is used to integrate, record, and relay the acquired radiation dose, working channel status, temperature data, and timestamps.

[0031] The flexible adhesive substrate has a radiation-transmitting window in the middle, and its periphery is provided with posture recognition and target area alignment marker structures for position calibration with the radiotherapy equipment imaging system.

[0032] The first range detection submodule and the second range detection submodule are arranged in an alternating manner on the flexible attachment substrate to form a spatially overlapping detection area. The data are fused and calculated by the adaptive scheduling unit to output a weighted dose value.

[0033] The temperature compensation module has multiple miniature thermistor points evenly distributed on the flexible substrate, and the temperature distribution map measured by the module is used to correct the thermal drift error of the photodetector under low dose.

[0034] The target alignment marker structure is a three-point reflective optical marker or an X-ray visible marker, which is compatible with CT or CBCT imaging systems and can be used for automatic position registration in radiotherapy planning systems.

[0035] 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 for achieving respiratory phase synchronization and coordinate correction of dose data, comprising:

[0036] A flexible strain-piezoelectric band is installed in a ring-shaped arrangement around the flexible attachment substrate to output strain electrical signals related to the breathing phase in real time.

[0037] A digital interface chip is used to convert the strain electrical signal into a digital signal and filter out high-frequency noise;

[0038] A phase segmentation algorithm unit is used to calculate the current phase segment of the breath and write the corresponding mark into storage;

[0039] A respiratory synchronization marker register is used to associate each set of sampled dose data with the corresponding respiratory phase segment;

[0040] A target drift correction model is used to project and restore the acquired dose data to the target planning coordinate system based on the pre-stored "phase-target three-dimensional displacement curve" to achieve real-time dose correction under dynamic displacement.

[0041] The "phase-displacement curve" stored in the target area drift correction model is generated from the patient's preoperative four-dimensional CT or CBCT images, and a one-to-one coordinate transformation function is established by manual or algorithmic fitting, which is used to map the dose point corresponding to any respiratory phase to the originally planned irradiation target area.

[0042] A method for real-time monitoring of individual dose from a radiation source includes the following steps:

[0043] S1. Before the operation, obtain the three-dimensional planning image and phase-target displacement curve of the patient's radiotherapy target area, and attach the monitoring device to the skin surface corresponding to the patient's target area;

[0044] S2. Activate the dose detection module and the respiratory synchronization dose marker-correction module to collect radiation dose data and synchronized respiratory phase in real time;

[0045] S3. In the adaptive scheduling unit, determine whether to switch to the second range detection submodule or enable fusion mode based on the dose change rate.

[0046] S4. Write each dose sample value and its corresponding respiratory phase into the respiratory synchronization flag register;

[0047] S5. Call the target area drift correction model to project the coordinates of the corresponding dose point onto the coordinate system of the planned irradiation target area and establish a dose map under respiratory synchronization.

[0048] S6. The processed data is uploaded to the doctor's terminal via the wireless communication module to realize individualized dosage assessment and risk warning during / after the operation.

[0049] Compared with existing technologies, the present invention provides a real-time personal dose monitoring device for radiation sources based on a dual-range adaptive mechanism. It has made systematic technical improvements in four dimensions: monitoring accuracy, response capability, dynamic adaptability, and clinical applicability. It 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.

[0050] Firstly, regarding dose monitoring range and accuracy, existing technologies mostly employ single-range detectors, which either prioritize low-dose sensitivity but are prone to saturation at high doses, or possess high dose tolerance but suffer from high noise and unstable readings in the low-dose region, making it difficult to cover dynamic and complex radiotherapy scenarios. This invention innovatively introduces first-range and second-range detection sub-modules, dynamically activated, switched, or merged by an adaptive scheduling unit. This achieves high-sensitivity, high-resolution monitoring at low doses and avoids signal saturation or data interruption during high-dose impact phases, forming a continuous, stable, and reliable dose tracking path across the entire dose range.

