Abstract: A CT scanner with scatter correction device and a method for scatter correction are provided. The method comprises positioning shields for shielding some of the CT detector elements from direct X ray radiation, while allowing scattered radiation to arrive at said shielded elements; measuring scatter signals from said shielded elements, indicative of scattered radiation intensity; and correcting for scatter by subtracting scatter intensity values estimated from said measured scatter signals from signals measured by unshielded detector elements.

Abstract: A dual energy CT scanner includes an X ray source generating an X-ray beam, a stacked detector array for detecting radiation from the X-ray beam, the stacked detector array including a first layer of detectors and a second layer of detectors, wherein a packing density of detectors in at least a portion of the first layer is different than a packing density of detectors in a corresponding portion of the second layer, a data acquisition unit for sampling data from the detectors in the first and second layer; and an image reconstruction unit for reconstructing an image from data acquired from at least one layer of the stacked detector array.

Abstract: A radiation detector (24) includes a two-dimensional array of upper scintillators (30?) which is disposed facing an x-ray source (14) to convert lower energy radiation events into visible light and transmit higher energy radiation. A two-dimensional array of lower scintillators (30B) is disposed adjacent the upper scintillators (30?) distally from the x-ray source (14) to convert the transmitted higher energy radiation into visible light. Upper and lower photodetectors (38?, 30B) are optically coupled to the respective upper and lower scintillators (30?,30B) at an inner side (60) of the scintillators (30?,30B). An optical element (100) is optically coupled with the upper scintillators (30?) to collect and channel the light from the upper scintillators (30?) into corresponding upper photodetectors (38?).

Abstract: A CT scanner for multiple energy CT scanning of a subject having an X-Ray source adapted to rotate about the subject; and a detector array, having a plurality of detector elements, adapted to acquire attenuation data for X-Rays that have been attenuated by a subject disposed between said X-Ray source and said detector array, said detector array comprising at least two types of detector element, which are differ by their spectral response. The scanner is adapted to generate images associated with the different X-Ray energy spectra.

Abstract: A method for calibration of a CT comprises sequentially positioning a phantom having a non-circular cross section and a length commensurate with the extent of a detector at a plurality of positions between an X ray source and the detector array or sequentially positioning a plurality of generally similar phantoms or sequentially positioning a same phantom at a plurality of positions between the X ray source and detector array of the CT scanner; acquiring calibration attenuation data for X rays that have been attenuated by traversing the phantom positioned at each of the plurality of positions; and calculating calibration corrections for CT scanner scan data from the calibration attenuation data.

Abstract: A CT scanner includes a first X-ray beam source, and a second X-ray beam source. With such an apparatus, first source is used to monitor buildup of an injected contrast agent in a selected region of interest relative to a patient and at least the second source is used to perform diagnostic scanning when the buildup of the contrast agent reaches a desired level.

Abstract: A CT scanner with scatter correction device and a method for scatter correction are provided. The method of correcting CT images from artifacts caused by scattered radiation comprises affixing to the non-rotating frame of the CT gantry a plurality of shields for shielding some of the CT detector elements from direct X ray radiation, while allowing scattered radiation to arrive at said shielded elements; measuring scatter signals from said shielded elements, indicative of scattered radiation intensity; and correcting for scatter by subtracting scatter intensity values estimated from said measured scatter signals from signals measured by unshielded detector elements.

Abstract: A radiation detector (24) includes a two-dimensional array of upper scintillators (30?) which is disposed facing an x-ray source (14) to convert lower energy radiation into visible light and transmit higher energy radiation. A two-dimensional array of lower scintillators (30B) is disposed adjacent the upper scintillators (30?) distally from the x-ray source (14) to convert the transmitted higher energy radiation into visible light. Respective active areas (94, 96) of each upper and lower photodetector arrays (38?, 38B) are optically coupled to the respective upper and lower scintillators (30?, 30B) at an inner side (60) of the scintillators (30?, 30B) which inner side (60) is generally perpendicular to an axial direction (Z).

