Patent classifications
G01T1/023
Radiation dose measuring method
Provided are a method for measuring dose distribution in a mixed radiation field of neutrons and gamma rays, and a method for measuring beam uniformity of a mixed radiation field of neutrons and gamma rays. The planar dose measuring method includes: a step of obtaining a total dose of neutrons and gamma rays by measuring with a dosimeter; and a step of analyzing a neutron dose. The method may effectively measure the doses of neutrons and gamma rays, may be applied to beam measurement and treatment plan validation, and thus improve the quality of treatment.
PSD SENSORS FOR HEAD AND NECK
A radio-opaque plastic scintillator detector (PSD) for use in various head and neck radiation applications is described. Bite plates, nose cones and ear cones are provided for use therewith, each having hollow tubes into which PSD cables can be inserted for real time measurement of radiation during treatment.
X-RAY ENERGY DISTRIBUTION MEASUREMENT APPARATUS AND X-RAY THERAPY APPARATUS
The radiation detection device includes a plurality of radiation detectors arranged in a row and is inserted into the body of patient subjected to the X-ray therapy. An X-ray detection signal (photon) is output from each of the radiation detectors that detects the X-ray applied to the patient. The dose rate measurement device separately connected to each of the radiation detectors obtains the dos rate at the position of each radiation detector based on the signals. The irradiation direction determination device determines whether the row of radiation detectors matches the irradiation direction of the X-ray using the dos rate obtained by each of the dose rate measurement devices. When the row of radiation detectors matches the irradiation direction, the energy distribution analysis device obtains an energy distribution using the dose rate at the positions of the radiation detectors by applying, for example, an inverse problem analysis called an unfolding method.
Detector, three-dimensional direct positron imaging unit, and method to estimate the differential of the radiation dose provided to cancer cells and healthy tissues during hadrotherapy
Disclosed is a detector for a positron imaging unit, comprises a hollow body with an inner cylindrical wall and an outer wall spaced apart from the inner cylindrical wall. The hollow body includes a scintillating material, suitable to emit photons once hit by a 511 keV -ray, and one or more pairs of photo-detecting units (e.g. comprising PMTs or SiPM) for detecting photons emitted by the scintillating material; each photo-detecting unit of a pair being placed at opposite ends of the inner cylindrical wall along a radial direction. The scintillating material has scintillation decay time lower than 10 ns, an atomic number greater than 10, and a high scintillation yield greater than 8,000 photons/MeV, and comprises a mixture of xenon and argon. An imaging unit including the detector and a method to estimate the differential of the dose of radiation provided in a subject to cancer cells and to surrounding tissues in the course of hadrotherapy is also disclosed.
DOSIMETER APPARATUS AND METHODS
A dosimeter for characterising a spatial distribution of a radiation dose in a sensing region, the dosimeter comprising; a plurality of scintillation fibres extending substantially parallel to a first direction in the sensing region and arranged in a two-dimensional array in a plane perpendicular to the first direction, wherein the radiation absorption properties of the plurality of scintillation fibres are configured to approximate the radiation absorption properties of human body tissue; and a photodetector comprising a plurality of photodetector regions coupled to respective ones of the plurality of scintillation fibres so as to generate signals for respective ones of the photodetector regions in response to radiation interaction events in corresponding ones of the scintillation fibres; further comprising a controller arranged to receive the signals from the photodetector regions and to determine a spatial distribution of a radiation dose in the sensing region.
REAL TIME ENVIRONMENTAL RADIATION MONITORING
A wearable dosimeter providing real-time radiation measurements based on sensitive, high gain scintillator crystals and a multipixel photon counter.
RADIATION DOSE MEASURING METHOD
Provided are a method for measuring dose distribution in a mixed radiation field of neutrons and gamma rays, and a method for measuring beam uniformity of a mixed radiation field of neutrons and gamma rays. The planar dose measuring method includes: a step of obtaining a total dose of neutrons and gamma rays by measuring with a dosimeter; and a step of analyzing a neutron dose. The method may effectively measure the doses of neutrons and gamma rays, may be applied to beam measurement and treatment plan validation, and thus improve the quality of treatment.
DOSIMETER AND RADIOTHERAPY SYSTEM
The dose measurement device includes: a radiation sensor constituted by a light emitting portion that is made of a polycrystalline scintillator and emits light of intensity dependent on an amount of incident radiation and a cover covering the light emitting portion; an optical fiber that is connected to the radiation sensor and transmits the photons emitted by the polycrystalline scintillator; a photoelectric converter for converting the photons transmitted by the optical fiber into electrical signals; a calculation device for measuring each of the electrical signals through the conversion by the photoelectric converter of each photon, calculating a count rate, and specifying a dose rate; and a display device for displaying measurement results calculated by the calculation device.
Radiation dose detector with embedded optical fibers
An embedded optical fiber radiation dose detector, includes: a first optical fiber probe, wherein a first end of the first optical fiber probe is connected to a first light intensity detector, and a second end of the first optical fiber probe is a detecting end, wherein a first fluorescent material is embedded in a terminal of the detecting end of the first optical fiber probe. Advantages are as follows: the optical fiber probes of the present invention have an embedded structure, wherein an optical fiber probe, whose core is hollow inside, is produced with a micro processing technology, and the fluorescent material is embedded therein, so as to significantly improve an efficiency of coupling radiation-generated fluorescent signals into the cores of the optical fibers, and significantly decreases a size of an optical fiber sensor.
Scintillator and radiation dosimeter using same
Provided are a scintillator with improved energy sensitivity dependence within the energy range of diagnostic X-rays, more specifically in the range of 40-150 kV, and a radiation dosimeter using same. Due to the scintillator comprising a photopolymer resin that contains a polymerizable monomer, a filler, and a photopolymerization initiator, energy sensitivity dependence within the range of 40-150 kV is improved. Furthermore, changes in relative sensitivity within this energy range can be reduced to 3% or less by containing an inorganic fluorescent substance such as Zn.sub.2SiO.sub.4.