508 results about "Dose distribution" patented technology

A mixed irradiation evaluation support system for supporting judgment and determination of allocation of contribution in mixed irradiation using proton beams and X-rays. According to a composition ratio designated by a composition ratio scroll bar 107, a dose distribution by a proton beam and a dose distribution by an X-ray are composed, and the result of the composition is displayed three-dimensionally in a three-dimensional display part 104. Further, when a cross section is designated in the three-dimensional display part 104, an isodose map 115 in the designated cross section is displayed in a cross section window 114.

The present invention relates to a device and method for monitoring and verification of the quality of a radiation treatment beam in conformal radiation therapy, and in particular for IMPT (Intensity Modulated Particle Therapy) applications. The device comprises a 2D electronic detector measuring 2D responses to the delivered treatment beam. These 2D responses are compared with predicted 2D responses and differences in responses are signalled. Based on the measured 2D responses the effectively delivered 3D dose distribution in the target can be reconstructed.

The invention relates to a method for accurately fixing the radiation output amount in radiotheraphy, which comprises that setting coordinate on patient, to obtain the information of ill part; setting the radiation coordinate at the injection direction of accelerator, building the projection between the human coordinate and the injection coordination; calculating out the agent distribution generated in the injection grid matrix of injection coordinate; building the formula of output MU; building the body model, processing radiation analogue calculation on the body model, radiating with machine, detecting the radiation amount via the detector in the body model, checking the error between the analogue calculated agent and the detected agent, to reach the demand. The invention builds accurate algorism (A) to be used in variable radiation systems with high accuracy.

The invention is a novel adaptive CT-compatible brachytherapy applicator with remotely-controlled radial and longitudinal motion radioactive source lumen shields that can be manipulated by the radiation oncologist to optimize the dose distribution to the target and normal tissue structures for brachytherapy procedures.

A detector having a collimator in a position at a specific angle with respect to a therapeutic X-ray beam is mounted to selectively detect only scattering radiation in the direction. To three-dimensionally obtain a distribution of places where scattering occurs in a patient body, a detector is rotated during irradiation and scattering radiation is measured from all of directions. After that, a reconstructing process is performed, and a distribution of occurrence of scattering radiation in the subject is three-dimensionally imaged. Since angles and amounts of X-rays scattered by Compton scattering are known theoretically, if scattering radiation at a certain angle can be detected, the number of scattering radiation at other angles can be also estimated. On the basis of the theory, images of distribution of scattering radiation sources are converted to images of distribution of absorption of radiation.

A system and methods are provided for generating intensity modulated proton therapy plans robust to various kinds of delivery uncertainties with the capability for treatment planners to control the balance between plan quality and robustness. The system obtains a representation of a subject and a proton beam configuration that describes a number of beamlets and their respective arrangement. The system computes an objective function, in the treatment planning system, first part of which is about dose deviations from the prescribed dose in the target volumes, second part of which is about dose deviations from the dose constraint in the non-target volumes, and computing dose volume constraints for targets using a probability to control the dose distribution in the target volumes to be between a lower threshold and an upper threshold. Based on this information, the system obtains a robust chance-constrained treatment planning model with a user-adjustable tolerance level.

The invention relates to an on-line dose modulation method of an X-ray CT (Computed Tomography) machine, which comprises the following steps: scanning plain film data, extracting Z-direction attenuation information of a human body, and calculating the attenuation area of the human body in each cut film along the Z direction; according to the attenuation area, calculating the average X-ray dose in each cut film to form a dose distribution curve along the Z direction, and supplying to a user as an initial recommended value, so that the user can adjust the dose distribution in the Z direction as required; scanning a patient, and simultaneously carrying out on-line estimation on the attenuation value of the rotation direction of the patient to obtain an attenuation estimated value; combining the dose distribution in the Z direction with the attenuation estimated value of the human body in the rotation direction to calculate a bulb tube mA value; transmitting the mA value to a high-pressure system, and carrying out high-frequency dose adjustment; and finishing the on-line dose modulation process if the scanning is completed. The invention reduces the overexposure and underexposure possibly caused by assuming sine laws. Besides, the invention does not assume that what passes through the central passage is the maximum attenuation, so that the dose modulation is better matched with the shape of the actual object.