Abstract: A CT scanner with scatter correction device and a method for scatter correction are provided. The method comprises positioning shields for shielding some of the CT detector elements from direct X ray radiation, while allowing scattered radiation to arrive at said shielded elements; measuring scatter signals from said shielded elements, indicative of scattered radiation intensity; and correcting for scatter by subtracting scatter intensity values estimated from said measured scatter signals from signals measured by unshielded detector elements.

Abstract: A radiation detector (24) includes a two-dimensional array of upper scintillators (30?) which is disposed facing an x-ray source (14) to convert lower energy radiation events into visible light and transmit higher energy radiation. A two-dimensional array of lower scintillators (30B) is disposed adjacent the upper scintillators (30?) distally from the x-ray source (14) to convert the transmitted higher energy radiation into visible light. Upper and lower photodetectors (38?, 30B) are optically coupled to the respective upper and lower scintillators (30?,30B) at an inner side (60) of the scintillators (30?,30B). An optical element (100) is optically coupled with the upper scintillators (30?) to collect and channel the light from the upper scintillators (30?) into corresponding upper photodetectors (38?).

Abstract: A method for calibration of a CT scanner having an x-ray source and a detector having an axial extent in the scanner, the source being rotatable about an epicenter between the source and detector, the method comprising: sequentially positioning a phantom having a non-circular cross section and a length commensurate with the extent of the detector at a plurality of positions between the X ray source and detector array of said CT scanner or sequentially positioning a plurality of phantoms each having a non-circular cross section and a length commensurate with the extent of the detector at a plurality of positions between the X ray source and detector array of said CT scanner; or sequentially positioning a same phantom having a length commensurate with the extent of the detector at a plurality of positions between the X ray source and detector array of said CT scanner or sequentially positioning a plurality of essentially similar phantoms and a length commensurate with the extent of the detector at a pluralit

Abstract: A CT scanner with scatter correction device and a method for scatter correction are provided. The method of correcting CT images from artifacts caused by scattered radiation comprises affixing to the non-rotating frame of the CT gantry a plurality of shields for shielding some of the CT detector elements from direct X ray radiation, while allowing scattered radiation to arrive at said shielded elements; measuring scatter signals from said shielded elements, indicative of scattered radiation intensity; and correcting for scatter by subtracting scatter intensity values estimated from said measured scatter signals from signals measured by unshielded detector elements.

Abstract: A CT scanner includes a first X-ray beam source, and a second X-ray beam source. With such an apparatus, first source is used to monitor buildup of an injected contrast agent in a selected region of interest relative to a patient and at least the second source is used to perform diagnostic scanning when the buildup of the contrast agent reaches a desired level.

Abstract: A radiation detector (24) includes a two-dimensional array of upper scintillators (30?) which is disposed facing an x-ray source (14) to convert lower energy radiation into visible light and transmit higher energy radiation. A two-dimensional array of lower scintillators (30B) is disposed adjacent the upper scintillators (30?) distally from the x-ray source (14) to convert the transmitted higher energy radiation into visible light. Respective active areas (94, 96) of each upper and lower photodetector arrays (38?, 38B) are optically coupled to the respective upper and lower scintillators (30?, 30B) at an inner side (60) of the scintillators (30?, 30B) which inner side (60) is generally perpendicular to an axial direction (Z).

Abstract: X-rays from an x-ray tube (16) pass through an examination region (14) and are detected by a single or two-dimensional x-ray detector (20). The x-ray detector (20) includes an array (22) of photodiodes, CCD devices, or other opto-electrical transducer elements. A matching array (24) of transparent scintillator crystals, e.g., CdWO4, is supported on and optically coupled to the photoelectric transducer array. A layer (26) of a high efficiency scintillator with a good spectral match with the opto-electrical transducer array but with limited light transmissiveness is optically coupled to the transparent scintillator array. The layer (26) is preferably zinc selenide ZnSe (Te). Electrical signals from the transducer array are reconstructed (32) into an image representation and converted into a human-readable display (38). To reduce cross-talk, the zinc selenide layer is etched with pits (40), sliced into strips (26′), cut into rectangles (26″), or has channels (44) cut into it.