[0051] Secondly, in addressing target displacement caused by respiration, existing technologies mostly rely on preoperative positioning and breath-holding techniques for coarse control, failing to capture intraoperative target displacement caused by respiratory movements. This leads to risks such as irradiation deviation, missed doses, or accidental damage to surrounding organs. This invention integrates a flexible strain-piezoelectric band to sense the patient's respiratory rhythm in real time and combines this 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 current spatial position of the target area in the treatment plan coordinate system, thereby dynamically restoring the true dose distribution and effectively solving the problem of disconnect between dynamic target displacement and dose feedback.

[0052] Regarding data stability and environmental adaptability, traditional photodetectors or semiconductor probes are susceptible to output drift due to factors such as skin temperature fluctuations and radiation thermal effects during use, especially at low doses where errors are easily amplified, affecting the reliability of dose determination. This invention uniformly distributes multiple miniature thermistor points within a flexible substrate to construct a two-dimensional temperature distribution map and performs real-time signal correction based on the device's temperature drift characteristics. This allows the system to maintain excellent output stability and low-dose detection accuracy even under non-constant temperature conditions, enhancing its robustness in complex clinical environments.

[0053] Furthermore, traditional monitoring devices are mostly rigid probes or heavy wearable devices, which are difficult to attach, have large positioning errors, and are often incompatible with intraoperative image registration systems such as CT and CBCT, severely restricting their widespread use in clinical settings. This invention employs a flexible attachment base structure, possessing excellent fit and skin-friendliness, allowing for non-invasive fixation to any location on the patient's chest, abdomen, neck, etc. 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 integrates with existing treatment planning systems, image navigation systems, and radiotherapy information systems, facilitating real-time viewing of dose-displacement-phase information by physicians and creating a complete and traceable individualized treatment record.

[0054] In summary, this invention organically integrates dual-channel fine control of dose acquisition, synchronous marking of respiratory phases, real-time restoration of target area dynamic mapping, and intelligent correction mechanism for temperature interference, constructing a real-time closed-loop radiotherapy dose monitoring platform with high responsiveness, high adaptability, and high integration capabilities. Through synergistic interaction with existing hospital systems such as 4D-CT, TPS, CBCT image registration, and OIS quality control systems, it truly achieves individualized dose visualization and fine-grained control throughout the entire "planning-execution-feedback" process. It demonstrates significant, verifiable, quantifiable, and traceable clinical benefits in preventing radiotherapy irradiation deviations, protecting adjacent critical organs, assessing efficacy, and providing early warning of risks, significantly outperforming existing single-point, single-path, and static traditional technical approaches. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the monitoring device of the present invention;

[0056] Figure 2 This is a schematic diagram of the monitoring device of the present invention;

[0057] Figure 3 This is a schematic diagram of the respiratory synchronization dose marking and correction module of the present invention;

[0058] Figure 4 This is a flowchart illustrating the monitoring method of the present invention;

[0059] Figure 5 This is a flowchart illustrating the respiratory synchronization dose marking and correction module of the present invention.

[0060] In the figure, 1. Flexible attachment substrate; 11. X-ray transmission window; 12. Target area alignment marker 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 band; 92. Digital interface chip; 93. Phase segmentation algorithm unit; 94. Respiratory synchronization marker register; 95. Target area drift correction model. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of this invention clearer, the 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 merely illustrative and not intended to limit the invention.

[0062] See Figure 1 and 2 A real-time personal dose monitoring device for radiation sources based on a dual-range adaptive mechanism includes:

[0063] A flexible adhesive substrate 1, made of a flexible, highly skin-friendly film material, is suitable for application to the target area of ​​the chest, abdomen, or neck during or after radiotherapy, maintaining a non-compression fit. Specifically, the flexible adhesive substrate 1 used in this invention is a single, integrally molded medical-grade elastic film, preferably made of thermoplastic polyurethane (TPU) or medical-grade silicone sheet, possessing good skin-friendliness, breathability, and conformability. Its thickness is controlled between 0.2mm and 0.5mm, sufficient to support the sensing components without causing pressure. The overall shape of the substrate is optimized according to the contour of the human torso, and can be elliptical, oval, or horseshoe-shaped. This substrate structure allows for application to different areas such as the target area of ​​the chest, abdomen, or neck. The application method involves pre-installing disposable medical pressure-sensitive adhesive rings at the edges of the patch for rapid positioning and to prevent displacement.