The present invention relates to a method to measure dose distribution in a patient-shaped phantom with high accuracy. The invention consists of a method of measuring dose distribution in a phantom for radiation therapy treatment verification, a detector configuration in such a phantom, detector improvement and measurement methodology to enable application of correction factors in an accurate way.

Brachytherapy is carried out with a needle to inject a radioactive seed into a patient's body. A space-fixed detector detects radiation from radiation emitters to determine the position of a deposited seed from the needle with reference to a space-fixed coordinate system. Markers may be affixed to the patient's body such that a body-fixed coordinate system can be determined in real time by an imaging device. Alternatively, earlier obtained patient's anatomical data may be referenced. After positions of earlier injected seeds are thus ascertained in real time in the body-fixed coordinate system, the stored anatomical data may be updated and a radiation dose distribution can be calculated from the determined seed positions. The calculated radiation dose distribution can be displayed and compared with a planned distribution.

Compact particle selection and collimation devices are disclosed for delivering beams of protons with desired energy spectra. These devices are useful with laser-accelerated proton therapy systems, in which the initial protons have broad energy and angular distributions. Superconducting magnet systems produce a desired magnetic field configuration to spread the protons with different energies and emitting angles for particle selection. The simulation of proton transport in the presence of the magnetic field shows that the selected protons are successfully refocused on the beam axis after passing through the magnetic field with the optimal magnet system. Dose distributions are also provided using Monte Carlo simulations of the laser-accelerated proton beams for radiation therapy applications.

An ion implantation method includes scanning reciprocatingly an ion beam in an X direction by an electric field or magnetic field and mechanically driving reciprocatingly a substrate in a Y direction orthogonal to the X direction to implant ions over the entire surface of the substrate. A dose distribution that is non-uniform within the plane of the substrate is formed within the plane of the substrate by changing at least one of a scanning speed of the ion beam and a driving speed of the substrate within an area where the ion beam is incident on the substrate.

The invention discloses a method of dose reversal of the target of a patient in radiotherapy, the method makes use of a light source and a flat panel detector to carry out the rotary scanning around the target of the patient, so as to obtain the data of the target image of the patient and the dose data which penetrates the target of the patient; the invention applies a virtual PI line reconstruction algorithm to carry out the reconstruction and processing, and the treatment is carried out by adjusting the position of the patient and the input dose distribution data according to the processing results. As the invention adopts a true three-dimensional image reconstruction algorithm which is based on the flat panel detector, the spatial resolution of the true three-dimensional image is isotropic, the invention does not need interpolation, and can directly realize the processing of the image on the three-dimensional space, thus greatly improving the imaging precision and solving the problem that the imaging is not precise due to the interpolation error during the integration process into a quasi three-dimensional image of the existing radiotherapy, which can further affect the accurate implementation of the treatment plan of focus.

In a particle therapy treatment planning system for creating treatment plan data, the movement of a target (patient's affected area) is extracted from plural tomography images of the target, and the direction of scanning is determined by projecting the extracted movement on a scanning plane scanned by scanning magnets. Irradiation positions are arranged on straight lines parallel with the scanning direction making it possible to calculate a scanning path for causing scanning to be made mainly along the direction of movement of the target. The treatment planning system can thereby realize dose distribution with improved uniformity.

The invention relates generally to treatment of solid cancers. More particularly, a method and apparatus for efficient radiation dose delivery to a tumor is described. Preferably, radiation is delivered through an entry point into the tumor and Bragg peak energy is targeted to a distal or far side of the tumor from an ingress point. Delivering Bragg peak energy to the distal side of the tumor from the ingress point is repeated from multiple rotational directions. Beam intensity is proportional to radiation dose delivery efficiency. The multi-field irradiation process with energy levels targeting the far side of the tumor from each irradiation direction provides even and efficient charged particle radiation dose delivery to the tumor. Preferably, the charged particle therapy is timed to patient respiration via control of charged particle beam injection, acceleration, extraction, and/or targeting methods and apparatus.