摘要:
A system and method for ascertaining the identity of an object within an enclosed article. The system includes an acquisition subsystem, a reconstruction subsystem, a computer-aided detection (CAD) subsystem, and an alarm resolution subsystem. The acquisition subsystem communicates view data to the reconstruction subsystem, which reconstructs it into image data and communicates it to the CAD subsystem. The CAD subsystem analyzes the image data to ascertain whether it contains any area of interest. A feedback loop between the reconstruction and CAD subsystems allows for continued, more extensive analysis of the object. Other information, such as risk variables or trace chemical detection information may be communicated to the CAD subsystem to dynamically adjust the computational load of the analysis.
摘要:
A system and method for ascertaining the identity of an object within an enclosed article. The system includes an acquisition subsystem utilizing a stationary radiation source and detector, a reconstruction subsystem, a computer-aided detection (CAD) subsystem, and a 2D/3D visualization subsystem. The detector may be an energy discriminating detector. The acquisition subsystem communicates view data to the reconstruction subsystem, which reconstructs it into image data and communicates it to the CAD subsystem. The CAD subsystem analyzes the image data to ascertain whether it contains any area of interest. Any such area of interest data is sent to the reconstruction subsystem for further reconstruction, using more rigorous algorithms and further analyzed by the CAD subsystem. Other information, such as risk variables or trace chemical detection information may be communicated to the CAD subsystem to be included in its analysis.
摘要:
A technique is disclosed for detecting contraband by obtaining image data from a computed tomography machine and generating variance data and a variance map from the image data acquired. The method includes obtaining a mean density value and a variation value for each voxel of the image data, segmenting the voxels into discrete objects, and determining whether any of the discrete objects is contraband.
摘要:
A technique is disclosed for generating variance data and a variance map from measured projection data acquired from a tomography system. The method comprises accessing the measured projection data from the tomography system. The method further comprises generating the variance map from the measured projection data and displaying, analyzing or processing the variance map. The variance data is determined based upon a statistical model from measured image data, and may be used for image analysis, data acquisition, in computer aided diagnosis routines, and so forth.
摘要:
Methods and systems for controlling x-ray exposure during a dynamic pitch helical scan using a translatable table are provided. The system includes a collimator positioned between an x-ray source and an object to be scanned configured to shutter an x-ray fan beam generated by the x-ray source to at least one of translate the x-ray fan beam along a z-axis of the scan and vary the width of the x-ray beam along the z-axis, and a collimator controller configured to dynamically position the collimator using at least one of predetermined trajectory of the translatable table and a current position of the translatable table.
摘要:
A method for reconstructing image data from acquired tomographic projection data measurements is provided. The projection data measurements comprise one or more missing data measurements. The method comprises generating a coarse-resolution projection data set from the acquired projection data measurements and performing an iterative reconstruction on the coarse-resolution projection data set to generate a coarse-resolution reconstructed data set. Then, the method comprises reprojecting the coarse-resolution reconstructed data set to obtain one or more estimates for the one or more missing data measurements. The one or more estimated missing data measurements are then recombined with the acquired projection data measurements, to generate a recombined data set. Then, a direct reconstruction algorithm is applied to the recombined data set to generate the reconstructed image data.
摘要:
A technique is provided for improving z-axis coverage and/or reducing cone beam artifacts during CT imaging. Multiple X-ray emission points are provided along the z-axis. Some or all of the emission points may be concurrently active. X-rays from concurrently active emission points are collimated so that X-rays from two or more emission points do not overlap on the detector. In addition, different groups of concurrently activated emission points may be sequentially or alternately activated, in conjunction with collimation, to prevent the overlap of X-rays from different emission points on the detector. In this manner, The X-rays may be timed and collimated such that the respective streams of radiation become adjacent at different locations, such as at the detector, the isocenter, or edge of the field of view.
摘要:
Configurations for stationary imaging systems are provided. The configurations may include combinations of various types of distributed sources of X-ray radiation, which generally include addressable emitter elements which may be triggered for emission in desired sequences and combinations. The sources may be ring-like, partial ring-like, or line-like (typically along a Z-axis), and so forth. Combinations of these are envisaged. Corresponding detectors may also be full ring detectors or partial ring detectors associated with the sources to provide sufficient coverage of imaging volumes and to provide the desired mathematical completeness of the collected data.
摘要:
A method for imaging an object is provided. The method includes acquiring image data of the object, wherein the image data includes a plurality of original voxels, and identifying, using a processing device, a first subset of voxels from the acquired image data. The method also includes performing a principal component analysis (PCA) on the first subset of voxels and determining whether sheet-like material is present in the object based on the results of the performed PCA on the first subset of voxels.
摘要:
A method for imaging an object is provided. The method includes acquiring image data of the object, wherein the image data includes a plurality of original voxels, and identifying, using a processing device, a first subset of voxels from the acquired image data. The method also includes performing a principal component analysis (PCA) on the first subset of voxels and determining whether sheet-like material is present in the object based on the results of the performed PCA on the first subset of voxels.