41 results about "Planned Dose" patented technology

The present invention provides a novel method of contoured-anatomy dose repositioning (CADR) as a means to automatically reposition a patient to better recover the planned dose distribution without reoptimize the treatment plan. Specifically, CADR utilizes planning CT images, the planned dose distribution, and on-line images for repositioning dose distribution on a given day. Contours are also placed upon the images using manual, automatic, template-based, or other techniques. CADR then optimizes the rigid-body repositioning of the patient so that the daily dose distribution closely matches the planned dose distribution. The present invention also provides a method of multiple-margin optimization with daily selection (MMODS) to improve radiation delivery without reoptimization. During the initial optimization procedure, plans are optimized for several margins of various contours (e.g., tight, medium, loose, etc.), or with different objectives (e.g., aggressive treatment, sensitive structure sparing, etc.). Similarly, if multiple patient image sets are available, plans can be optimized for the different anatomical layouts, either using current information, or accumulated information regarding the superposition of organ locations in the combination of images. A user can then choose in real time from a variety of optimized plans, generally with different margins, during the treatment process, and thereby compensate for a recognized change in size or position of the tumor or neighboring tissue.

An accurate method for inversely verifying a therapeutic radiation dose delivered to a patient via an x-ray delivery system without involving any computational iteration was developed. The usage of it includes detecting the transmitted radiation dose image after passage through the patient, imaging the patient during treatment to anatomically record information of the patient, followed by inversely verifying through use of both the detected radiation image and the imaging data, the actual radiation dose delivered to the patient, and comparing the level of the dose delivered to a previously planned dose to determine whether the planned dose was delivered, or whether an overdose or underdose occurred.

In external beam radiation therapy, a planning image (scan) of the patient is obtained prior to treatment as a basis for constructing a radiation delivery plan. However, since the planning scan is obtained prior to treatment (potentially days or weeks prior), it does not necessarily represent the state of the patient's anatomy as it presents at the time of treatment beam delivery. The potential mismatch between the patient's anatomy in the planning scan and anatomy at the time of treatment can result in dose discrepancies between the planned dose and the actual delivered dose. The methods herein describe the use of online images taken immediately before or during treatment delivery in order to predict, assess, and adapt to such discrepancies.

The invention discloses a dose-guided precise radiotherapy real-time verification system, which mainly comprises a patient data management module, a three-dimensional dose reconstruction module and adose evaluation module which are connected successively; the patient data management module is used for obtaining a radiotherapy patient data set from a radiotherapy information management system andproviding data input for the functional module of the system; the three-dimensional dose reconstruction module implements the scattering correction of a patient cone beam CT image, field transmissionimage acquisition, real-time dose calibration, and three-dimensional dose reconstruction functions; the dose evaluation module provides a dose assessment method and a result visualization function, and a user selects a two-dimensional dose assessment or a three-dimensional dose assessment as needed to provide decision-making data for a radiation therapist to perform subsequent fractional treatmentand plan correction. The dose-guided precise radiotherapy real-time verification system uses modular design, and uses a dose-guided radiotherapy plan to perform precise and real-time quality controltreatment, thereby achieving a precise coincidence of the therapeutic dose and the planned dose.

The invention discloses a dose-guided self-adaptive radiotherapy planning re-optimization system and method. The system includes a guide module, a data processing module, a plan re-optimization judgment module and a plan re-optimization module. The guide module is used for guiding the reference image, anatomical structure, planning and dose information of a research object, and an image for guiding precise positioning during current fractional treatment; the data processing module is used for calculating the anatomical structure of the current image and the anatomical structure of a referenceimage; the plan re-optimization judgment module is used for judging whether to enter the plan re-optimization module or not according to the anatomical structure change, the actual dose received by patients is compared with the planned dose if the anatomical structure change is within the threshold, re-optimization is needed if there are great difference between the actual dose and the planned dose, otherwise, an original reference plan is used as the current treatment plan. The plan re-optimization not only considers the difference between the current anatomical structure and the original anatomical structure, but also uses the fast conjugate gradient algorithm to automatically optimize the plan according to the actual dose received by the research object.

A method for generating a radiotherapy treatment plan for a patient is provided. The treatment plan is optimized by using an optimization objective which is at least partly based on an initially planned dose to the patient.

A method of electronic portal imaging (EPID) for radiation dosimetric measurement and quality assurance (QA) in radiation therapy is provided that includes imaging a calibration photon beam and a treatment beam using an EPID imager disposed between a plastic water build-up phantom and a plastic water back-scatter phantom that is thicker than the plastic water build-up phantom, correcting the EPID images using an off-axis correction map that takes into account a horn-shape of a photon fluence profile, deconvolving the corrected EPID images using a Monte Carlo simulated EPID response kernel, the deconvolved corrected EPID images provide a primary photon fluence map, reconstructing a relative dose map using the primary photon fluence map convolving with a Monte Carlo simulated pencil-beam dose distribution kernel, and generating an absolute dose map using cross calibration to a 10x10 cm2 square field that is compared with a planned dose distribution for QA analysis.

