Patent application number | Description | Published |
20090159804 | Positron 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 |
20100032574 | RADIATION 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 |
20100046818 | IMAGE 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 |
20100128956 | PET 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 |
20110001049 | METHOD 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 |
20110024637 | OPEN-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 |
20110024638 | PET 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 |
20110031407 | OPEN-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 |
20110084211 | DETECTOR-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 |
20110092814 | COMBINED 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 |
20110101229 | DOI 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 |
20120150017 | OPEN PET/MRI HYBRID MACHINE - A PET/MRI hybrid machine that combines a PET device with an MRI device, includes: an open PET device that has a PET field of view at least part of which is an open space accessible from outside; and an open MRI device that has an MRI field of view at least part of which is an open space accessible from outside, and the open space of the PET field of view and the open space of the MRI field of view are allowed to overlap each other at least in part. This makes it possible to simultaneously measure and image the same open space accessible from outside by the PET device and the MRI device, thereby acquiring functional information and morphological information at the same time. | 06-14-2012 |
20120150018 | SHIELD TYPE RADIATION THERAPY AND IMAGING HYBRID DEVICE - A shielding structure against nuclear fragments (referred to as a shield) is operated according to ON and OFF of beam irradiation so as to reduce incidence of nuclear fragments on detectors during beam irradiation. This enables measurement of annihilation radiations and three-dimensional imaging of the irradiation field immediately after irradiation or even during irradiation. | 06-14-2012 |
20120161014 | MULTI-PURPOSE PET DEVICE - In an open PET device including a plurality of detector rings that are arranged apart in the direction of the body axis of a subject and having a physical open field of view area, at least one of the detector rings or another imaging device arranged in parallel is configured to be movable by simple device moving means in order to change the configuration of the PET device. This improves the versatility of the open PET device for easier introduction to facilities. | 06-28-2012 |
20120165651 | DETECTOR ROTATION TYPE RADIATION THERAPY AND IMAGING HYBRID DEVICE - An imaging device, or a PET device, opposed gamma camera type PET device, or open PET device in particular, that is combined with a radiation therapy device, in which detectors are rotated to reduce incidence of nuclear fragments on the detectors. For example, in an opposed gamma camera type PET device, beam irradiation and detector rotation can be synchronized to prevent the detectors from interfering with the treatment beam and reduce the incidence of nuclear fragments on the detectors. This makes it possible to reduce the incidence of nuclear fragments on the detectors without interfering with a treatment beam, thereby enabling measurement of annihilation radiations and three-dimensional imaging of the irradiation field immediately after irradiation or during irradiation. | 06-28-2012 |
20130056638 | Three-dimensional radiation position detector and method of identifying sensed positions therein - A three-dimensional position-sensitive radiation detector is provided which has a three-dimensional array of photodetectors disposed on the surface of a scintillator block and which is capable of three-dimensionally identifying the position of light emission at which radiation has been detected within the detector. The three-dimensional position-sensitive radiation detector includes: a scintillator block including a central portion which restricts the direction of diffusion of light so as to direct the light in three axial directions and which has an optically discontinuous region, and an outer portion which is disposed on the outside of the central portion and which does not restrict the direction of diffusion of light; and photodetectors disposed on at least two outer circumferential surfaces of the scintillator block. The detector identifies three-dimensionally the position of light emission, thereby preventing deterioration in position discrimination performance even when inner scintillator elements are smaller than the photodetectors. | 03-07-2013 |