Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into the image reconstruction process. Thus, one aspect of the present invention is to provide an image reconstruction method that requires less number of data samples to reconstruct an accurate reconstruction of a desired image than previous methods, such as, compressed sensing. Another aspect of the invention is to provide an image reconstruction method that imparts the signal-to-noise ratio of a prior image to the desired image being reconstructed. Another aspect of the invention is to provide an image reconstruction method that, when practiced in the field of x-ray imaging, allows for exposing a subject to substantially less radiation dose than is required in conventional x-ray imaging techniques.

Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into the image reconstruction process. Thus, one aspect of the present invention is to provide an image reconstruction method that requires less number of data samples to reconstruct an accurate reconstruction of a desired image than previous methods, such as, compressed sensing. Another aspect of the invention is to provide an image reconstruction method that imparts the signal-to-noise ratio of a prior image to the desired image being reconstructed. Another aspect of the invention is to provide an image reconstruction method that, when practiced in the field of x-ray imaging, allows for exposing a subject to substantially less radiation dose than is required in conventional x-ray imaging techniques.

Abstract: An image reconstruction method for cardiac cone beam CT is provided, in which data acquired as truncated projections using current cardiac flat panel detectors is reconstructed to form a high quality image of a desired cardiac phase. An iterative method is utilized to reconstruct a prior image from all of the acquired truncated data without cardiac gating. Subsequently, a reconstruction method, in which the prior image is utilized in a prior image constrained reconstruction method, is utilized to reconstruct images for each individual cardiac phase. The objective function in such a prior image constrained reconstruction method is modified to incorporate the conditions used in the production of the prior image so that the data truncation problem is properly addressed.

Abstract: 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.

Abstract: An image reconstruction method applicable to a number of different imaging modalities including magnetic resonance imaging (MRI), x-ray computed tomography (CT), positron emission tomography (PET), and single photon emission computed tomography (SPECT) is disclosed. A sparsifying image is reconstructed from a series of acquired undersampled data to provide a priori knowledge of a subject being imaged. An iterative reconstruction process is further employed to iteratively determine a correction image for a given image frame that, when subtracted from the sparsifying image, produces a quality image for the image frame.

Abstract: A method for producing an image having a high signal-to-noise ratio (SNR) is provided. An image to be enhanced is provided, the provided image including a previously reconstructed image or an image reconstructed from acquired image data. A prior image is produced from the provided image, for example, by filtering the provided image such that noise from the provided image is substantially suppressed in the prior image. Synthesized image data is produced by performing a forward projection of the provided image. A sparsified image is produced by subtracting the prior image and the provided image. A target image having a higher SNR than the provided image is reconstructed using the sparsified image, the provided image, and the synthesized image data. The provided image may be, for example, a medical image produced by an x-ray imaging system, including computed tomography and C-arm systems; a magnetic resonance imaging system; and the like.

Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into an iterative image reconstruction process as well as utilizing an image frame from a previous time frame to constrain the reconstruction of a current image frame.

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 short scan angular range of data of the object, and define a temporal subset of the acquired short scan angular range of data for image reconstruction, the defined temporal subset of the acquired short scan angular range of data comprising approximately half of the angular range of the short scan angular range of data. The computer is programmed to reconstruct a prior image using the acquired short scan angular range of data, and input an estimated image of the object and the prior image into an objective function and minimize the objective function to reconstruct a refined image using the defined temporal subset of scan data and the prior image.

Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into the image reconstruction process. Thus, one aspect of the present invention is to provide an image reconstruction method that requires less number of data samples to reconstruct an accurate reconstruction of a desired image than previous methods, such as, compressed sensing. Another aspect of the invention is to provide an image reconstruction method that produces a time series of desired images indicative of a higher temporal resolution than is ordinarily achievable with the imaging system. For example, cardiac phase images can be produced with high temporal resolution (e.g., 20 milliseconds) using a CT imaging system with a slow gantry rotation speed.

Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into the image reconstruction process. One aspect of the invention is to provide an image reconstruction method that produces a time series of desired images indicative of a higher temporal resolution than is ordinarily achievable with the imaging system, while mitigating undesired image artifacts. This is generally achieved by incorporating a limited amount of additional image data into the data consistency condition imposed during a prior image constrained image reconstruction. For example, cardiac phase images can be produced with high temporal resolution using a state-of-the-art multi-detector CT system with either fast gantry rotation speed or CT imaging system with a slow gantry rotation speed.

Abstract: A method for reconstructing an image of a subject with a medical imaging system is provided. Image data is acquired with the medical imaging system, typically in an undersampled manner. A prior image constrained compressed sensing (PICCS) image reconstruction method is then implemented to reconstruct images of the subject being imaged. The prior image used in such a method is produced from so-called averaged image data. The averaged image data is produced by effectively averaging signal information associated with a plurality of different slice locations along a direction orthogonal to the plane parallel to the slice locations. Weightings are calculated from images reconstructed in a conventional manner from the acquired image data, and these weightings are employed to produce the averaged image data. By producing a prior image in this manner, a higher signal-to-noise ratio is achievable, allowing trade-offs with factors such as radiation dose in x-ray imaging.

