Abstract: Techniques for counting respective photons having energy levels within at least a first energy window and a second energy window, where the first energy window is lower than the second energy window, are presented. The techniques include: receiving a first indication of a first photon detection, the first photon detection being of a photon having an energy of at least a lower end of the first energy window; receiving a second indication of a second photon detection, the second photon detection being of a photon having an energy of at least a lower end of the second energy window; within a predetermined time interval of the receiving the first indication, communicating locally the second indication to counter logic for the first energy window, where a counter for the first energy window is not incremented; and incrementing a counter for an energy window higher than the first energy window.

Abstract: A method, a system, a device, and a computer program produce for photon detection is disclosed. The method includes receiving, by a plurality of anodes, a photon via one or more of the plurality of anodes; measuring respective voltages of the photon at each of the plurality of anodes; counting incidents in which the photon is detected by more than one of the plurality of anodes based on the measuring; and outputting information regarding a counted number of incidents in which the photon is detected by more than one of the plurality of anodes, wherein the information regarding the courted number of incidents in which the photon is detected by more than one of the plurality of anodes is used as part of a production of an image associated with the received photon.

Abstract: The present invention is directed to a new joint estimation framework employing MAP estimation based on pixel-based latent variables for tissue types. The method combines the geometrical information described by latent MRF, statistical relation between tissue types and P-C coefficients, and Poisson noise models of PCD data, and makes possible the continuous Baysian estimation from detected photon counts. The proposed method has better accuracy and RMSE than the method using FBP and thresholding. The joint estimation framework has the potential to further improve the accuracy by introducing more information about tissues in human body, e.g., the location, size, and number of tissues, or limited variation of neighboring tissues, which will be easily formulated by pixel-based latent variables.

Abstract: An embodiment in accordance with the present invention provides a new SR compensation (SRC) method, using a more efficient conjugate gradient method. In this method, the first and second derivatives are directly calculated analytically. The proposed SRC uses a sinogram restoration approach, integrates the SRF as a part of a forward imaging model, and compensates for the effect of the SR by maximizing the Poisson log-likelihood of measurements. The algorithm can be evaluated using as a simulated fan-beam x-ray CT scanner.

Abstract: Featured are methods for reconstruction of images acquired from any of a number of scanning devices or apparatuses known to those skilled in the art which methods are established so as to provide a mechanism for compensating for motion of an object being imaged. Such methods of the present invention are such as to allow the clinician to select one or more specific methodologies that is appropriate for the expected motion, severity or complexity of the motion and efficient processing of projection data. Also feature are systems, apparatuses, software code and computer readable media which embody such methodologies.

Abstract: An embodiment in accordance with the present invention provides a new SR compensation (SRC) method, using a more efficient conjugate gradient method. In this method, the first and second derivatives are directly calculated analytically. The proposed SRC uses a sinogram restoration approach, integrates the SRF as a part of a forward imaging model, and compensates for the effect of the SR by maximizing the Poisson log-likelihood of measurements. The algorithm can be evaluated using as a simulated fan-beam x-ray CT scanner.

Abstract: The present invention is directed to a new joint estimation framework employing MAP estimation based on pixel-based latent variables for tissue types. The method combines the geometrical information described by latent MRF, statistical relation between tissue types and P-C coefficients, and Poisson noise models of PCD data, and makes possible the continuous Baysian estimation from detected photon counts. The proposed method has better accuracy and RMSE than the method using FBP and thresholding. The joint estimation framework has the potential to further improve the accuracy by introducing more information about tissues in human body, e.g., the location, size, and number of tissues, or limited variation of neighboring tissues, which will be easily formulated by pixel-based latent variables.

Abstract: A pickup 1 generates a video signal based on an arbitrarily set frame rate. A frame rate converter 2 converts a frame rate of the video signal output from the pickup 1 into a predetermined frame rate. Frame rate conversion information output units 6 and 4 output information on frame rate conversion in a manner corresponding to a video signal after the frame rate conversion.

Abstract: Featured are methods for reconstruction of images acquired from any of a number of scanning devices or apparatuses known to those skilled in the art which methods are established so as to provide a mechanism for compensating for motion of an object being imaged. Such methods of the present invention are such as to allow the clinician to select one or more specific methodologies that is appropriate for the expected motion, severity or complexity of the motion and efficient processing of projection data. Also feature are systems, apparatuses, software code and computer readable media which embody such methodologies.

Abstract: A method of removing an imaging artifact in a medical image, including obtaining a first plurality of images, the first plurality of images collectively defining a first image volume; filtering the first plurality of images to create a second plurality of images, each image in the second plurality of images comprising an average of at least two images in the first plurality of images; selecting a first image from the first plurality of images; adding a lost noise image to a second image in the second plurality of images to create a noise restored image, the second image in the second plurality of images corresponding to the first image in the first plurality of images; determining a gradient image based on pixel values in the second plurality of images, the gradient image comprising a gradient value at each pixel location in the second image; and combining, based on the determined gradient image, the first image and the noise restored image to obtain a corrected image that does not contain the imaging artifac

Abstract: A method of determining an image data value at a point of reconstruction in a computed tomography (CT) image of a scanned object, including obtaining projection data of the scanned object, filtering the obtained projection data with a one-dimensional ramp filter to generate ramp-filtered data, and applying a backprojection operator with inverse distance weighting to the ramp-filtered data to generate the image data value at the point of reconstruction in the CT image.