[0064] Multiple dose detection modules 2 are disposed on the flexible attachment substrate 1, and the dose detection module 2 includes:

[0065] A first-range detection submodule 21 is used for high-sensitivity detection of low-dose radiation signals;

[0066] A second-range detection submodule 22 is used for unsaturated detection of high-intensity radiation signals under high-dose impact.

[0067] The first range detection submodule 21 and the second range detection submodule 22 are arranged in an alternating manner on the flexible attachment substrate 1 to form a spatially overlapping detection area. Their data are fused and calculated by the adaptive scheduling unit 3 and the weighted dose value is output.

[0068] Specifically, the first range detection submodule 21 is a high-sensitivity detector, which uses a PIN photodiode array and is equipped with a low-noise amplification circuit, and is suitable for detecting weak radiation signals as low as 0.001 Gy / min;

[0069] The second range detection submodule 22 is a wide dynamic range detector, which adopts a resistive probe or a small ion chamber structure. It is suitable for operation in high-dose impact scenarios above 1 Gy / min, ensuring unsaturation.

[0070] The two types of sub-modules are embedded under the flexible adhesive substrate 1 in an alternating arrangement, that is, each unit area is simultaneously equipped with the first range detection sub-module 21 and the second range detection sub-module 22, forming a spatially overlapping detection area. This design can achieve high-precision sampling at low doses and avoid saturation or misreading under sudden high dose conditions, thus forming complete dose coverage.

[0071] An adaptive scheduling unit 3 is connected to the first range detection submodule 21 and the second range detection submodule 22 respectively. It is used to analyze the dose change rate and response trend in real time, and dynamically determine the activation, switching, or fusion of the working states of the aforementioned submodules. The adaptive scheduling unit 3 is the core processing control module of this invention, integrating a main control MCU and equipped with an analog-to-digital converter (ADC), a data buffer, and a decision logic module. Its working mechanism is as follows:

[0072] 1. The system defaults to running the first range detection submodule 21;

[0073] 2. The MCU periodically reads its output voltage and calculates the rate of dose change per unit time in real time;

[0074] 3. When the dose rate rises beyond a preset threshold (e.g., 0.2 Gy / min / s), or the output level approaches saturation, the adaptive scheduling unit 3 automatically shuts down the first range detection submodule 21 and activates the second range detection submodule 22.

[0075] 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 fuse their signal outputs by setting a weighting factor (such as W1:W2=0.7:0.3) to achieve smooth switching between ranges;

[0076] 5. Switch the logical record and mark the "working channel status" of the current data frame for subsequent analysis or risk tracking.

[0077] A temperature compensation module, installed within the flexible adhesive substrate 1, is used to collect temperature data of the skin surface and surrounding area, and to perform thermal drift correction on the collected dose signal. The temperature compensation module has multiple miniature thermistor points evenly distributed on the flexible adhesive substrate 1; the temperature distribution map measured by these points is used to correct the thermal drift error of the photodetector under low dose conditions. The miniature thermistor points are NTC thermistors, with 6 to 12 points. Their data are centrally collected by the adaptive scheduling unit 3 and used to construct a two-dimensional temperature distribution map.

[0078] This image can be used for the following correction steps:

[0079] 1. For each dose detection module, its nearest thermal point provides the current temperature value;

[0080] 2. Based on the device's temperature-response drift calibration curve, the MCU automatically adjusts the output of the first range detection submodule 21;

[0081] 3. The correction formula uses first- or second-order polynomial fitting to ensure that the output error is controlled within ±5% in the low-dose range.

[0082] A wireless communication module 7 is used to synchronously transmit the dose data and temperature information collected by the device to the terminal display device or clinical data platform;

[0083] A data acquisition and storage module 6 is used to integrate, record, and relay the acquired radiation dose, working channel status, temperature data, and timestamps. The format is: [timestamp] + [dose of channel 21 in the first range detection submodule] + [dose of channel 22 in the second range detection submodule] + [temperature matrix] + [respiratory phase] + [corrected coordinates]. The data is stored in the FLASH cache and simultaneously uploaded periodically via wireless communication module 7 using BLE5.0 or WiFi to: the clinician's display terminal; the radiotherapy control center server; or a remote cloud storage platform to achieve remote postoperative follow-up and dose analysis.

