Patent application number | Description | Published |
20090190814 | METHOD AND SYSTEM FOR IMAGE RECONSTRUCTION - Disclosed is an imaging system including a source generating an x-ray beam, a detector array receiving the x-ray beam and generating projection data, a translatable table configured for disposal of an object thereon and operable to translate in relation to the source and the detector array, the source and the detector array rotating about the translatable table to scan the object, and an image reconstructor electrically coupled to the detector array and configured to reconstruct an image in response to the projection data via an iterative reconstruction technique configured to perform a targeted statistical reconstruction. | 07-30-2009 |
20090232269 | METHODS AND APPARATUS FOR NOISE ESTIMATION FOR MULTI-RESOLUTION ANISOTROPIC DIFFUSION FILTERING - A method for reducing noise in a computed tomographic (CT) image includes acquiring both a first set of projection views and a second set of projection views, wherein for each projection view in the first set of projection views there is an associated projection view in the second set of projection views representing the same object scanned at substantially the same time from substantially the same position. The method further includes reconstructing the first set of projection views and the associated second set of projection views to obtain a first image and a second image, respectively. Next, the first image and the second image are combined to obtain a noise map and an amount of noise in a product image is estimated utilizing the noise map. The method also includes filtering using the noise map to perform noise reduction. | 09-17-2009 |
20090238427 | Method and Apparatus for Correcting Multi-Modality Imaging Data - A method for correcting Positron Emission Tomography (PET) data includes adjusting a tube current generated by the CT imaging system to a second tube current value that is less than a first tube current value used to generate diagnostic quality CT images, and imaging the patient with the CT imaging system set at the second tube current value. The method also includes generating a plurality of computed tomography (CT) projection data from the CT imaging system and preprocessing the CT projection data to generate preprocessed CT projection data. The method further includes filtering the preprocessed CT projection data to reduce electronic noise to generate filtered CT projection data, and performing a minus logarithmic operation on the filtered CT projection data to generate the corrected PET data. | 09-24-2009 |
20100054394 | METHOD AND SYSTEM FOR IMAGE RECONSTRUCTION - A method and system for image reconstruction of data acquired by a device such as computed tomography is provided. The method and system use a multi-stage statistical iterative reconstruction techniques to provide a three dimensional representation of the scanned object. In one embodiment, the first stage uses a projection-based reconstruction technique, such as Ordered Subset (OS) to converge on a solution for low frequency portion of the image. A subsequent stage uses a voxel-based reconstruction technique, such as Iterative Coordinate Descent (ICD), to converge on a solution for high frequency portions of the image. Systems and methods for reconstructing images from incomplete or partial projection data is also provided. | 03-04-2010 |
20100215140 | METHODS AND SYSTEMS TO FACILITATE CORRECTING GAIN FLUCTUATIONS IN ITERATIVE IMAGE RECONSTRUCTION - Methods and systems for reconstructing an image are provided. The method includes performing a tomographic image reconstruction using a joint estimation of at least one of a gain parameter and an offset parameter, and an estimation of the reconstructed image. | 08-26-2010 |
20100246760 | COMBINING X-RAY AND ULTRASOUND IMAGING FOR ENHANCED MAMMOGRAPHY - A mammography system includes a patient support with a breast opening. Beneath the patient support, an x-ray source transmits x-rays through a breast of a patient extending through the opening. An opposing x-ray detector receives the x-rays to obtain an x-ray image of the breast. The x-ray source and x-ray detector rotate around the opening while maintaining a fixed relation relative to one another, and a container is filled with a fluid and positioned proximate to and aligned with the opening to receive the breast. An ultrasound transmitter transmits sound waves through the breast when positioned within the fluid. An opposing ultrasound receiver receives the sound waves to obtain an ultrasound image of the breast. In a preferred embodiment, the mammography system positions the ultrasound transmitter and/or ultrasound receiver at a first position when obtaining the x-ray image of the breast and a second position when obtaining the ultrasound image of the breast. In other preferred embodiments, mammography methods correspond thereto. | 09-30-2010 |
20110142314 | SYSTEM AND METHOD OF INCREASING TEMPORAL RESOLUTION OF AN X-RAY IMAGE - 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. | 06-16-2011 |
20110142315 | SYSTEM AND METHOD FOR TOMOGRAPHIC DATA ACQUISITION AND IMAGE RECONSTRUCTION - 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. The computer is programmed to acquire a plurality of projection datasets of the object, define a temporal subset of projection datasets from the plurality of projection datasets, reconstruct a working image of the object using the plurality of projection datasets, identify a region of motion in the working image, and minimize motion artifacts in the region of motion in the working image using the temporal subset of projection datasets. | 06-16-2011 |
20110150308 | SYSTEM AND METHOD OF ITERATIVE IMAGE RECONSTRUCTION FOR COMPUTED TOMOGRAPHY - A system and method include acquisition of a set of image data corresponding to a time period of data acquisition, the set of image data corresponding to a plurality of voxels, wherein each of the plurality of voxels corresponds to a distinct acquisition time within the time period of data acquisition. The system and method further include the modeling of the plurality of voxels as a function of time based on a plurality of kinetic parameters associated therewith and reconstruction of an image from the set of image data based on the modeled plurality of voxels. | 06-23-2011 |