Abstract: A computed tomography apparatus, including: an X-ray helical scanning device including an X-ray generator and an X-ray detector arranged in a gantry, the helical scanning device configured to provide a continuous scan and to obtain projection data of a scanned object arranged on a platform; and control unit configured to control at least one of the X-ray helical scanning device and the platform so as to generate the continuous scan with a helical pitch that is based on a height of a detector row of the X-ray detector projected onto an iso-center of the gantry.

Abstract: A method, system, and computer program product for compensating for the unavailability of projection data of a scanned object at a selected point, the selected point located outside a detection range of a detector. The method include the steps of obtaining projection data of the scanned object, and compensating for the unavailability of the projection data at the selected point based on the obtained projection data and coordinates of the selected point relative to the detector. The compensating step includes determining at least one complementary projection angle and coordinates of at least one complementary point based on a source projection angle and the coordinates of the selected point relative to the detector, and estimating the projection data value at the selected point based on the acquired projection data, the at least one complementary projection angle, and the coordinates of the at least one complementary point.

Abstract: A computed tomography apparatus, including: an X-ray helical scanning device including an X-ray generator and an X-ray detector arranged in a gantry, the helical scanning device configured to provide a continuous scan and to obtain projection data of a scanned object arranged on a platform; and control unit configured to control at least one of the X-ray helical scanning device and the platform so as to generate the continuous scan with a helical pitch that is based on a height of a detector row of the X-ray detector projected onto an iso-center of the gantry.

Abstract: An X-ray computed tomography apparatus includes a helical scanning device configured to collect projection data while at least one of a gantry and a couch moves along a body axial direction of an object on the couch when at least one of the gantry and the couch is tilted, the helical scanning device including an X-ray source configured to generate X-rays, and a detector disposed opposite the X-ray source and having detector elements arranged in a plurality of rows along the body axial direction, and a reconstructing device configured to reconstruct an image based on the projection data using cone-beam Feldkamp reconstruction.

Abstract: A method for reconstructing an image, including obtaining projection data using an X-ray detector and one of a cone-beam X-ray generator and a fan-beam X-ray generator; filtering the obtained projection data using a ramp-based filtering function to generate filtered projection data; weighting the filtered projection data to compensate for redundant projection data; and reconstructing the image by back-projecting the weighted projection data along a radial path.

Abstract: A method, system, and computer program product for compensating for the unavailability of projection data of a scanned object at a selected point, the selected point located outside a detection range of a detector. The method include the steps of obtaining projection data of the scanned object, and compensating for the unavailability of the projection data at the selected point based on the obtained projection data and coordinates of the selected point relative to the detector. The compensating step includes determining at least one complementary projection angle and coordinates of at least one complementary point based on a source projection angle and the coordinates of the selected point relative to the detector, and estimating the projection data value at the selected point based on the acquired projection data, the at least one complementary projection angle, and the coordinates of the at least one complementary point.

Abstract: A method of determining an image data value at a point of reconstruction in a computed tomography (CT) image of a scanned object, including obtaining projection data of the scanned object, filtering the obtained projection data with a one-dimensional ramp filter to generate ramp-filtered data, and applying a backprojection operator with inverse distance weighting to the ramp-filtered data to generate the image data value at the point of reconstruction in the CT image.

Abstract: A method of removing an imaging artifact in a medical image, including obtaining a first plurality of images, the first plurality of images collectively defining a first image volume; filtering the first plurality of images to create a second plurality of images, each image in the second plurality of images comprising an average of at least two images in the first plurality of images; selecting a first image from the first plurality of images; adding a lost noise image to a second image in the second plurality of images to create a noise restored image, the second image in the second plurality of images corresponding to the first image in the first plurality of images; determining a gradient image based on pixel values in the second plurality of images, the gradient image comprising a gradient value at each pixel location in the second image; and combining, based on the determined gradient image, the first image and the noise restored image to obtain a corrected image that does not contain the imaging artifac

Abstract: An X-ray computerized tomographic apparatus includes an X-ray tube device configured to irradiate an object to be examined with a pyramidal X-ray beam, a detector which has a plurality of detecting elements arrayed in a slice direction in which X-rays transmitted through the object are detected, a data extending unit which creates virtual data corresponding to an extension region located outside a region in which the detecting elements are arranged in the slice direction on the basis of real data detected by the detecting element, and a reconstructing unit which reconstructs image data on the basis of the real data and virtual data.