Patent•
Apparatus for performing positron emission computed tomography
28 Mar 1980-
TL;DR: In this article, an apparatus for effecting positron emission computed tomography comprises rows of a plurality of arrays of detectors arranged rotatably around a center of rotation in such way that at least one of the detectors in each array is desposed at an irregular position relative to the rest of detectors in the array, and that, for each revolution of the row through an angle of 360°/n (wherein: n represents an odd number of 3 or larger), each array of detectors will assume exactly the position occupied by its adjacent array till the revolution takes place.
Abstract: of the disclosure An apparatus for effecting positron emission computed tomography comprises rows of a plurality of arrays of detectors arranged rotatably around a center of rotation in such way that at least one of the detectors in each array is desposed at an irregular position relative to the rest of detectors in the array, and that, for each revolution of the row through an angle of 360°/n (wherein: n represents an odd number of 3 or larger), each array of detectors will assume exactly the position occupied by its adjacent array till the revolution takes place.
Citations
More filters
Patent•
02 Jun 1983
TL;DR: In this paper, the selected internal skeletal structure is measured by subjecting the body to radiant energy to produce radiant energy responses that are detected to obtain representations delineating the skeletal structure.
Abstract: Non-invasive method of forming prostheses of skeletal structures internal to a body for use in reconstructive surgery. The selected internal skeletal structure is measured by subjecting the body to radiant energy to produce radiant energy responses that are detected to obtain representations delineating the skeletal structure. Three dimensional coordinate data defining the skeletal structure is generated from the obtained representations. The coordinate data is employed to control a sculpting tool to form the prosthesis.
315 citations
Patent•
15 Sep 1987TL;DR: In this article, a ring of pillar-shaped scintillator elements and position detecting photodetectors coupled to the end surfaces of each element was used to detect a positron distribution over the entire visual field with high resolution.
Abstract: A scintillation detector for three-dimensionally measuring the absorption position of the gamma-rays entering the detector and a positron computed tomography apparatus employing as a gamma-rays detector plural scintillation detectors arranged in the form of a ring are provided which can prevent the degradation of the spatial resolution in the peripheral region of the visual field and uniformly detect a positron distribution over the entire visual field with high resolution. The scintillation detector comprises a bundle of pillar-shaped scintillator elements and position detecting photodetectors coupled to the end surfaces of each scintillator element, and the apparatus comprises a plurality of scintillation detectors formed in a ring, each of which includes a bundle of scintillator elements, and plural position detecting photodetectors each of which is connected to both ends of the scintillator bundle.
47 citations
Patent•
20 Jun 1989TL;DR: In this paper, a ring array of scintillation cyrstal/PMT gamma ray detectors are employed in a PET image volume to reduce the complexity and expense of associated electronic signal processing channels.
Abstract: A greatly reduced number of scintillation cyrstal/PMT gamma ray detectors are employed in a ring array about a PET image volume. Because of the relatively small number of such detectors, the complexity and expense of associated electronic signal processing channels is greatly reduced (even if each such channel is provided with sophisticated time of flight capabilities). Similarly, because relatively fewer crystals are employed, it becomes possible to use much larger and faster response time scintillation crystals so as to greatly increase gamma ray detection efficiency and scatter rejection while also permitting the electronic circuits to better reject random events and to provide effective time of flight image data filtering. By providing successively offset collimation apertures for each successive detector of the ring array and by rotating the array 360 degrees through a large number of successive view angle positions, it is nevertheless possible to acquire extremely high resolution image data with a greatly reduced system cost. A multiple aperture embodiment provides improved sensitivity by using associated light collimators and photodiodes in conjunction with slow coincidence steering circuits.
36 citations
Patent•
23 May 2001TL;DR: A PET device for providing an excellent quantitative feature by a proper correction of a scattered radiation effect while enhancing a resolution in a restructured image and keeping a good photon pair detection sensitivity is presented in this article.
Abstract: A PET device for providing an excellent quantitative feature by a proper correction of a scattered radiation effect while enhancing a resolution in a restructured image and keeping a good photon pair detection sensitivity. A judging unit (52) judges whether or not a line connecting mutually respective light receiving surfaces (15b) of a pair of photon detecting elements (15a) that has detected photon pair simultaneously crosses any one of slice collimators (21n). Coincidence information for which it is judged that the line crosses none of the slice collimators (21n) is stored in a first coincidence information storing unit (53), and a signal sinogram is generated. Coincidence information for which it is judged that the line crosses any one of the slice collimators (21n) is stored in a second coincidence information storing unit (54), and a scattered sinogram is generated. An image restructuring unit (60) corrects the effect of a scattered component in a signal sinogram based on a scattered sinogram, and an image is restructured based on this corrected signal sinogram.