[0084] A flexible adhesive substrate 1 has a radiation-transmitting window 11 in its center, and a posture recognition and target alignment marking structure 12 is arranged around its periphery for position calibration with the radiotherapy equipment imaging system. The target alignment marking structure 12 is a three-point reflective optical marker or an X-ray visible marker, adapted to CT or CBCT imaging systems, and can be used for automatic position registration in radiotherapy planning systems. Its forms include:

[0085] X-ray visible metal microspheres (tungsten or platinum, 1 mm in diameter).

[0086] The reflective dome structure is suitable for optical camera alignment.

[0087] The three points form a non-collinear equilateral or isosceles triangle.

[0088] After images are acquired using a CBCT or EPD imaging system during the procedure, the algorithm can automatically identify the three-point position and automatically register the coordinate system with the target planning image, which greatly improves the accuracy of radiotherapy target alignment and avoids dose deviation caused by attachment error.

[0089] The radiation transmission window 11 is rectangular, circular, or elliptical, and it is made of a polyimide film with a thickness of less than 50 μm. The radiation transmittance is >90%, ensuring that the radiation can be effectively transmitted and accurately received by the detection module below.

[0090] Further, see Figure 3 and Figure 5 The device further includes a respiratory synchronization dose marking and correction module 9, used to detect changes in the respiratory cycle of the patient's chest or abdomen during radiotherapy, and to achieve respiratory phase synchronization and coordinate correction of dose data, comprising:

[0091] A flexible strain-piezoelectric band 91 is installed in a ring arrangement around the flexible attachment substrate 1 to output strain electrical signals related to the breathing phase in real time.

[0092] A digital interface chip 92 is used to convert the strain electrical signal into a digital signal and filter out high-frequency noise;

[0093] A phase segmentation algorithm unit 93 is used to calculate the current phase segment of the breath and write the corresponding mark into storage;

[0094] A respiratory synchronization marker register 94 is used to associate each set of sampled dose data with the corresponding respiratory phase segment;

[0095] Because the target area in the chest and abdomen shifts significantly with respiration, traditional patch-based dose monitoring suffers from registration drift errors. Therefore, this device incorporates a dedicated respiratory-synchronized dose marking and correction module 9, whose core components are as follows:

[0096] 1) Flexible strain-piezoelectric band 91: The material is PVDF piezoelectric film or conductive fiber, with high strain sensitivity; it is arranged in a ring around the periphery of the patch and distributed along the stress area of ​​the chest and abdomen; it collects the skin stretching changes caused by respiratory movements in real time and outputs strain voltage waveform.

[0097] 2) Digital interface chip 92: It has a high-pass-low-pass filter, analog-to-digital conversion and buffer circuit; the output waveform frame rate is 10Hz and the maximum noise suppression is >40dB.

[0098] 3) Phase segmentation algorithm unit 93: Extracts the main frequency of the waveform using FFT; identifies the current respiratory phase (such as the peak of inhalation, mid-expiration, etc.) through the zero intersection method or amplitude segmentation method; outputs the phase label, which is updated synchronously once per second.

[0099] 4) Respiratory synchronization marker register 94: binds and writes the sampled dose of each frame to the current phase segment; subsequently, dose-phase heatmaps can be constructed based on phase backtracking data.

[0100] 5) Target drift correction model 95: Based on the patient's preoperative 4D-CT or CBCT images; extract the three-dimensional displacement value of the target area under each respiratory phase; establish the "phase-coordinate transformation function" by fitting spline functions or neural networks; at each dose sampling, project the coordinates back to the target planning system to achieve real-time dose reconstruction.

[0101] See Figure 4 A method for real-time monitoring of individual dose from a radiation source, comprising the following steps:

[0102] S1. Obtain three-dimensional planning images and phase-target displacement curves of the patient's radiotherapy target area before surgery, and attach the monitoring device to the skin surface corresponding to the patient's target area.

[0103] S2, activate dose detection module 2 and respiratory synchronization dose marking and correction module 9, to collect radiation dose data and synchronized respiratory phase in real time;

[0104] S3. In the adaptive scheduling unit 3, it is determined whether to switch to the second range detection submodule 22 or enable the fusion mode based on the dose change rate.

