Learn More
In x-ray tomography, the structure of a three-dimensional body is reconstructed from a collection of projection images of the body. Medical CT imaging does this using an extensive set of projections from all around the body. However, in many practical imaging situations only a small number of truncated projections are available from a limited angle of view.(More)
The problem of reconstructing an unknown electric conductivity from boundary measurements has applications in medical imaging, geophysics, and nondestructive testing. A. Nachman [Ann. of Math. 143 (1996)] proved global uniqueness for the 2-D inverse conductivity problem using a constructive method of proof. Based on this proof, Siltanen, Mueller and(More)
A numerical method is introduced for the evaluation of complex geometrical optics (cgo) solutions to the conductivity equation ∇ · σ∇u(· , k) = 0 in R 2 for piecewise smooth conductivities σ. Here k is a complex parameter. The algorithm is based on the solution by Astala and Päivärinta [Ann. of Math. 163 (2006)] of Calderón's inverse conductivity problem(More)
The problem this paper addresses is how to use the two-dimensional D-bar method for electrical impedance tomography with experimental data collected on finitely many electrodes covering a portion of the boundary of a body. This requires an approximation of the Dirichlet-to-Neumann, or voltage-to-current density map, defined on the entire boundary of the(More)
  • Pertti Pasanen, Jari Kaipio, Docent Ville Kolehmainen, Marko Docent, Vauhkonen, David Boas +2 others
Optical tomography is a relatively new imaging modality in which images of the optical properties of the medium are estimated based on measurements of visible or near-infrared light on the surface of the object. The image reconstruction problem in optical tomography is a non-linear ill-posed inverse problem. Thus, even small errors in the measurements or(More)
In X-ray tomography, the structure of a three dimensional body is reconstructed from a collection of projection images of the body. Medical CT imaging does this using an extensive set of projections from all around the body. However, in many practical imaging situations only a small number of truncated projections is available from a limited angle of view.(More)
  • K Astala, J L Mueller, A Per¨am¨aki, L P Aiv¨arinta, S Siltanen
  • 2010
A new reconstruction algorithm is presented for eit in dimension two, based on the constructive uniqueness proof given by Astala and Päivärinta in [Ann. of Math. 163 (2006)]. The method is non-iterative, provides a noise-robust solution of the full nonlinear eit problem, and applies to more general conductivities than previous approaches. In particular, the(More)
The aim of X-ray tomography is to reconstruct an unknown physical body from a collection of projection images. When the projection images are only available from a limited angle of view, the reconstruction problem is a severely ill-posed inverse problem. Statistical inversion allows stable solution of the limited-angle tomography problem by complementing(More)
Diagnostic and operational tasks based on dental radiology often require three-dimensional (3-D) information that is not available in a single X-ray projection image. Comprehensive 3-D information about tissues can be obtained by computerized tomography (CT) imaging. However, in dental imaging a conventional CT scan may not be available or practical because(More)