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Hideo Murayama, Chiba-Shi JP

Hideo Murayama, Chiba-Shi JP

Patent application numberDescriptionPublished
20090159804Positron emission tomography scanner and radiation detector - A positron emission tomography (PET) scanner is provided which uses information on the time-of-flight difference (TOF) between annihilation radiations for image reconstruction. The scanner has detection time correction information (memory) corresponding to information on coordinates in a radiation detection element (e.g., scintillator crystal), in the depth and lateral directions, at which an interaction has occurred between an annihilation radiation and the crystal. Reference is made to the detection time correction information, thereby providing information on time-of-flight difference with improved accuracy. As such, an improved signal to noise ratio and spatial resolution are provided for image reconstruction using time-of-flight (TOF) difference.06-25-2009
20100032574RADIATION DETECTING METHOD UTILIZING ENERGY INFORMATION AND POSITIONAL INFORMATION AND EQUIPMENT THEREOF - Upon detection of radiation by using a (three-dimensional) detector capable of distinguishing a detection position in a depth direction and energy, an energy window for distinguishing between a signal and noise is changed depending on the detection position in the depth direction, thus making it possible to obtain scattering components inside the detector. Alternatively, a weight is given to a detection event depending on the detection position in the depth direction and energy information to obtain scattering components inside the detector. Thereby, scattering components inside the detector can be obtained to increase the sensitivity of the detector. In this case, different detecting elements can be used depending on the detection position in the depth direction.02-11-2010
20100046818IMAGE RECONSTRUCTION METHOD FOR TOMOGRAPHY SCANNER, FAILURE DIAGNOSIS METHOD, TOMOGRAPHY SCANNER AND MANAGEMENT PROGRAM FOR SYSTEM MATRIX - In a case where an error is included in measurement data corresponding to one or a plurality of detecting elements in a tomography scanner, a system matrix to be calculated or referenced on image reconstruction calculation is corrected in accordance with the error. Thus, even when an error such as a defect or a fault occurs in a detector, influence of the error is eliminated, thereby reducing an artifact generated in an image. At that time, positional information of the detecting elements including the error and information on the degree of the error are stored in a storage device and referenced inside image reconstruction software, thus making it possible to correct the system matrix in accordance with the error.02-25-2010
20100128956PET SCANNER AND IMAGE RECONSTRUCTION METHOD THEREOF - A plurality of detector rings in which detectors arranged densely or spatially in a ring shape or in a polygonal shape are arranged, with an open space kept in the body axis direction, coincidences are measured for some of or all of detector pairs connecting the detector rings apart from the open space to perform three-dimensional image reconstruction, thereby imaging the open space between the detector rings as a tomographic image. Therefore, the open space is secured, with the deteriorated quality of an image suppressed, thus making it possible to easily gain access to a patient under PET scanning from outside a gantry and also provide irradiation of particle beams for cancer treatment as well as X-ray CT scanning.05-27-2010
20110001049METHOD FOR DETECTING RADIATION, DEVICE THEREOF, AND POSITRON EMISSION TOMOGRAPHY SCANNER - A light receiver for detecting incident time is installed on the side of a radiation source of a scintillator (including a Cherenkov radiation emitter), and information (energy, incident time, an incident position, etc.) on radiation made incident into the scintillator is obtained by the output of the light receiver. It is, thereby, possible to identify an incident position and others of radiation into the scintillator at high accuracy.01-06-2011
20110024637OPEN-TYPE PET SCANNER - In an open-type PET scanner, detector rings arranged in a multilayered manner in an axial direction are at least partially opened and the thus opened part of the detector rings is at least partially included in a main focus region. Then, at least some of the detecting elements constituting the detector ring are disposed obliquely in the axial direction so that the main sensitivity direction thereof is turned closer to the main focus region, increasing the resolution in the main focus region. Thereby, it is possible to retain resolution in the body axis direction without using a high-resolution DOI detector and to reduce the price of the open-type PET scanner.02-03-2011
20110024638PET SCANNER AND METHOD FOR DECIDING ARRANGEMENT OF DETECTORS - A PET scanner in which detector rings are arrayed in a multilayered manner so as to oppose each other in the body axis direction is provided. In the PET scanner, a predetermined number of detector units, each of which is made up of a predetermined number of detector rings, are arrayed so as to give each other a clearance, and a first ring set in which the clearance is less than or equal to a mean value of widths of two detector units forming each clearance and a second ring set constituted with a predetermined number of detector units are arrayed apart so as to give a clearance which is less than or equal to a mean value of the width of the first ring set and that of the second ring set, thereby imaging a field-of-view including the clearance and continuing in the body axis direction to an entire length of the first ring set and that of the second ring set.02-03-2011
20110031407OPEN-TYPE PET SCANNER - In an open-type PET scanner including a plurality of detector rings having multiple rings arrayed in the body axis direction, radiation measurement is performed while at least one detector ring is relatively moved with respect to a subject in the body axis direction, thereby dispersing simultaneous radiation in an open region to suppress a local reduction in sensitivity. The detector rings are optimized in constitution, moving direction and/or moving speed, thus making it possible to reduce the variation of distribution of sensitivity and expand a clearance in the open region and a field-of-view in the body axis direction.02-10-2011
20110084211DETECTOR-SHIFT TYPE COMBINED RADIATION THERAPY/PET APPARATUS - In beam monitoring for detecting annihilation radiations produced by radiation irradiation in radiation therapy for cancer which is performed by irradiating the affected area by X-rays, gamma rays, or particle beams, a detector-shift type combined radiation therapy/PET apparatus is provided with an open PET device that includes a plurality of shiftable multi-ring detector rings; and a radiation irradiation device that is capable of irradiation with a radiation beam through between the detector rings. The apparatus changes the positions of the detector rings, performs irradiation with the radiation beam through between the detector rings, and then performs radiation measurement.04-14-2011
20110092814COMBINED RADIATION THERAPY/PET APPARATUS - A combined radiation therapy/PET apparatus includes: an open PET device having multi-ring detector rings that are opposed to each other in the direction of the body axis so as to leave a gap therebetween; and a radiation therapy apparatus for performing radiation therapy through the gap. When imaging the condition of an affected area and a treatment beam for monitoring in radiation therapy of irradiating the affected area with X-rays, gamma rays, or particle beams, the apparatus covers a region of interest in the irradiation field of the radiation therapy with the field-of-view of the open PET device, thereby making possible the positioning of the irradiation field and treatment monitoring using PET images.04-21-2011
20110101229DOI TYPE RADIATION DETECTOR - This aims to provide a DOI type radiation detector in which scintillation crystals arranged two-dimensionally on a light receiving surface to form rectangular section groups in extending directions of the light receiving surface of a light receiving element are stacked up to make a three-dimensional arrangement and responses of the crystals that have detected radiation are made possible to identify at response positions on the light receiving surface, so that a three-dimensional radiation detection position can be obtained. In the DOI type radiation detector, scintillation crystals are right triangle poles extending upwards from the light receiving surface and the response positions on the light receiving surface are characterized. With this structure, DOI identification of a plurality of layers can be carried out by simply performing an Anger calculation of a light receiving element signal.05-05-2011

Patent applications by Hideo Murayama, Chiba-Shi JP