[0105] S4. Write each dose sample value and its corresponding respiratory phase into the respiratory synchronization flag register 94;

[0106] S5. Call the target area drift correction model 95 to project the coordinates of the corresponding dose point onto the coordinate system of the planned irradiation target area and establish a dose map under respiratory synchronization.

[0107] S6. The processed data is uploaded to the doctor's terminal via the wireless communication module 7 to realize individualized dosage assessment and risk warning during / after the operation.

[0108] More specifically, clinical methods for real-time monitoring of individual radiation source dose include the following steps:

[0109] Step S1: Preoperative planning and equipment attachment

[0110] ① Use 4D-CT or CBCT to obtain three-dimensional image data of the patient's target area and respiratory cycle information;

[0111] ② Extract the three-dimensional displacement data of the target area under each respiratory phase segment and establish a "respiratory phase-displacement curve";

[0112] ③ Clean the patient's skin surface and select a flexible adhesive substrate 1 that matches the target area;

[0113] 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).

[0114] ⑤ Adjust the device to align with the center of the radiation, so that the radiation passes through window 11 and is located at the projection point of the target center;

[0115] ⑥ Complete three-point registration in the CT or CBCT imaging system using marker point 12 to ensure that the device coordinates are consistent with the treatment plan coordinates.

[0116] Step S2: Activate each functional module and initialize its state.

[0117] ① Turn on the power to the monitoring device and activate the dose detection module 2;

[0118] ② Simultaneously activate the respiratory synchronization dose marking and correction module 9, including the flexible strain-piezoelectric band 91 and the digital interface piece 92;

[0119] ③ Adaptive scheduling unit 3 begins initialization testing of the first / second range submodules and reads the baseline signal;

[0120] ④ The temperature compensation module reads the values ​​of each thermistor and generates an initial temperature distribution map;

[0121] ⑤ The data acquisition module synchronously records the timestamp and begins preparation for cyclic sampling.

[0122] Step S3: Intraoperative radiotherapy real-time dose acquisition and range switching

[0123] ①After the radiation source is turned on, the dose detection module receives the radiation signal in real time;

[0124] ② By default, the first range detection submodule 21 is used for low-dose, high-sensitivity data acquisition;

[0125] ③ If the dose rate change is detected to exceed the set threshold (e.g., >0.3Gy / min / s), or the signal approaches saturation, the adaptive scheduling unit 3 will automatically switch to the second range detection submodule 22 or enable fusion acquisition;

[0126] ④ The dose data, working channel status, respiratory phase label and timestamp collected at the same time are stored in the cache area.

[0127] Step S4: Real-time analysis and synchronization of respiratory phases

[0128] ① The breathing synchronization module captures the movement of the thoracic cavity or abdominal wall through the flexible strain-piezoelectric band 91 and extracts the breathing waveform;

[0129] ② The current respiratory phase is calculated using the phase segmentation algorithm unit 93 and identified as "peak of inspiration", "mid-inspiration" or "pre-expiratory phase";

[0130] ③ Write the current respiratory phase segment number into the respiratory synchronization flag register 94;

[0131] ④ Bind the phase segment number to the corresponding dose data to achieve synchronization between each frame of dose data and respiratory status.

[0132] Step S5: Target area drift correction and coordinate mapping

[0133] ① Call the pre-set "respiratory phase-three-dimensional displacement curve" and extract the target displacement vector under the current phase using the target drift correction model 95;

[0134] ② Map the collected dose point locations to the treatment plan coordinate system;

[0135] ③ Under dynamic respiratory displacement conditions, three-dimensional coordinate correction is performed on all dose points to construct real-time dose heatmap and cumulative dose map;

[0136] ④ The dose data is matched with the displacement coordinates in real time to prevent clinical errors such as "dose blanking" or "insufficient irradiation" caused by the displacement of the body surface position.

[0137] ⑤ Generate a corrected "dose-position map under respiratory synchronization" for subsequent clinical evaluation or automatic control interface linkage.

