199 results about "Dose distribution" patented technology

The invention discloses a BNCT dose calculation method, which comprises the following steps: S1, constructing a voxel model, initializing one or more particles in a simulation system, and respectively acquiring the initial position, energy and movement direction of each particle; s2, adaptively selecting a Monte Carlo particle tracking algorithm and a flux counting mode based on the region where the particles are located and the energy of the particles; s3, repeating the step S2 until the particles leave the simulation system or are killed when meeting a truncation condition; and S4, cumulatively calculating dose distribution. Through the BNCT dose calculation method, the Monte Carlo particle transport simulation time is greatly shortened, the BNCT dose calculation efficiency is optimized, and the method is suitable for rapid and high-precision radiation dose simulation under a BNCT complex tissue structure.

The invention discloses an ultra-high dose rate radiotherapy plan optimization system based on compensator modulation, and relates to the technical field of radiotherapy. A data acquisition module is used for acquiring medical image data of a patient and receiving a clinical target; the clinical target comprises a target region prescription dose, an organ-endangering limit and a minimum dose rate threshold value required for triggering and maintaining a FLASH effect; and the FLASH biological effect evaluation module is used for calculating FLASH biological effective dose distribution corresponding to the physical dose distribution through an embedded biological effect model based on the input physical dose distribution and dose rate distribution. According to the method, the physical dose is converted into the accurate FLASH biological effective dose through the improved linear quadratic model embedded with the FLASH correction factor, the target tumor killing effect is guaranteed, normal tissue protection is enhanced with the help of the tissue differentiation correction factor, the industrial pain point that the physical dose reaches the standard but the biological effect does not reach the expectation is effectively solved, and the application prospect is wide. And the treatment plan better meets the clinical curative effect and safety core requirements.

The invention relates to a self-adaptive radiotherapy plan determination method, a self-adaptive radiotherapy system and a storage medium. The method comprises the following steps: acquiring a current region-of-interest segmentation result and current image features corresponding to a current image of an object; according to the segmentation result of the current region of interest and the current image features, candidate radiotherapy plans are selected from a plan library of the object, and the plan library comprises historical images of the object and corresponding historical radiotherapy plans; calculating a calculated dose distribution corresponding to the current image based on parameters in the candidate radiotherapy plan; determining the applicability of the candidate radiotherapy plan for the current image according to the calculated dose distribution, the segmentation result of the current region of interest and the features of the current image; and the target radiotherapy plan for the current image is determined based on the applicability, so that the generation efficiency and effectiveness of the adaptive radiotherapy plan are improved.

The invention discloses a U-shaped groove grating ion beam etching method based on a mask shadow effect, and relates to the technical field of U-shaped groove etching, and the method comprises the steps: placing a substrate with a photoresist grating mask in an inclined manner, and enabling an ion beam to bombard the photoresist grating mask in an inclined incidence manner; through a shadow effect generated by a photoresist grating mask on an ion beam, the etching dose distribution of different areas on the surface of a substrate is regulated and controlled, so that the etching dose of the central area of the groove bottom is greater than that of the areas on the two sides, and the U-shaped groove with a smooth and gradually-changed bottom contour is directly etched and formed. By constructing the smooth transition U-shaped groove bottom structure, sharp edges and corners are thoroughly eliminated, and the phenomenon of electric field concentration is remarkably relieved, so that the damage risk under high-power laser irradiation is effectively reduced, the stability of the grating in an extreme environment is improved, and the service life of the grating in the extreme environment is prolonged.

The invention relates to the technical field of radiotherapy dose analysis, in particular to a radioactive cardiotoxicity prediction system based on multi-modal dynamic fusion and a quantitative evaluation method. According to the system, medical images, radiotherapy plans and clinical parameters are acquired through the multi-modal data acquisition module; the image preprocessing and three-dimensional reconstruction module processes the image data and reconstructs a heart model containing a substructure; the dynamic dose module is combined with the four-dimensional respiratory gating image and the dose matrix to generate time sequence dose distribution; the feature fusion and prediction module extracts multi-modal features, performs calculation by using a graph convolutional network, a long-short term memory network and an attention mechanism, and outputs a cardiotoxicity risk quantitative index; and finally generating a heart substructure level risk thermodynamic diagram and a structured report. According to the method, dynamic dose modeling, heart substructure level refined analysis, multi-source information fusion and individualized prediction are realized, and the accuracy, interpretability and clinical auxiliary decision-making value of cardiac toxicity risk assessment are remarkably improved.

