Topic
Geometric tomography
About: Geometric tomography is a research topic. Over the lifetime, 46 publications have been published within this topic receiving 1387 citations.
Papers
TL;DR: The various reconstruction algorithms used to produce tomosynthesis images, as well as approaches used to minimize the residual blur from out-of-plane structures are described.
Abstract: Digital x-ray tomosynthesis is a technique for producing slice images using conventional x-ray systems. It is a refinement of conventional geometric tomography, which has been known since the 1930s. In conventional geometric tomography, the x-ray tube and image receptor move in synchrony on opposite sides of the patient to produce a plane of structures in sharp focus at the plane containing the fulcrum of the motion; all other structures above and below the fulcrum plane are blurred and thus less visible in the resulting image. Tomosynthesis improves upon conventional geometric tomography in that it allows an arbitrary number of in-focus planes to be generated retrospectively from a sequence of projection radiographs that are acquired during a single motion of the x-ray tube. By shifting and adding these projection radiographs, specific planes may be reconstructed. This topical review describes the various reconstruction algorithms used to produce tomosynthesis images, as well as approaches used to minimize the residual blur from out-of-plane structures. Historical background and mathematical details are given for the various approaches described. Approaches for optimizing the tomosynthesis image are given. Applications of tomosynthesis to various clinical tasks, including angiography, chest imaging, mammography, dental imaging and orthopaedic imaging, are also described.
1,043 citations
135 citations
TL;DR: In this article, the chemical distribution of oxide layers around functional tungsten nanotips using electron tomography is studied, and the surface reconstruction by geometric tomography from annular dark field scanning transmission electron microscopy images can be combined with EDX tomography reconstructions to reduce backprojection artefacts and improve the sharpness of the surface contours.
Abstract: The chemical distribution of oxide layers around functional tungsten nanotips is studied using electron tomography. Three-dimensional element distribution functions are derived for such tips, giving insight into the subsurface chemistry. Energy dispersive x-ray (EDX) spectroscopy is coupled to computed tomography to reconstruct slices across the tip. It is finally shown how the surface reconstruction by geometric tomography from annular dark field scanning transmission electron microscopy images can be combined with EDX tomography reconstructions to reduce backprojection artefacts and improve the sharpness of the surface contours.
39 citations
TL;DR: Geometric tomography (GT), a technique for processing tomographic projections in order to reconstruct the external and internal boundaries of objects, is presented and it is shown that the segmentation can be performed directly with the raw data, the sinogram produced with the scanner, and that those segmented shapes can be geometrically transformed into reconstructed shapes in the usual space.
Abstract: Geometric tomography (GT), a technique for processing tomographic projections in order to reconstruct the external and internal boundaries of objects, is presented. GT does not necessitate the reconstruction of an image of the slice of the object. It is shown that the segmentation can be performed directly with the raw data, the sinogram produced with the scanner, and that those segmented shapes can be geometrically transformed into reconstructed shapes in the usual space. If one is interested in only the boundaries of the objects, they do not need to reconstruct an image, and therefore the method needs much less computation than those using traditional computed tomography techniques. Experimental results are presented for both synthesized and real data, leading to subpixel positioning of the reconstructed boundaries. GT gives its best results for sparse, highly contrasted objects such as bones or blood vessels in angiograms, it allows 'on the fly' processing of the data, and real time tracking of the object boundaries. >
33 citations
TL;DR: This work gives a special realization of the generalized conics' theory with applications in geometric tomography of subsets in the space all of whose points have the same average distance from the set of foci.
27 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 1 |
| 2019 | 1 |
| 2018 | 1 |
| 2017 | 1 |
| 2014 | 1 |