20120314928 | SYSTEM AND METHOD OF INCREASING TEMPORAL RESOLUTION OF AN X-RAY IMAGE - 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. | 12-13-2012 |
20130010917 | SYSTEM AND METHOD OF ITERATIVE IMAGE RECONSTRUCTION FOR COMPUTED TOMOGRAPHY - A non-transitory computer readable storage medium having stored thereon a computer program having instructions, which, when executed by a computer, cause the computer to acquire a set of projection data corresponding to a plurality of image voxels and to calculate coefficients of a regularizing function configured to penalize differences between pairs of the plurality of voxels that are not immediate neighbors. The instructions also cause the computer to iteratively reconstruct an image from the set of projection data based on the regularizing function. | 01-10-2013 |
20130343672 | METHOD AND APPARATUS FOR ITERATIVE RECONSTRUCTION - A method is provided for reconstructing an image of an object that includes image elements. The method includes accessing measurement data associated with the image elements, introducing an auxiliary variable to transform an original problem of reconstructing the image to a constrained optimization problem, and solving the constrained optimization problem using a method of multipliers to create a sequence of sub-problems and solve the sequence of sub-problems. Solving the sequence of sub-problems includes reconstructing the image by optimizing a first objective function. The first objective function is optimized by iteratively solving a nested sequence of approximate optimization problems. An inner loop iteratively optimizes a second objective function approximating the first objective function. An outer loop utilizes the solution of the second objective function to optimize the first objective function. | 12-26-2013 |
20130343673 | METHOD AND APPARATUS FOR ITERATIVE RECONSTRUCTION - A method is provided for iteratively reconstructing an image of an object. The method includes accessing measurement data associated with the image, and using a simultaneous algorithm to reconstruct the image. Using the simultaneous algorithm to reconstruct the image includes determining a scaling factor that is voxel-dependent, and applying the voxel-dependent scaling factor to a gradient of an objective function to reconstruct the image. | 12-26-2013 |
20140161340 | ITERATIVE RECONSTRUCTION - An improved iterative reconstruction method to reconstruct a first image includes generating an imaging beam, receiving said imaging beam on a detector array, generating projection data based on said imaging beams received by said detector array, providing said projection data to an image reconstructor, enlarging one of a plurality of voxels and a plurality of detectors of the provided projection data, reconstructing portions of the first image with the plurality of enlarged voxels or detectors, and iteratively reconstructing the portions of the first image to create a reconstructed image. | 06-12-2014 |
20140369463 | SYSTEM AND METHOD OF ITERATIVE IMAGE RECONSTRUCTION FOR COMPUTED TOMOGRAPHY - A system and method include acquisition of projection data from a scanned object, the set of projection data comprising a plurality of projection measurements. The system and method also include calculation of a set of modified statistical weights from the projection data, wherein a respective modified statistical weight of the set of modified statistical weights comprises a deviation from an inverse variance of a corresponding projection measurement of the projection data. The system and method further include reconstruction of an image of the scanned object using the set of modified statistical weights as coefficients in an iterative reconstruction algorithm. | 12-18-2014 |
Patent application number | Description | Published |
20110150305 | METHOD AND SYSTEM FOR CORRECTING ARTIFACTS IN IMAGE RECONSTRUCTION - Methods and systems are provided for correcting artifacts in iterative reconstruction processes. In certain embodiments, weighting schemes may be applied such that less than all of the available scan or projection data is utilized in the iterative reconstruction. In this manner, inconsistencies in the data undergoing reconstruction may be reduced. | 06-23-2011 |
20130108128 | METHOD AND APPARATUS FOR ITERATIVE RECONSTRUCTION | 05-02-2013 |
20130121553 | METHOD AND APPARATUS FOR STATISTICAL ITERATIVE RECONSTRUCTION - 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. | 05-16-2013 |
20130343624 | METHODS AND SYSTEMS FOR PERFORMING MODEL-BASED ITERATIVE RECONSTRUCTION - 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. | 12-26-2013 |
20140205171 | METHOD AND SYSTEM FOR CORRECTING ARTIFACTS IN IMAGE RECONSTRUCTION - Methods and systems are provided for correcting artifacts in iterative reconstruction processes. In certain embodiments, weighting schemes may be applied such that less than all of the available scan or projection data is utilized in the iterative reconstruction. In this manner, inconsistencies in the data undergoing reconstruction may be reduced. | 07-24-2014 |
20140369580 | ACCELERATED ITERATIVE RECONSTRUCTION - A framework for an iterative reconstruction algorithm is described which combines two or more of an ordered subset method, a preconditioner method, and a nested loop method. In one type of implementation a nested loop (NL) structure is employed where the inner loop sub-problems are solved using ordered subset (OS) methods. The inner loop may be solved using OS and a preconditioner method. In other implementations, the inner loop problems are created by augmented Lagrangian methods and then solved using OS method. | 12-18-2014 |
20140369581 | ITERATIVE RECONSTRUCTION IN IMAGE FORMATION - The use of the channelized preconditioners in iterative reconstruction is disclosed. In certain embodiments, different channels correspond to different frequency sub-bands and the output of the different channels can be combined to update an image estimate used in the iterative reconstruction process. While individual channels may be relatively simple, the combined channels can represent complex spatial variant operations. The use of channelized preconditioners allows empirical adjustment of individual channels. | 12-18-2014 |