Abstract: A CT system includes a gantry, an x-ray source, a detector, and a grating collimator that includes alternating first and second materials. The system includes a controller configured to emit a first beam of x-rays from a first focal spot and to a first detector pixel, wherein the first beam of x-rays passes along a ray and through one of the first materials of the grating collimator, and subsequently emit a second beam of x-rays from a second focal spot and to the first detector pixel, wherein the second beam of x-rays passes substantially along the ray and through one of the second materials of the grating collimator. The system includes a computer programmed to generate first and second kVp image datasets using data acquired from the first beam and second beams of x-rays, and reconstruct a basis material image of the object.

Abstract: A system and method include acquisition of a set of projections from an object using a CT imaging system and reconstruct an initial image of the scanned object from the set of projections, the reconstructed initial image comprising a plurality of pixels. The system and method also include identification of a candidate pixel within the plurality of pixels, application of a nonlinear enhancement to the candidate pixel to iteratively adjust an intensity value of the candidate pixel, and generation of a final image using the adjusted intensity value of the candidate pixel.

Abstract: A collimator for an imaging system includes a first region comprising a first one-dimensional array of apertures along a channel direction, and a second region comprising a second one-dimensional array of apertures along the channel direction, wherein an aspect ratio of the apertures of the first region is greater than an aspect ratio of the second region.

Abstract: An imaging system includes a rotatable gantry for receiving an object to be scanned, a generator configured to energize an x-ray source to generate x-rays, a detector positioned to receive the x-rays that pass through the object, and a computer. The computer is programmed to obtain knowledge of a metal within the object, scan the object using system scanning parameters, reconstruct an image of the object using a reconstruction algorithm, and automatically select at least one of the system scanning parameters and the reconstruction algorithm based on the obtained knowledge.

Abstract: An imaging system includes a computer programmed to estimate noise in computed tomography (CT) imaging data, correlate the noise estimation with neighboring CT imaging data to generate a weighting estimation based on the correlation, de-noise the CT imaging data based on the noise estimation and on the weighting, and reconstruct an image using the de-noised CT imaging data.

Abstract: A method is provided. The method includes acquiring a first dataset at a first energy spectrum and a second dataset at a second energy spectrum. The method also includes extracting a metal artifact correction signal using the first dataset and the second dataset or using a first reconstructed image and a second reconstructed image generated respectively from the first and the second datasets. The method further includes performing metal artifact correction on the first reconstructed image using the metal artifact correction signal to generate a first corrected image.

Abstract: A computer readable storage medium having a computer program stored thereon and representing a set of instructions that when executed by a computer causes the computer to calculate a mapping function that provides a location of each sub-volume of an imaging volume as a function of time from ultrasound data and determine a respective acquisition window for each sub-volume of the imaging volume from the mapping function. The instructions also cause the computer to reconstruct an image of the imaging volume substantially free of motion artifacts from imaging data acquired from the imaging volume.

Abstract: A method is provided. The method includes acquiring projection data of an object from a plurality of pixels, reconstructing the acquired projection data from the plurality of pixels into a reconstructed image, performing material characterization and decomposition of an image volume of the reconstructed image to reduce a number of materials analyzed in the image volume to two basis materials. The method also includes generating a re-mapped image volume for at least one basis material of the two basis materials, and performing forward projection on at least the re-mapped image volume for the at least one basis material to produce a material-based projection. The method further includes generating multi-material corrected projections based on the material-based projection and a total projection attenuated by the object, which represents both of the two basis materials, wherein the multi-material corrected projections include linearized projections.

Abstract: A method and apparatus for metal artifact elimination in a medical image. The method includes: obtaining a medical image to be processed; determining whether or not a metal region is contained in the medial image; and performing artifact elimination processing to the medical image when metal regions are contained in the medical image and a metal density value of one of the metal regions is greater than or equal to a preset density value.

Abstract: A method for reconstructing an image of an object that includes a plurality of image elements. The method includes accessing image data associated with a plurality of image elements, and reconstructing an image of the object by optimizing an objective function, where the objective function is optimized by iteratively solving a nested sequence of approximate optimization problems. The algorithm is composed of nested iterative loops, in which an inner loop iteratively optimizes an objective function approximating the outer loop objective function, and an outer loop that utilizes the solution of the inner loop to optimize the original objective function.