[0138] Step S6: Real-time data integration and wireless upload

[0139] ① The data acquisition and storage module 6 packages the complete information of the current frame, including: dose data (first / second sub-module), working channel status (main channel, fusion, switching marker), respiratory phase label, temperature value distribution, corrected coordinates and timestamp;

[0140] ② All data is cached in structured frame format to the built-in Flash memory chip;

[0141] ③ Every 5 seconds or after a set sampling period, the data is sent to the doctor's terminal or the hospital's clinical data platform via the wireless communication module 7;

[0142] ④ The data platform can display the actual received dose, cumulative dose change trend, respiratory induction deviation, and risk warning information of the current target area in real time.

[0143] Step S7: Postoperative individual dose analysis and closed-loop management

[0144] ①After radiotherapy, the doctor's terminal can access the patient's complete dose monitoring records to review the radiotherapy period: dose curve, respiratory phase variation, dose gaps or overlaps, and temperature abnormality alarms;

[0145] ② By comparing the original planned dose distribution, the system automatically assesses the actual target area dose achievement rate. If there are areas with insufficient dose, the doctor can decide to provide supplementary treatment or adjust the plan.

[0146] ③ Data is synchronized to the patient medical record system and radiotherapy quality control database to support the optimization of subsequent treatment courses;

[0147] ④ If the device enables the breathing training assistance interface (such as external monitoring and synchronous feedback), it can also be used for preoperative training or intraoperative interactive control to improve patient cooperation.

[0148] Furthermore, in clinical radiotherapy, especially for patients undergoing abdominal / pelvic radiotherapy (such as liver cancer, pancreatic cancer, uterine cancer, etc.), differences in the state of the intestines, stomach, or bladder contents before surgery can cause inconsistencies in the radiation attenuation path, leading to dose deviations. During actual treatment, doctors cannot know in real time whether the patient has eaten, drunk, or defecated, and traditional dose detection devices are completely unable to identify or compensate for this, which is one of the important sources of clinical dose uncertainty.

[0149] In this embodiment, to address the problem of inconsistent radiation attenuation paths caused by changes in the state of the contents inside the patient's abdominal cavity during radiotherapy, which leads to distortion in dose monitoring, this 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.

[0150] The core idea of ​​this mechanism is to indirectly infer the changing state of the contents inside the body cavity through detailed analysis of the abdominal surface deformation patterns during respiration, thereby correcting the credibility weight of the real-time acquired radiation dose data. This method does not rely on new hardware or direct image judgment, but fully utilizes the data output from the existing flexible strain-piezoelectric breathing belt in the original scheme of this invention, combined with intelligent algorithm modules for reasoning and analysis.

[0151] In practical applications, during radiotherapy, this breathing band is attached to the periphery of the abdomen to record the abdominal wall expansion and contraction signals caused by respiratory movements in real time. 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 time distribution of inhalation and exhalation, waveform symmetry, and the rhythmic stability between continuous waveforms.

[0152] By comparing these respiratory waveform features with the preoperatively established "fasting reference waveform model," the system can determine whether the patient is currently in a normal emptying state, a state with increased contents, or a fasting state. For example, if it is found that the abdominal wall expansion amplitude decreases during inspiration, the waveform top flattens, the cycle lengthens, and the difference between the previous and subsequent cycles increases, the system can infer that the patient has a large amount of abdominal contents, which may affect the consistency of the radiation propagation path.

[0153] Based on this inference, the system assigns a confidence weight factor corresponding to the state to the radiation dose data collected in the current frame. If it is determined that "there is too much content," the dose value of that frame will be reduced, or it will be marked as "possibly affected" in the doctor's terminal. If it is determined that "empty state," no correction will be made, and the original output of the data will be maintained.

[0154] This correction mechanism remains fully compatible with the original scheme's "respiratory synchronization marker" and "coordinate restoration correction" modules, without altering the original data structure or affecting the respiratory phase marking function. Instead, by enhancing the perception of internal physiological changes, it makes the projection of each dose point in the three-dimensional atlas more realistic and clinically significant.

[0155] Ultimately, when doctors review dose data graphs during or after surgery, they can simultaneously see three labels: "dose value," "spatial location," and "current contents status," and use this information to determine whether the dose data can be used for assessment, whether repositioning is necessary, or to warn of potential irradiation deviations.