The invention relates to the technical field of medical treatment, in particular to a deformation registration method and system, a self-adaptive treatment planning method and a treatment planning system which are used for improving the accuracy of image deformation registration, and the method comprises the steps: obtaining a plan image, a fractional image and dose distribution data corresponding to an initial treatment plan of a patient; inputting the plan image, the graded image and the dose distribution data corresponding to the initial treatment plan of the patient into a trained deformation registration model, performing deformation registration on the graded image and the plan image, and outputting a deformation field; wherein the trained deformation registration model is obtained based on dose distribution consistency loss training between dose distribution data corresponding to the initial treatment plan and deformation dose distribution data corresponding to the deformation field.

The invention discloses an AI auxiliary radiotherapy dose intelligent optimization device, which comprises a multi-modal image fusion module, a dose distribution prediction module, a dynamic adaptive optimization module and a prognosis model integration module, and is characterized in that the multi-modal image fusion module is used for aligning anatomical features of different images, eliminating respiratory motion artifacts and predicting the dose distribution of the different images; the dose distribution prediction module is used for rapidly predicting radiotherapy dose distribution based on anatomical features and historical data, the dynamic adaptive optimization module is used for monitoring anatomical changes in real time and dynamically adjusting a dose plan, and the prognosis model integration module is used for quantifying correlation between dose distribution and radioactive injury risks. High-precision alignment and respiratory motion artifact elimination of an anatomical structure are achieved through the multi-modal image fusion module, three-dimensional dose calculation is rapidly and accurately conducted through the dose distribution prediction module, organ displacement and deformation are effectively coped with through the dynamic self-adaptive optimization module through a real-time image monitoring and reinforcement learning algorithm, and the accuracy of the three-dimensional dose calculation is improved. And the prognosis model integration module constructs an individualized risk prediction model.

The invention provides a proton dose distribution determination method and device based on a graphics processor, which can be applied to the technical field of medical radiation dose calculation. The method comprises the following steps: calculating pencil beam tracks of a plurality of pencil beams; obtaining respective dose nuclear parameters of the pencil beam at a plurality of intersection points; according to the radiation field dose truncation radius, voxels of interest are determined from tissue voxels in the tissue voxel grid, and the radiation field dose truncation radius represents the upper limit value of the acting distance of all pencil beams in one radiation field to generate remarkable contribution to dose distribution in the transverse direction; calling a plurality of threads to execute dose calculation tasks of the plurality of voxels of interest in parallel based on the respective dose kernel parameters of the plurality of intersection points to obtain voxel deposition doses of the voxels of interest; and determining a dose distribution result related to the specified tissue according to the voxel deposition doses of the plurality of voxels of interest.

The invention provides a medical linear accelerator virtual source model optimization method which is characterized by comprising the following steps: constructing a virtual source model and inputting initial configuration parameters; obtaining simulated dose distribution data of a typical irradiation regular field based on the model; vertically irradiating on the standard water model through a medical linear accelerator to obtain corresponding measurement dose distribution data; performing priority evaluation and sorting on part of parameters of the virtual source model, and performing iterative adjustment according to the priority until the simulation and measurement dose distribution difference is within a preset range; and inputting the parameters after iteration is completed into the virtual source model to obtain an optimized model. According to the method, full-process automatic optimization of the virtual source model can be achieved, manual intervention is remarkably reduced, the labor cost is saved, the modeling precision and efficiency are greatly improved, and the method is suitable for an efficient and high-precision source modeling process under a complex structure.

A radiation exposure dose management apparatus according to an embodiment is a radiation exposure dose management apparatus that manages a radiation dose received by a subject and includes processing circuitry configured: to obtain image data of the subject; to segment the image data in accordance with organs of the subject; to generate a voxel radiation dose distribution map indicating a radiation exposure dose of each of the voxels on the basis of a specific radiation exposure dose model and the image data; and to calculate a radiation exposure dose of each of the organs on the basis of the segmented image data and the radiation exposure dose of each of the voxels within the generated voxel radiation dose distribution map.