The invention relates to an interpolation algorithm for intensity-modulated radiation therapy plan dose data based on gradient features, belonging to the technical field of intensity-modulated radiation therapies. The interpolation algorithm comprises the following steps: obtaining various gradient edge points and non-gradient edge points on an intensity-modulated radiation therapy plan dose data plane by adopting an improved traditional Canny algorithm according to gradient features of the intensity-modulated radiation therapy plan dose data plane; obtaining a coefficient of a bicubic interpolation kernel corresponding to each point on the intensity-modulated radiation therapy plan dose data plane according to the acutance of a gradient profile corresponding to the obtained gradient edge points and the deviation coefficient corresponding to the non-gradient edge points; and performing bicubic interpolation of each point to be interpolated by using the coefficient of the bicubic interpolation kernel so as to obtain the intensity-modulated radiation therapy plan dose data of each point to be interpolated. The interpolation algorithm disclosed by the invention overcomes the smoothing effect of the traditional bilinear interpolation while the error is reduced; and the original gradient information is reserved.

A method of minimizing radiation toxicity in image guided radiotherapy (IGRT) is provided that includes using a probabilistic prediction algorithm that is operated on a suitably programmed computer and includes multimodality inputs and provides real-time geometric and topological target estimates to compensate for system latency, using an online adaptive imaging system that provides radiographic images of the target when the geometric and topological target estimates are in a region of predefined uncertainty, and using an image dose control algorithm, operating on a suitably programmed computer, that includes parameters for controlling dose per image, where instances for image acquisition are optimized according to a planned dose pattern and delivery result.

The invention discloses a real-time monitoring method for a particle radiotherapy beam. The monitoring method comprises the following steps: the irradiation position, size, shape, uniformity and half-height width of a proton beam can be monitored in real time according to two-dimensional distribution of Cherenkov light intensity; actual output energy of the proton beam can be determined on the basis of the quantitative relationship between Cherenkov light intensity and the energy of the proton beam; the dose deviation value can be calculated according to the real-time deviation information ofbeam output. The novel method is simple, practical, stable and reliable and capable of comprehensively monitoring beam information (including energy, irradiation position, size, uniformity and half-height width) in the proton radiotherapy process in real time, and accurate supply of the planned dose can be effectively ensured.

The invention relates to a system and a method for evaluating a treatment plan for an external radiation therapy treatment, the treatment plan comprising parameters for controlling an external radiation therapy apparatus during the treatment. The system comprises a database storing historic treatment plans and storing for each historic treatment plan a quality parameter indicative of whether a deviation between a planned dose distribution and a measured dose distribution resulting from an execution of the treatment plan is within an acceptable limit. An evaluation unit determines a threshold value for each of a plurality of treatment plan metrics based on the historic treatment plans and the associated quality parameters. Further, the evaluation unit calculates a value of each of the metrics for the treatment plan and compares the value of each of the metrics with the threshold value determined for the respective metric.

It is an object of the invention to improve treatment planning. This object is achieved by a dose planning system comprising a biopsy map creation module configured for receiving biopsy information for an organ of interest regarding biopsy locations and tissue characteristics of tissue found at the biopsy locations, wherein the biopsy map creation module is further configured for creating a spatially annotated biopsy map for the organ, by linking the spatial information on the biopsy locations to the tissue characteristics of tissue found at the corresponding biopsy locations. The dose planning system further comprises a probability map calculation module configured for creating a tumour probability map by calculating a tumour probability for locations in the organ from which no biopsy was taken by using the tumour and/or tissue characteristics from the biopsy locations and a dose planning module configured for creating a dose plan based on the tumour probability map, wherein planning constraints are such that on average a higher tumour probability results in a higher planned dose and a lower tumour probability results in a lower planned dose.

Novel normoxic N-(Hydroxymethyl) acrylamide (NHMAGAT) polymer gel dosimeters for MRI scanning are introduced for radiotherapy planning system. The composition of the NHMAGAT polymer gel and method of making the NHMAGAT polymer gel dosimeter are disclosed. The dosimeters are irradiated with Varian Rapid Arc linear systems at different absorbed doses. The results show that the percent depth dose and 2D plan dose distribution of NHMAGAT polymer gel dosimeters are in a good agreement with the ionization chamber measurements and CT planned dose distribution, respectively.

A method includes generating a nominal dose distribution based on an image and clinical goals. The method further includes generating a setup error dose distribution based on range and setup uncertainties. The method further includes generating a dose distribution for a parameter of an internal organ. The method further includes optimizing a planned dose distribution of an intensity modulated proton therapy plan by minimizing a total objective value including the nominal dose distribution, the setup error dose distribution dose distribution, and the dose distribution for the internal organ. The method further includes generating a final dose distribution for the intensity modulated proton therapy plan based on beam parameters of the optimized planned dose distribution. The method further includes controlling a proton therapy apparatus configured to deliver proton therapy based on the intensity modulated proton therapy plan with the optimized planned dose distribution.