[0156] This mechanism is particularly suitable for precision radiotherapy of abdominal and pelvic target areas such as liver cancer, pancreatic cancer, and uterine cancer. It provides a clever, non-invasive compensation path that can be implemented based on existing structures, filling the technological gap where traditional patch dose monitoring cannot detect the "internal state".

[0157] The following are several typical clinical application cases based on the "Real-time Personal Dose Monitoring Device for Radiation Sources with Dual-Range Adaptive Mechanism" of this invention, covering representative tumor radiotherapy scenarios in high-risk, highly dynamic variation areas such as the chest, abdomen, and neck, demonstrating the practical application value, technical advantages, and key role of this solution in precision treatment:

[0158] Case 1: A patient undergoing adjuvant radiotherapy after left-sided breast cancer surgery (near the heart)

[0159] Patient characteristics: 47-year-old female who underwent breast-conserving surgery and left breast tumor removal.

[0160] Treatment challenges: The left breast target area is close 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 target the myocardium.

[0161] 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 under the "deep inspiration and breath-hold" state to restore the dose coordinates to the target position under deep inspiration.

[0162] Application results: Through verification via hospital DICOM-RS data docking, after comparing real-time monitoring data with the treatment plan, MHD decreased by approximately 0.8 Gy; PTV coverage remained >96.5%, confirming that the target area was not missed due to breath-hold displacement;

[0163] Case 2: A patient with liver cancer undergoing radiotherapy in the diaphragmatic dome region (moving significantly up and down with breathing).

[0164] Patient characteristics: 62-year-old male with a tumor in the right lobe of the liver, in the top region of the diaphragm, and mild emphysema.

[0165] Treatment challenges: The tumor moves up and down by 1.8 cm with breathing, and conventional radiotherapy carries the risk of off-target effects.

[0166] Device usage: Attached to the skin of the upper right abdomen; the breathing belt monitors the respiratory phase in real time; each frame of dose is matched with the "phase-displacement model" and automatically performs three-dimensional coordinate reconstruction.

[0167] Application results: Validated by CBCT image registration and dose fusion software, the D95 difference in the target area decreased from ±7.4% to ±1.9%; the Dice index of the overlapping area increased to 0.92 (better than 0.77 without correction).

[0168] Case 3: Patient with small cell lung cancer near the hilum (target area adjacent to the main blood vessel)

[0169] Patient characteristics: 55-year-old male, small cell lung cancer, target area close to the pulmonary artery;

[0170] Treatment challenges: The pulmonary artery and aortic arch are highly susceptible to accidental irradiation damage;

[0171] Device usage: The device is attached to the right side of the midline of the chest; dynamic dose acquisition and dose slope change detection to identify sudden dose peaks; high-speed switching to the second range submodule for stable operation to avoid saturation; temperature compensation mechanism to correct thermal drift.

[0172] Application effects: Automatically identifies high-dose impact segments and maintains data continuity; compares hospital TPS plans with actual curves, identifies a 10-second high-dose segment error, and corrects the plan; consistent with data exported from the Record & Verify (R&V) system, providing clinical audit traceability.

[0173] Case 4: Patient undergoing radiotherapy to the target area of ​​the laryngeal cancer stump after surgery (complex structure and narrow target area)

[0174] Patient characteristics: A 60-year-old male who underwent radiotherapy after partial laryngectomy;

[0175] Treatment challenges: The target area is located in the center of the neck, which has a dense structure, thin skin, and strong respiratory / swallowing interference;

[0176] 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 removed to generate a continuous effective dose spectrum.

[0177] Application results: After the monitoring device was activated, 15 dose jump frames caused by swallowing were effectively eliminated; the final frame effectiveness rate was 98.6%, which was used for subsequent dose reconstruction; after loading the output data of this device into the hospital's Pinnacle / Eclipse system, the heat map matching degree was >94%.

[0178] Case 5: Patients with recurrent mediastinal tumors requiring re-irradiation (high risk of cumulative dose exceeding the target)

[0179] Patient characteristics: A 69-year-old female who had previously received chest radiotherapy and has now been found to have a focal recurrence of the paramedian lesion.