The invention provides a non-uniform ion implantation process monitoring method based on template matching image recognition, and the method comprises the steps: 1, carrying out the to-be-monitored non-uniform ion implantation of a wafer, carrying out the modeling according to the measurement data of the wafer, and obtaining a template used for monitoring the dose / resistance distribution of the non-uniform ion implantation; step 2, carrying out resistance measurement on the batch of wafers after the non-uniform ion implantation, and drawing a resistance distribution diagram according to the coordinates and the resistance values of the measurement point positions; and 3, carrying out image identification comparison operation on the template obtained in the step 1 and the resistance distribution diagram obtained in the step 2 to obtain a similarity score, and carrying out statistical process control and control on the similarity score. Abnormalities such as deviation and rotation of dose distribution patterns of the non-uniform ion implantation process are effectively captured, and monitoring of the non-uniform ion implantation process is achieved.

A rapid verification method for adaptive radiotherapy dose consistency in the TOMO system is disclosed, relating to the field of medical information technology, particularly TOMO radiotherapy information processing. The method includes: acquiring flux distribution data and the original region of interest (ROI) from the original radiotherapy plan; projecting the ROI onto the flux projection space based on the beam geometry parameters of the original radiotherapy plan, and establishing a mapping relationship as a reference index; acquiring the target ROI for the adaptive radiotherapy phase; updating the mapping relationship based on the flux distribution data and the target ROI, and using the mapping relationship as the target index; detecting the data consistency between the target index and the reference index, and determining the dose distribution change information of the target object. This application solves the technical problems in existing technologies where adaptive radiotherapy dose consistency verification relies on a high-load dose calculation engine for data reprocessing, resulting in large amounts of computational data, high system response latency, and inability to meet the timeliness requirements for online verification.

A boron dose measurement system, method and apparatus. The system is provided with a first detection apparatus (10), a second detection apparatus (20) and a boron dose measurement apparatus (30), wherein the first detection apparatus (10) detects gamma rays in a target region, in order to obtain first boron measurement information, the first boron measurement information comprising energy spectrum information of the gamma rays; the second detection apparatus (20) detects the gamma rays in the target region, in order to obtain second boron measurement information, the second boron measurement information comprising position information of the gamma rays; the second detection apparatus (20) and the first detection apparatus (10) synchronously perform measurement; and the boron dose measurement apparatus (30) can determine a boron dose distribution in the target region on the basis of the energy spectrum information and the position information of the gamma rays that are obtained by means of synchronous measurement. A boron dose distribution in a target region can be accurately obtained, and the obtained boron dose distribution can meet the requirements for online boron dose monitoring.

An automated radiotherapy planning system for generating a deliverable radiotherapy plan (31) for a patient, to be delivered by a predefined radiotherapy delivery system, the system is configured to segment a target volume and one or more organs at risks in a 3D medical image of the patient, generate a prediction of a 3D volumetric dose distribution, generate the deliverable radiotherapy plan (31) and send the deliverable radiotherapy plan (31) to a predefined radiotherapy delivery system for final verification and execution.

The invention relates to a computer-implemented method for determining spatially resolved radiation load information of a patient when conducting an examination with an imaging X-ray apparatus having an X-ray radiator for outputting an X-ray field for conducting the examination, wherein patient input dose information is determined for determining the radiation load information, wherein the pre-dose information is determined in the case of use of a matching filter arranged between the patient and the X-ray radiator, which causes a non-uniform dose distribution in a plane perpendicular to a central ray of the X-ray field, the pre-dose information describing a uniform distribution of the X-ray dose acting on the patient without the matching filter; dose distribution information is calculated using the pre-dose information by means of a filter model, which describes at least the dose distribution of the X-ray dose acting on the patient in the part of the X-ray field covered by the matching filter; and the patient input dose information is determined using the dose distribution information.

A moving body tracking device obtains the position of a tracking object 55, and generates a signal for permitting irradiation of a target 50 with radiation when it is determined that the tracking object 55 exists inside a gate range. In the moving body tracking device, the gate range varies between timing when the tracking object 55 enters the inside from the outside of the gate range and timing when the tracking object exits from the inside to the outside. Accordingly, provided are a moving body tracking device and a radiation irradiation system with which it is possible to suppress a change in the dose distribution and a decrease in irradiation efficiency due to the influence of latency.

