摘要:
A method for reconstructing images of structures undergoing physiological motion comprises acquiring a first volume of data over a first motion cycle. The first volume comprises a first overlap volume. A second volume of data is acquired over a second motion cycle and comprises a second overlap volume. The first and second overlap volumes comprise like anatomical regions with respect to each other. A reconstructed volume of data is formed based on temporal data within the first and second overlap volumes.
摘要:
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.
摘要:
A CT system includes a rotatable gantry having an opening to receive an object to be scanned, an x-ray source configured to project an x-ray beam toward the object having a primary intensity, a detector configured to detect high frequency electromagnetic energy passing through the object and output imaging data, and a data acquisition system (DAS) connected to the detector and configured to receive the imaging data. The system also includes a computer programmed to obtain image projection data of the object from the DAS, correct the projection data using a scatter function that is based at least on a known characteristic of the x-ray beam, and generate images using the corrected projection data.
摘要:
A CT system includes a generator configured to energize an x-ray source to a first kilovoltage (kVp) and to a second kVp, and a computer that is programmed to acquire a first view dataset with the x-ray source energized to the first kVp and a second view dataset with the x-ray source energized to the second kVp, generate a base correction image using the first view dataset and the second view dataset, and reconstruct a pair of base material images from the first view dataset and from the second view dataset. The computer is also programmed to estimate artifact correlation in the pair of base material images using the base correction image, generate a pair of final base material images and a final monochromatic image, and correct one of the pair of final base material images and the final monochromatic image at a keV value using the estimated artifact correlation.
摘要:
A computerized tomographic system configured to acquire short scan data of an object within a single revolution of a detector array about the object over a first angular range of rotation of the detector array about the object, define a temporal subset of the acquired short scan data over a second angular range of rotation of the detector that is less than the first angular range of rotation, generate a mathematical function that is based on the acquired short scan data and the defined temporal subset of data, minimize the mathematical function, and generate an image of the object using the minimized mathematical function and the data acquired over the second angular range of rotation of the detector.
摘要:
A method for reconstructing an image of an object includes scanning an object using a computed tomographic (CT) imaging apparatus to acquire projections of the object. A set of thresholds are determined utilizing the projections, and selected smoothing kernels are associated with the thresholds. The method further includes utilizing the smoothing kernels and the projections to produce smoothed projections in accordance with the thresholds and filtering and backprojecting the smoothed projections to generate an image of the object.
摘要:
A system, method, and apparatus includes a computed tomography (CT) system having a rotatable gantry, an x-ray source, a generator, a detector having pixels and positioned to receive x-rays, and a computer. The computer is programmed to acquire CT data representative of an object, determine a first subset of the CT data, determine a second subset of the CT data, and determine a difference between the first and second subsets of the CT data to identify a motion region in the object. The computer is also programmed to update image data reconstructed from a first portion of the first subset of the CT data and corresponding to the region and reconstruct an image based on the updated image data and non-updated image data. The non-updated image data is reconstructed from a second portion the first subset of the CT data.
摘要:
A method for calibrating a medical imaging system includes performing an initial calibration of the imaging system, at a manufacturing site fabricating the imaging system, using a plurality of phantoms, shipping one of the phantoms to an installation site installing the imaging system, and performing a final calibration, at an installation site of the imaging system, using the shipped phantom. A set of calibration phantoms is also described herein.
摘要:
A CT system includes a rotatable gantry having an opening for receiving an object to be scanned, and a controller configured to obtain kVp projection data at a first kVp, obtain kVp projection data at a second kVp, extract data from the kVp projection data obtained at the second kVp, add the extracted data to the kVp projection data obtained at the first kVp to generate mitigated projection data at the first kVp, and generate an image using the mitigated projection data at the first kVp and using the projection data obtained at the second kVp.
摘要:
The present disclosure relates to the generation of dual-energy X-ray data using a data sampling rate comparable to the rate utilized for single-energy imaging. In accordance with the present technique a reduced kVp switching rate is employed compared to conventional dual-energy imaging. Full angular resolution is achieved in the generated images.