[0180] Treatment challenges: The dose to the original irradiated area is nearing criticality, and the permissible dose for OARs (such as the spinal cord) is decreasing; the radiotherapy plan needs to accurately calculate the "remaining available dose";

[0181] Device usage: A real-time monitoring device is attached during re-irradiation; all actual doses are mapped by coordinates and overlaid with historical data; the system can calculate a cumulative dose cloud map and provide organ over-threshold alarms;

[0182] Application effects: Spatially overlaps the actual intraoperative dose with the historical planned dose; determines that the actual cumulative dose to the spinal cord does not exceed the critical threshold of 45 Gy; and achieves quantitative verification by comparing the DVH curve output by the hospital radiotherapy quality management system (OIS).

[0183] In summary, this invention has demonstrated stable and verifiable clinical benefits in multiple typical high-risk radiotherapy scenarios, achieving a leap from "data monitoring" to "dynamic guidance + real-time safety control," and possesses significant clinical promotion value and technological substitution potential.

[0184] 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 within the protection scope of the present invention.

Claims

1. A device for real-time monitoring of personal dose of radioactive source based on dual-range adaptive mechanism, characterized in that, The device comprises: a flexible attaching base (1) made of bendable and high skin-friendly film material, which is suitable for attaching to the surface of the target area on the chest, abdomen or neck of a patient during or after radiotherapy and keeping a non-compressive fit; a plurality of dose detection modules (2) arranged on the flexible attaching base (1), wherein the dose detection module (2) comprises: a first range detection submodule (21) for high-sensitivity detection of low-dose radiation signals; a second range detection submodule (22) for unsaturated detection of high-intensity radiation signals under high-dose impact; an adaptive scheduling unit (3) connected with the first range detection submodule (21) and the second range detection submodule (22), respectively, for real-time analysis of dose change rate and response trend, and dynamic decision of the working state of the above submodules; a temperature compensation module arranged in the flexible attaching base (1), for collecting temperature data of the skin surface and the surrounding area, and performing thermal drift correction on the collected dose signals; a wireless communication module (7) for synchronously transmitting 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) for unified integration, recording and relay processing of the collected radiation dose, working channel state, temperature data and time stamp; a radiation transmission window (11) is arranged in the middle of the flexible attaching base (1), and a posture recognition and target area alignment mark structure (12) is arranged around the radiation transmission window (11), for position calibration with the imaging system of the radiotherapy equipment.

2. The monitoring device according to claim 1, wherein: the first range detection submodule (21) and the second range detection submodule (22) are arranged in an interleaved manner on the flexible attaching base (1) to form a spatially overlapped detection area, and the data thereof is fused and calculated by the adaptive scheduling unit (3) and outputted as a weighted dose value.

3. The monitoring device according to claim 1, wherein: the temperature compensation module is uniformly arranged with a plurality of micro thermistors on the flexible attaching base (1), and the temperature distribution map measured thereby is used for correcting the thermal drift error of the photodetector at low dose.

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

5. The monitoring device of claim 1, wherein: The device further comprises a breathing synchronous dose mark and correction module (9) for detecting the breathing cycle change of the chest or abdomen of the patient during radiotherapy, and realizing breathing phase synchronization and coordinate correction of the dose data, which comprises: a flexible strain-piezoelectric strip (91) arranged in a ring shape on the periphery of the flexible attaching base (1), for real-time output of strain electrical signals related to the breathing phase; a digital interface sheet (92) for converting the strain electrical signals into digital signals and filtering high-frequency noise; a phase segmentation algorithm unit (93) for calculating the phase segment of the current breathing and writing the corresponding mark into the storage. a breathing synchronization marker register (94) for associating a corresponding breathing phase segment with each set of sampled dose data; a target drift correction model (95) for projecting the collected dose data back to the target planning coordinate system based on a preoperatively stored "phase-target 3D displacement curve" to achieve real-time dose correction under dynamic displacement.

6. The monitoring device of claim 5, wherein: the "phase-target 3D displacement curve" stored in the target drift correction model (95) is generated from a preoperative 4D CT image of the patient and a one-to-one coordinate conversion function is established by manual or algorithmic fitting to map dose points corresponding to any breathing phase to the original planned irradiation target.

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