This application discloses a spatial segmentation radiotherapy guidance method and system based on target immune region activation, relating to the field of digital electrophysiological data processing. The method achieves three-dimensional visualization of metabolic activity and immune response through multimodal fusion of spectral CT / functional magnetic resonance imaging and ResNet radiomics feature extraction, which significantly improves the recognition accuracy compared to anatomical target volume. Furthermore, the immune thermogram generated by the XGBoost model and SAMed-2 segmentation markers can accurately locate highly immune-responsive voxels, and the Monte Carlo simulation gradient dose distribution ensures that the dose intensity in the immune-activated region is several times that of the conventional region while protecting the inactive region. The XGBoost model training of this application can dynamically adjust the dose hotspot according to the patient's specific immune characteristics, so that the radiation can accurately and sufficiently reach the region in the tumor area that is most capable of activating the immune system.

This application relates to a method, apparatus, and computer-readable storage medium for determining beam distribution. For a beam to be modeled, at least two reference directions are determined based on a measured dose distribution; and a target beam distribution of the beam is determined based on at least two reference beam distributions corresponding to the at least two reference directions. This solves the problem of low beam modeling efficiency, improves the speed of modeling calculation, and is applicable to a wider range of application scenarios.

A method is provided that can correct the focal position even when the height position distribution has changed due to irreversible deformation of a sample caused by irradiation with a charged particle beam. [Configuration] A charged particle beam writing method according to one aspect of the present invention is characterized by comprising the steps of: determining a height change distribution, which defines the height change from the height position of the sample before irradiation caused by irreversible deformation of the sample at each position on the sample at the time of irradiating the sample with a charged particle beam, the sample being irreversibly deformed depending on the irradiation dose distribution of the charged particle beam; correcting the focal position of the charged particle beam when irradiating the sample with the charged particle beam based on the height change distribution; and writing a pattern on the sample with the charged particle beam having the corrected focal position.

The application discloses a reflection type volume grating uniformity improving device and method, which adopts a double-system cooperative structure of axial exposure dose compensation and double-beam interference exposure. The axial exposure dose compensation system compensates the non-uniform axial exposure dose distribution caused by energy attenuation through laser irradiation of a photosensitive wave band of a recording medium and multi-axis rotation of the recording medium. The double-beam interference exposure system generates two collimated coherent lights with adjustable polarization states and powers by using laser of a high-transmittance wave band of the recording medium and a polarized beam splitter, and accurately controls the interference angle by adjusting the mirror posture, so that the high-contrast grating structure is written in the recording medium subjected to the axial exposure dose compensation. The application can effectively solve the non-uniform exposure dose distribution problem caused by laser energy attenuation in the traditional preparation process, thereby guaranteeing the consistency of the axial performance of the volume grating, and effectively promoting the development of the fields of high-performance laser beam combination, pulse compression and optical communication filter which need high-uniformity volume grating.

The invention provides a rapid Monte Carlo dose calculation method based on statistical uncertainty perception noise reduction and application, and the method comprises the steps: carrying out the Monte Carlo dose simulation of a low particle number, and obtaining the middle rough dose distribution containing random noise and a corresponding voxel-level statistical uncertainty distribution diagram; acquiring an anatomical structure image of a patient, performing normalization processing and registration processing on the anatomical structure image, the middle rough dose distribution and the corresponding voxel-level statistical uncertainty distribution diagram, and constructing three-channel input data; the three-channel input data is input into a pre-constructed and trained statistical uncertainty perception denoising network model, the network model adopts a dual-path cavity convolution fusion architecture, and local features and global context features are extracted and fused; and the network model outputs denoised high-precision dose distribution as a final Monte Carlo dose calculation result. According to the method, the efficiency and the accuracy of radiotherapy plan design are remarkably improved.

