摘要:
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.
摘要:
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.
摘要:
An adaptive CT data acquisition system and technique is presented whereby radiation emitted for CT data acquisition is dynamically controlled to limit exposure to those detectors of a CT detector assembly that may be particularly susceptible to saturation during a given data acquisition. The data acquisition technique recognizes that for a given subject size and position that pre-subject filtering and collimating of a radiation beam may be insufficient to completely prevent detector saturation. Therefore, the present invention includes implementation of a number of CT data correction techniques for correcting otherwise unusable data of a saturated CT detector. These data correction techniques include a nearest neighbor correction, off-centered phantom correction, off-centered synthetic data correction, scout data correction, planar radiogram correction, and a number of others. The invention is applicable with energy discriminating CT systems as well as with conventional CT systems and other multi-energy CT systems, such as dual kVp-based systems.
摘要:
A method and apparatus for processing raw image data to create processed images. Raw image data is acquired. The raw image data is decomposed by a data decomposer into N subsets of raw image data. The number N is based on a number of available image generation processors. The N subsets of raw image data are processed by at least one image generation processor to create processed image data. If more than one image generation processor is available, the image generation processors perform image processing on the raw image data in parallel with respect to each other.
摘要:
An adaptive CT data acquisition system and technique is presented whereby radiation emitted for CT data acquisition is dynamically controlled to limit exposure to those detectors of a CT detector assembly that may be particularly susceptible to saturation during a given data acquisition. The data acquisition technique recognizes that for a given subject size and position that pre-subject filtering and collimating of a radiation beam may be insufficient to completely prevent detector saturation. Therefore, the present invention includes implementation of a number of CT data correction techniques for correcting otherwise unusable data of a saturated CT detector. These data correction techniques include a nearest neighbor correction, off-centered phantom correction, off-centered synthetic data correction, scout data correction, planar radiogram correction, and a number of others. The invention is applicable with energy discriminating CT systems as well as with conventional CT systems and other multi-energy CT systems, such as dual kVp-based systems.
摘要:
An adaptive CT data acquisition system and technique is presented whereby radiation emitted for CT data acquisition is dynamically controlled to limit exposure to those detectors of a CT detector assembly that may be particularly susceptible to saturation during a given data acquisition. The data acquisition technique recognizes that for a given subject size and position that pre-subject filtering and collimating of a radiation beam may be insufficient to completely prevent detector saturation. Therefore, the present invention includes implementation of a number of CT data correction techniques for correcting otherwise unusable data of a saturated CT detector. These data correction techniques include a nearest neighbor correction, off-centered phantom correction, off-centered synthetic data correction, scout data correction, planar radiogram correction, and a number of others. The invention is applicable with energy discriminating CT systems as well as with conventional CT systems and other multi-energy CT systems, such as dual kVp-based systems.
摘要:
An ultrasound system comprises a front end subsystem and a back end subsystem. The back end subsystem processes data samples representative of the echo signals from the front end subsystem. The back end subsystem includes at least one microprocessor with registers that simultaneously store at least two data samples. The microprocessor performs parallel common arithmetic or logic instructions upon at least two ultrasound data samples in one register. The microprocessor may be configured to scan convert polar data samples to Cartesian pixel values. During scan conversion, one register simultaneously stores multiple polar data samples and another register simultaneously stores coefficients associated with the polar data samples. The microprocessor multiplies corresponding data samples and coefficients, and sums the product of the parallel multiplication operations in order to produce a Cartesian data sample associated with a pixel to be displayed on an image arranged in a Cartesian coordinate pattern. The microprocessor may be configured to perform parallel arithmetic instructions to carry out auto-correlation operations, such as during Color Doppler signal processing. To do so, the registers store simultaneously multiple data samples representative of echo signals received from the same physical point from several transmissions. The registers each store the same data samples except that the data samples are shifted in the registers with respect to one another. During the parallel common arithmetic instructions, the microprocessor multiplies the data samples within the first and second registers and sums the products of the multiplication operations as part of an autocorrelation operation. The microprocessor may be reconfigured to perform blending operations two-dimensional greyscale images (B-mode) and Color Doppler images for a region of interest.
摘要:
A method and apparatus for providing a virtual volumetric ultrasound phantom to construct an ultrasound training system from any ultrasound system (hereafter "the ultrasound training system").The ultrasound system and method retrieve and display previously stored ultrasound data to simulate an ultrasound scanning session. A real ultrasound system acquires an image of an ultrasound phantom. The ultrasound image comprises ultrasound echo data for an image/scan plane representing a cross-section or partial volume of the ultrasound phantom. The ultrasound image is analyzed to identify image attributes that are unique for each image/scan plane. A portion of the previously stored data that corresponds to the image attributes is retrieved and displayed. In one embodiment, actual position and orientation of the acquired image/scan plane with respect to a known structure within the ultrasound phantom are determined by processing the image/scan plane to obtain a number of geometrical image parameters. Position and orientation of the image/scan plane are calculated from the image parameters using formulas based on a known three dimensional structure within the phantom. The determination of actual image/scan plane position and orientation may be enhanced using image de-correlation techniques. Retrieval of the stored data may be based upon the calculated position and orientation or on the obtained image parameters. In another embodiment of the present invention, relative changes in image/scan plane position and orientation with respect to an initial reference position and orientation are determined by processing successive acquired ultrasound images using image de-correlation techniques. In another embodiment of the present invention, the identity of each pixel or voxel within the image/scan plane is determined and a set of corresponding pixels or voxels of stored data are retrieved for display.
摘要:
A method and apparatus for processing raw image data to create processed images. Raw image data is acquired. The raw image data is decomposed by a data decomposer into N subsets of raw image data. The number N is based on a number of available image generation processors. The N subsets of raw image data are processed by at least one image generation processor to create processed image data. If more than one image generation processor is available, the image generation processors perform image processing on the raw image data in parallel with respect to each other.
摘要:
An adaptive CT data acquisition system and technique is presented whereby radiation emitted for CT data acquisition is dynamically controlled to limit exposure to those detectors of a CT detector assembly that may be particularly susceptible to saturation during a given data acquisition. The data acquisition technique recognizes that for a given subject size and position that pre-subject filtering and collimating of a radiation beam may be insufficient to completely prevent detector saturation. Therefore, the present invention includes implementation of a number of CT data correction techniques for correcting otherwise unusable data of a saturated CT detector. These data correction techniques include a nearest neighbor correction, off-centered phantom correction, off-centered synthetic data correction, scout data correction, planar radiogram correction, and a number of others. The invention is applicable with energy discriminating CT systems as well as with conventional CT systems and other multi-energy CT systems, such as dual kVp-based systems.