Tomographic image reconstruction method and apparatus using filtered back projection
AssigneeSiemens Aktiengesellschaft
InventorsJasmina Ludwig, Thomas Mertelmeier
Life of this patent
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Abstract
In a tomographical image reconstruction method and apparatus to generate an image of an examination subject from a number of digital projection data acquired at different projection angles, a first analytical filter kernel (formed by a first analytical function) is determined for a filtered back projection in the spatial frequency range, this first analytical filter kernel approximating, at least in a range of the spatial frequency, a discrete filter kernel iteratively determined for a model. Back projection is implemented with a second analytical filter kernel calculated from the analytical filter kernel and formed by a second analytical function.
Claims10
A tomographical image reconstruction method for reconstructing an image of a subject from a plurality of sets of digital projection data respectively acquired from the subject at different projection angles in an angle range, said method comprising the steps of:
- in a processor, forming a first analytical filter kernel using a first analytical function, for a filtered back projection in a spatial frequency domain, that approximates, at least in a frequency range of said spatial frequency domain, a discrete filter kernel iteratively determined for a model;
- and
- from said sets of digital projection data, reconstructing an image of the subject by filtered back projection operating on said sets of digital projection data with said first analytical filter kernel and with a second analytical filter kernel calculated from said first analytical filter kernel and formed by a second analytical function, to obtain a set of image data representing the reconstructed image of the subject.
A tomographical image reconstruction device for reconstructing an image of a subject from a plurality of sets of digital projection data respectively acquired from the subject at different projection angles in an angle range, said device comprising:
- a processor configured to form a first analytical filter kernel using a first analytical function, for a filtered back projection in a spatial frequency domain, that approximates, at least in a frequency range of said spatial frequency domain, a discrete filter kernel iteratively determined for a model;
- and
- said processor being configured to reconstruct, from said sets of digital projection data, an image of the subject by filtered back projection operating on said sets of digital projection data with said first analytical filter kernel and with a second analytical filter kernel calculated from said first analytical filter kernel and formed by a second analytical function, to obtain a set of image data representing the reconstructed image of the subject.
Dependencies are inferred from the claim text.