The invention relates to the technical field of sewage treatment, and discloses ultraviolet disinfection equipment for sewage treatment, which comprises a horizontally arranged reaction cavity and a plurality of quartz sleeves. In the flowing process of the sewage in the reaction cavity, the sewage is continuously directly irradiated and irradiated by the reflected ultraviolet rays. Ultraviolet disinfection destroys the DNA / RNA structure of the microorganisms, so that the microorganisms lose the reproductive capacity, and the purposes of disinfection and sterilization are achieved. Purified water fully disinfected by ultraviolet rays is discharged from a water outlet pipe at the other end of the reaction cavity, so that the whole disinfection process is completed. The combination of the ultraviolet lamp tubes arranged circumferentially and the tubular reflectors forms an efficient ultraviolet radiation field, so that ultraviolet energy is fully utilized, and energy waste is reduced. The reflector effectively makes up the irradiation blind area between the lamp tubes, and ensures the uniformity of dose distribution on the cross section of water flow.

The invention discloses a real-time positioning method for a tumor target region and a gold label implant, and belongs to the technical field of tumor localization, and the method specifically comprises the following steps: implanting a gold label in a tumor region, constructing a gold label-tumor dynamic model through CT, and obtaining a respiratory phase feature vector; realizing space matching of the two-dimensional projection and the three-dimensional model by using an improved hybrid registration algorithm, and obtaining a tumor compound displacement vector; establishing a respiration-displacement correlation model through time sequence alignment, generating a tumor movement map containing a real-time position and a predicted trajectory, and updating the reference coordinate system; establishing a rigid safety boundary based on a gold label, analyzing soft tissue texture and a prediction trajectory in combination with a convolutional neural network to generate an elastic treatment boundary, and dynamically adjusting a dose weight of a non-label area; and finally, submillimeter-level dynamic tracking is executed through a multi-leaf collimator. The problems of tumor motion uncertainty and individual deformation difference are solved, and the target area coverage precision and the dose distribution reasonability are improved.

The invention discloses a PET imaging device for multi-radiation-field particle therapy, PET equipment and a therapy system. The PET imaging device comprises: an identification unit configured to identify one or more time intervals of each radiation field according to time distribution characteristics of collected single event data, each time interval corresponding to a particle beam delivery state; the coincidence processing unit is configured to perform coincidence processing on the single event data to generate coincidence event data; and the reconstruction unit is configured to perform image reconstruction on the coincidence event data in the identified time interval of each radiation field to obtain a reconstructed image corresponding to each radiation field. Through intelligent identification of time distribution characteristics and a partition reconstruction strategy, the problem of serious aliasing of PET signals in a multi-radiation-field delivery mode is solved, and accurate extraction of independent dose distribution of each radiation field and image reconstruction are realized.

This invention provides a proton imaging method and imaging device, applicable to the fields of proton imaging technology and signal processing technology, particularly in the field of particle radiation imaging technology. The method includes: determining a virtual source position based on an initial two-dimensional dose distribution of a proton beam acquired without an imaging object; obtaining multiple sub-beam propagation paths from the virtual source position to the multiple predetermined sub-beam center positions based on the virtual source position and multiple predetermined sub-beam center positions on a predetermined plane; obtaining sub-beam data pairs corresponding to the sub-beam propagation paths and the two-dimensional dose distribution based on the two-dimensional dose distribution and the lateral distribution components determined along the sub-beam propagation paths; obtaining multiple water equivalent path lengths corresponding to at least one projection angle through an iterative algorithm based on the multiple sub-beam data pairs corresponding to at least one projection angle; and performing image reconstruction based on the multiple water equivalent path lengths corresponding to at least one projection angle to obtain a target image of the imaging object.

The present invention relates to the field of medical therapy of lesions detrimental to a body. The system is capable of treatment with a non-invasive, ionizing kV energy radiation source. Locally focused energy can be used to definitively treat, or as an adjuvant to enhance immune modulators, to eliminate tumors. Distributed external beam entry points produce a significant advantageous dose profile at depth as intersecting beams accumulate in a narrow focus to treat a selected volume. Targeted disease may have enhanced sensitivity to the radiation by taking up an ionizing-radiation, treatment-localizing agent. This increases the effectiveness of an energy dose in the lesion. The pattern of beam output is effectively directed towards a desired location and kV x-rays traveling towards undesired locations, such as healthy tissue, are quenched. Targeting a lesion within the body with volumetrically discrete energy dose deposition can beneficially impact harmful lesions. Aiming the beam at a pathologic target is done while moving an x-ray source mechanically around a patient to distribute surface dose. The purpose of the focused energy deposition is to destroy and disable pathologic physiology, such as malignant masses. More specifically this invention relates to a system, which optimizes delivery of ionizing kV beams to a lesion alone or one containing treatment-localizing agents in higher concentration than the surrounding normal tissues. Thereby an optimal delivery of ionizing radiation becomes more destructive to a mass of abnormal cells upon interaction with the targeted site.