Abstract: A line scan cone beam CT imaging system irradiates an object with an x-ray cone beam for multiple views. A projection data set of the object is acquired at each view. Between views, the cone beam and detector array are translated along parallel lines in opposite directions. An image is generated by converting the cone beam projection data set of the real object into a parallel-beam projection data set corresponding to a virtual object and using a total variation minimization image reconstruction algorithm to reconstruct a virtual image of the virtual object. The reconstruction algorithm includes the constraint that the Fourier transform of the reconstructed virtual image matches the known Fourier coefficients in the set of converted parallel-beam projections of the virtual object. The reconstructed virtual image is then transformed into an image of the real object.

Abstract: A system and method for generating an image of an object that is substantially free of artifacts induced by missing data is disclosed. The method includes performing a computed tomography (CT) imaging process using a cone-beam traversed over an actual scan path to acquire actual CT data having missing data. The method also includes reconstructing an initial image of a volume of interest (VOI) using the actual CT data, with the initial reconstructed image having artifacts attributable to the missing data, and reprojecting the reconstructed image of the VOI onto a virtual scan path to at least acquire virtual data corresponding to the missing data. Further, the method includes reconstructing an improved image of the VOI using the actual CT data and the virtual data, with the artifacts reduced in the improved reconstructed image.

Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into the image reconstruction process. One aspect of the invention is to provide an image reconstruction method that produces a time series of desired images indicative of a higher temporal resolution than is ordinarily achievable with the imaging system, while mitigating undesired image artifacts. This is generally achieved by incorporating a limited amount of additional image data into the data consistency condition imposed during a prior image constrained image reconstruction. For example, cardiac phase images can be produced with high temporal resolution using a state-of-the-art multi-detector CT system with either fast gantry rotation speed or CT imaging system with a slow gantry rotation speed.

Abstract: An image reconstruction method for cardiac cone beam CT is provided, in which data acquired as truncated projections using current cardiac flat panel detectors is reconstructed to form a high quality image of a desired cardiac phase. An iterative method is utilized to reconstruct a prior image from all of the acquired truncated data without cardiac gating. Subsequently, a reconstruction method, in which the prior image is utilized in a prior image constrained reconstruction method, is utilized to reconstruct images for each individual cardiac phase. The objective function in such a prior image constrained reconstruction method is modified to incorporate the conditions used in the production of the prior image so that the data truncation problem is properly addressed.

Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into an iterative image reconstruction process as well as utilizing an image frame from a previous time frame to constrain the reconstruction of a current image frame.

Abstract: The resolution of an image produced by a CT imaging system is increased by employing an image reconstruction method that takes advantage of the redundant attenuation measurements made during a typical scan. An initial image is reconstructed with a filtered backprojection technique using the projection views acquired during the scan. Further images of higher resolution are produced by an iterative process in which the reconstructed image is reprojected, combined with originally acquired projection data, and backprojected again at the higher resolution.

Abstract: An image reconstruction method applicable to a number of different imaging modalities including magnetic resonance imaging (MRI), x-ray computed tomography (CT), positron emission tomography (PET), and single photon emission computed tomography (SPECT) is disclosed. A sparsifying image is reconstructed from a series of acquired undersampled data to provide a priori knowledge of a subject being imaged. An iterative reconstruction process is further employed to iteratively determine a correction image for a given image frame that, when subtracted from the sparsifying image, produces a quality image for the image frame.

Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into the image reconstruction process. Thus, one aspect of the present invention is to provide an image reconstruction method that requires less number of data samples to reconstruct an accurate reconstruction of a desired image than previous methods, such as, compressed sensing. Another aspect of the invention is to provide an image reconstruction method that produces a time series of desired images indicative of a higher temporal resolution than is ordinarily achievable with the imaging system. For example, cardiac phase images can be produced with high temporal resolution (e.g., 20 milliseconds) using a CT imaging system with a slow gantry rotation speed.

Abstract: A method for reconstructing a high quality image from undersampled image data is provided. The image reconstruction method is applicable to a number of different imaging modalities. Specifically, the present invention provides an image reconstruction method that incorporates an appropriate prior image into the image reconstruction process. Thus, one aspect of the present invention is to provide an image reconstruction method that requires less number of data samples to reconstruct an accurate reconstruction of a desired image than previous methods, such as, compressed sensing. Another aspect of the invention is to provide an image reconstruction method that imparts the signal-to-noise ratio of a prior image to the desired image being reconstructed. Another aspect of the invention is to provide an image reconstruction method that, when practiced in the field of x-ray imaging, allows for exposing a subject to substantially less radiation dose than is required in conventional x-ray imaging techniques.