31 citations
Patent•
05 Jul 1985TL;DR: In this paper, an organic compound is brought into contact with the fluoride ions in an apparatus to produce a reaction, and the reaction takes place at a temperature of between 100° C. and 150° C in the presence of a basic alkali salt which is contained in a acetamide melt.
Abstract: Organic compounds labeled with no-carrier-added fluorine 18 are processed yield a compound having a formula in the form of 18 F-R through a nucleophilic substitution reaction. The process has a series of steps. The first step of the process relates to providing an organic compound having a formula of X-R. X is the nucleophilic leaving group in the substitution action, and R is a preferred substituted hydrocarbon structure being selected from aliphatic, alicyclic, heterocyclic aliphatic, carbocyclic and heterocyclic aromatic structures. The X-R compounds with acid hydrogen are excluded. The next step is to bring the organic compound X-R into contact with fluoride ions which are present in a solvent. These fluoride ions are essentially carrier free 18 F ions. The organic compound is brought into contact with the fluoride ions in an apparatus to produce a reaction. The reacting mixture comes into contact during reaction only with surfaces in the apparatus which are made of metals as copper, stainless steel, platinum and Inconel and preferably of glassy carbon. In one embodiment, the reaction takes place at a temperature of between 100° C. and 150° C. in the presence of a basic alkali salt which is contained in a acetamide melt. The reaction may alternately take place in a preferred embodiment, in solution, in a moderately polar, aprotic solvent in the presence of a macrocyclic polyether and an alkali salt at a temperature in the range of 50° C. to 150° C.
21 citations
References
More filters
Patent•
18 Feb 1977
TL;DR: In this paper, a nuclear medicine imaging device is disclosed which provides tomographic sectional images of the human body subsequent to the administration of radio pharmaceuticals labelled with positron-emitting radionuclides.
Abstract: A nuclear medicine imaging device is disclosed which provides tomographic sectional images of the human body subsequent to the administration of radio pharmaceuticals labelled with positron-emitting radionuclides. Signals representative of the distribution of the radionuclide within the patient are generated and are used in computerized tomography to reconstruct the region under examination. Elongated scintillation detectors are utilized to span a plurality of tomographic sections and positioning circuitry is utilized with the detectors for said tomographic sections. As an alternative embodiment, said detectors are arrayed coplanarly around the subject and generate suitable information for said computerized emission tomographic reconstruction.
37 citations
Patent•
10 Jun 1975
TL;DR: In this article, a transverse section radionuclide scanning system for high-sensitivity quantification of brain radioactivity in cross-section picture format is presented, in order to permit accurate assessment of regional brain function localized in three-dimensions.
Abstract: This invention provides a transverse section radionuclide scanning system for high-sensitivity quantification of brain radioactivity in cross-section picture format in order to permit accurate assessment of regional brain function localized in three-dimensions. High sensitivity crucially depends on overcoming the heretofore known raster type scanning, which requires back and forth detector movement involving dead-time or partial enclosure of the scan field. Accordingly, this invention provides a detector array having no back and forth movement by interlaced detectors that enclose the scan field and rotate as an integral unit around one axis of rotation in a slip ring that continuously transmits the detector data by means of laser emitting diodes, with the advantages that increased amounts of data can be continuously collected, processed and displayed with increased sensitivity according to a suitable computer program.
35 citations
Patent•
27 Aug 1979TL;DR: In this article, a positron annihilation imaging device has two circular arrays of detectors disposed in spaced apart parallel planes, where axially movable annular collimator rings are generally disposed in a pair of opposite planes outside the associated planes of the collimators to each collimmer being movable toward the opposite collimmer.
Abstract: A positron annihilation imaging device having two circular arrays of detectors disposed in spaced apart parallel planes wherein axially movable annular collimator rings are generally disposed in a pair of opposite planes outside the associated planes of the collimators to each collimator being movable toward the opposite collimator and a central collimator of annular configuration generally disposed between the two rows of detectors but being split into two rings which may be separated, the outer and inner collimators serving to enhance data readout and imaging.
12 citations
Patent•
30 Dec 1977TL;DR: In this paper, an array of highly focused collimators surrounding a scan field are used for a scan-based collimator-based object detection system, where the object is assumed to be static.
Abstract: Scanning apparatus is provided for an array of highly focused collimators surrounding a scan field.
11 citations