This application discloses a three-dimensional dose reconstruction method and related equipment based on in-beam positron emission tomography (PET) data. The method includes: acquiring list-pattern data during proton therapy beam exit; performing conformation processing on the list-pattern data and reconstructing a three-dimensional activity distribution map; performing multi-nucleus dynamic deconvolution processing on the activity time series corresponding to the three-dimensional activity distribution map according to the physical half-life of the target nuclide and preset biological elution parameters to obtain the initial activity distribution corresponding to the target nuclide; mapping the initial activity distribution to a three-dimensional relative dose distribution using a preset dose mapping algorithm; converting the three-dimensional relative dose distribution into a three-dimensional absolute dose distribution according to a pre-established water phantom calibration curve; and generating a cumulative dose distribution report based on the three-dimensional absolute dose distribution. The embodiments of this application can reconstruct the three-dimensional absolute dose distribution with high accuracy and support inter-session dose accumulation analysis. This application can be widely applied in the field of dose reconstruction technology.

The invention discloses an in-vitro tissue thermal dose threshold determination method and system based on a thermochromic film, and belongs to the technical field of biomedicine ultrasonic dosimetry. The method comprises the following steps: preparing a thermochromic film with multiple color-changing temperature points, and calibrating a quantitative relationship between the hue and the temperature of the thermochromic film; constructing a sample formed by overlapping an in-vitro tissue, the thin film and a transparent phantom, and placing the sample in a focal region of a high-intensity focused ultrasound system; synchronously carrying out ultrasonic irradiation and film color-changing video acquisition; hue distribution of video frames is converted into temperature distribution through image processing, dynamic accumulation is carried out based on a thermal dose model, and a two-dimensional thermal dose distribution field is reconstructed; and finally, registering the thermal damage area after tissue irradiation with a thermal dose field, and extracting a thermal dose value on the outer side of the damage boundary to calculate a threshold value. The system comprises corresponding ultrasonic generation, sample bearing, image acquisition and control processing units. According to the invention, non-contact, real-time and two-dimensional visual measurement of the heat dose is realized, the system cost is low, and the heat dose threshold can be determined more objectively and accurately.

The invention relates to a coaxial and non-coplanar magnetic resonance guided head gamma knife radiotherapy system and a guiding method thereof. The system comprises a magnetic resonance imaging unit, a gamma knife irradiation unit, a treatment bed unit, a coordinate registration unit, a body surface optical tracking unit and a control system. The gamma knife irradiation unit is rigidly connected to the end face of the magnetic resonance imaging unit through a positioning interface, a positioning bed board is arranged on the treatment bed unit, a space reference mark is arranged on the positioning bed board, and the coordinate registration unit is connected between the magnetic resonance imaging unit and the treatment bed unit. The body surface optical tracking unit is mounted at the tail end of a positioning bed plate of the treatment bed unit; the control system is connected with the treatment bed unit, the gamma knife irradiation unit and the body surface optical tracking unit. Clear imaging of cranial soft tissue in a high-field-intensity environment can be realized, damage of external components to magnetic field uniformity and interference of an electron reflux effect caused by a high-intensity magnetic field to dose distribution are reduced, and radiotherapy precision is improved.

Disclosed is a computer-implemented method for determining a treatment plan for a radiotherapy treatment including a dose distribution, the method comprising the steps of (a) determining a plurality of clinical goals, the plurality of clinical goals associated with a dose distribution, (b) determining, based at least in part on a user input, a priority for each of the clinical goals, (c) automatically determining a subset and order of scripts among a plurality of scripts, based on the plurality of clinical goals and their respective priority, each script configured to, when executed, adapt one or more optimization objectives and / or adapt weightings for optimization and / or provide and / or adapt an optimization structure, (d) generating a dose distribution, wherein the generating of the dose distribution comprises executing the subset of scripts in the determined order, wherein executing the subset of scripts comprises, for each of the scripts, obtaining at least one of an optimization structure, optimization objectives, and weightings for optimization,