Abstract: Disclosed is a collimator assembly for a multi-radiation-source medical imaging system (e.g. CT) and a medical imaging system utilizing the collimator. According to some embodiments of the present invention, there is provided a collimator assembly including at least two apertures, which apertures are adjustable substantially synchronously by one or more actuators.

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 method of correcting CT numbers in image data includes selecting at least one reference region in a CT image, wherein the selected region is a region associated with substantially same CT number when no artifacts are present in the CT image, estimating artifacts in at least one other region of the CT image based at least in part on detected CT numbers in the at least one reference region, and correcting CT numbers in the at least one other region of the CT image based on the estimated artifacts.

Abstract: A CT scanner comprising: a rotor rotatable about an axis of rotation: an X-ray source mounted to the rotor having a focal spot from which an X-ray beam emanates; an X-ray detector array comprising a plurality of X-ray detectors for detecting X-rays in the X-ray beam; wherein the detector array has at least one high resolution region in which detectors have a high packing density and at least one low resolution region in which detectors have a low packing density and are separated by X-ray insensitive regions substantially larger than insensitive regions resulting from septa between detectors that function to reduce detector cross talk.

Abstract: An X-ray tube system comprising: at least one filament adapted to produce two electron beams when electrified; at least two anodes spaced from each other along a first direction that each comprises a face that receives an electron beams from the at least one filament at a focal point and produces x-ray cone beams responsive thereto, the x-ray beams being directed in a same direction perpendicular to the first direction; a collimator that collimates the cone beams such that the beams are asymmetric, with the side of each beam distal from the other beam having a smaller beam angle than the side proximal to the other beam.

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 CT scanner comprises at least one cone beam x-ray source assembly mounted on a gantry frame, the gantry frame rotatable about a rotation axis, the x-ray source assembly operable to emit a cone beam at an orientation with respect to the rotation axis, and a controller operable to adjust an orientation of the cone beam during a rotation cycle of the gantry, wherein the controller adjusts the orientation to radiate a substantially same volume of interest over the rotation cycle.

Abstract: An X-ray source system for a CT scanner includes a plurality of X-ray sources, wherein each X-ray source of the plurality is provided with a cathode from which an electron beam is emitted, an anode to receive the electron beam and at least one grid electrode, wherein the grid electrodes are configured to selectably block radiation from said X-ray sources; a high voltage generator for applying voltage to the plurality of X-ray sources, wherein each of the plurality of X-ray sources are configured to present substantially the same load to the high voltage generator; a grid modulator configured to apply voltage to grid electrodes of each of the plurality of X-ray sources in turn; and a controller for controlling the grid modulator so that only one of the plurality of X-ray sources emits radiation at any one time.

Abstract: Disclosed are methods, circuits, devices, assemblies and systems for performing Computer Tomography (CT)—for example of a periodically moving object such as a heart. According to some embodiments, there is provided a Computer Tomography scanner which includes an x-ray source adapted to generate an x-ray scan beam and a electromechanical assembly to which the x-ray source is mounted. The assembly may be adapted to move one or more electromechanical elements such that the scan beam is moved around the periodically moving object with a velocity profile having both constant and cyclically alternating rotational velocity components, and wherein the cyclically alternating velocity components are synchronized with the periodic motion of the object.

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 CT scanner comprising: a rotor rotatable about an axis of rotation: an X-ray source mounted to the rotor having a focal spot from which an X-ray beam emanates; an X-ray detector array comprising a plurality of X-ray detectors for detecting X-rays in the X-ray beam; wherein the detector array has at least one high resolution region in which detectors have a high packing density and at least one low resolution region in which detectors have a low packing density and are separated by X-ray insensitive regions substantially larger than insensitive regions resulting from septa between detectors that function to reduce detector cross talk.

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 comprising: a rotor rotatable about an axis of rotation: an X-ray source mounted to the rotor having a focal spot from which an X-ray beam emanates; an X-ray detector array comprising a plurality of X-ray detectors for detecting X-rays in the X-ray beam; wherein the detector array has at least one high resolution region in which detectors have a high packing density and at least one low resolution region in which detectors have a low packing density and are separated by X-ray insensitive regions substantially larger than insensitive regions resulting from septa between detectors that function to reduce detector cross talk.

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: Disclosed are methods, circuits, devices, assemblies and systems for performing Computer Tomography (CT)—for example of a periodically moving object such as a heart. According to some embodiments, there is provided a Computer Tomography scanner which includes an x-ray source adapted to generate an x-ray scan beam and a electromechanical assembly to which the x-ray source is mounted. The assembly may be adapted to move one or more electromechanical elements such that the scan beam is moved around the periodically moving object with a velocity profile having both constant and cyclically alternating rotational velocity components, and wherein the cyclically alternating velocity components are synchronized with the periodic motion of the object.

Abstract: A method for tracking position of a feature in a subject is provided comprising operating a CT scanner to generate and display CT images of a volume within the subject and operating the CT scanner to generate projection X-Ray images of the volume. The X-Ray images are responsive to X-Ray emitted by two X-Ray sources displaced from each other. The method further comprises generating and displaying stereoscopic images from said projection X-Ray images, wherein the stereoscopic images are spatially registered to the CT images.

Abstract: Disclosed is a Computer Tomography (CT) system including a gantry having first and second semicircular support elements which are concentric with one another. Each of the first and second semicircular support elements has a missing sector and at least one of the missing sectors may be of an angle of 180 degrees or less. A controller may be adapted to regulate relative rotational positions between said first and second support elements.

Abstract: A CT scanner for scanning a subject is provided, the scanner comprising: a gantry capable of rotating about a scanned subject; at least two cone beam X-Ray sources displaced from each other mounted on said gantry; at least one 2D detector array mounted on said gantry, said detector is capable of receiving radiation emitted by said at least two X-Ray sources and attenuated by the subject to be scanned; a first image processor capable of generating and displaying CT images of a volume within the subject; a second image processor capable of generating projection X-Ray images of said volume, wherein the images are responsive to X-Ray separately emitted by each of said at least two cone beam X-Ray sources; and a third image processor capable of generating and displaying fluoroscopic images composed of said projection X-Ray images, wherein said fluoroscopic images are spatially registered to said CT images.

Abstract: A method of correcting CT numbers in image data includes selecting at least one reference region in a CT image, wherein the selected region is a region associated with substantially same CT number when no artifacts are present in the CT image, estimating artifacts in at least one other region of the CT image based at least in part on detected CT numbers in the at least one reference region, and correcting CT numbers in the at least one other region of the CT image based on the estimated artifacts.