Abstract: A method for reconstructing an image of an object includes acquiring a set of measured projection data, reconstructing the measured projection data using a first algorithm to generate a first reconstructed image dataset, reconstructing the measured projection data using a second algorithm to generate a second reconstructed image dataset, the second algorithm being utilized to improve the temporal resolution of the second reconstructed image dataset, and generating a final image dataset using both the first and second image datasets.

Abstract: A tomographic system includes a gantry having an opening for receiving an object to be scanned, a radiation source, a detector positioned to receive radiation from the source that passes through the object, and a computer programmed to acquire a plurality of helical projection datasets of the object, reconstruct a first image using the acquired plurality of helical projection datasets and using a first reconstruction algorithm, reconstruct a second image using the acquired plurality of helical projection datasets and using a second reconstruction algorithm that is different from the first reconstruction algorithm, extract frequency components from each of the first and second images, sum the frequency components from each of the first and second images, and inverse transform the sum of the frequency components to generate a final image.

Abstract: A method is provided. The method includes acquiring a first dataset at a first energy spectrum and a second dataset at a second energy spectrum. The method also includes extracting a metal artifact correction signal using the first dataset and the second dataset or using a first reconstructed image and a second reconstructed image generated respectively from the first and the second datasets. The method further includes performing metal artifact correction on the first reconstructed image using the metal artifact correction signal to generate a first corrected image.

Abstract: A system and method include acquisition of a set of projections from an object using a CT imaging system and reconstruct an initial image of the scanned object from the set of projections, the reconstructed initial image comprising a plurality of pixels. The system and method also include identification of a candidate pixel within the plurality of pixels, application of a nonlinear enhancement to the candidate pixel to iteratively adjust an intensity value of the candidate pixel, and generation of a final image using the adjusted intensity value of the candidate pixel.

Abstract: A CT system includes an x-ray source configured to project an x-ray beam toward an object, a detector array, and a bowtie filter. The bowtie filter includes a first x-ray filtration region positioned to attenuate x-rays that pass through an isochannel of the detector array, a second x-ray filtration region positioned to attenuate x-rays that pass through channels of the detector array that are offcenter in a channel direction from the isochannel, and an x-ray attenuation material positionable to attenuate the x-rays that pass through the channels of the detector array that are offcenter in the channel direction from the isochannel. The CT system also includes a data acquisition system (DAS) connected to the detector array and configured to receive outputs from the detector array, and a computer programmed to acquire projections of imaging data of the object, and generate an image of the object using the imaging data.

Abstract: A method for reconstructing image component densities of an object includes acquiring multi-spectral x-ray tomographic data, performing a material decomposition of the multi-spectral x-ray tomographic data to generate a plurality of material sinograms, and reconstructing a plurality of material component density images by iteratively optimizing a functional that includes a joint likelihood term of at least two of the material decomposed sinograms. An x-ray tomography imaging system and a non-transitory computer readable medium are also described herein.

Abstract: A method is provided. The method includes acquiring a first dataset at a first energy spectrum and a second dataset at a second energy spectrum. The method also includes extracting a metal artifact correction signal using the first dataset and the second dataset or using a first reconstructed image and a second reconstructed image generated respectively from the first and the second datasets. The method further includes performing metal artifact correction on the first reconstructed image using the metal artifact correction signal to generate a first corrected image.

Abstract: A collimator for an imaging system includes a first region comprising a first one-dimensional array of apertures along a channel direction, and a second region comprising a second one-dimensional array of apertures along the channel direction, wherein an aspect ratio of the apertures of the first region is greater than an aspect ratio of the second region.

Abstract: Methods and apparatus for statistical iterative reconstruction are provided. One method includes pre-processing acquired raw measurement data to modify the raw data measurement data and determining a change in a variance of the raw measurement data resulting from the modification to the raw measurement data during pre-processing. The method also includes reconstructing an image using the modified raw measurement data resulting from the pre-processing and the determined change in variance.

Abstract: An imaging system includes a rotatable gantry for receiving an object to be scanned, a generator configured to energize an x-ray source to generate x-rays, a detector positioned to receive the x-rays that pass through the object, and a computer. The computer is programmed to obtain knowledge of a metal within the object, scan the object using system scanning parameters, reconstruct an image of the object using a reconstruction algorithm, and automatically select at least one of the system scanning parameters and the reconstruction algorithm based on the obtained knowledge.