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Showing 1 to 11 of 11 for “"Iterative image reconstruction."”.
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System Optimization and Iterative Image Reconstruction in Photoacoustic Computed Tomography for Breast Imaging
… tumor can be directly quantified, therefore the images produced by such optimized imaging systems are not only visually appealing, but most informative in terms of the tumor detection task. Fourth, when imaging a large three-dimensional (3D) object such as the breast, iterative reconstruction …
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A Novel Methodology for Iterative Image Reconstruction in SPECT Using Deterministic Particle Transport
… at different angles around the patient. This reconstruction can be improved by properly modeling the physics in the patient, i.e., particle absorption and scattering. Currently, such modeling is done using statistical Monte Carlo methods, but deterministic codes have the potential to offer …
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Three-Dimensional Photoacoustic Computed Tomography: Imaging Models and Reconstruction Algorithms
… of experimental designs. Meanwhile, a variety of image reconstruction algorithms have been developed for the purpose of computed tomography. Most of these algorithms assume full knowledge of the acoustic pressure function on a measurement surface that either encloses the object or extends to …
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Image Reconstruction in Photoacoustic Computed Tomography with Acoustically Heterogeneous Media
… hybrid imaging modality that combines optical image contrast with ultrasound detection. The majority of currently available PACT image reconstruction algorithms are based on idealized imaging models that assume a lossless and acoustically homogeneous medium. However, in many applications of …
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Low-dose imaging of liver diseases through neutron stimulated emission computed tomography: Simulations in GEANT4
… tomographic acquisition protocol followed by iterative image reconstruction. These studies have shown that moderate concentrations of iron can be detected in the liver with moderate dose levels and long scan times. However, a low-dose, reduced scan time technique to differentiate various liver …
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Parallel Image Reconstruction Systems for Magnetic Induction Tomography
… the resulting magnetic field perturbations. An image of conductivity distribution within the object is reconstructed by iteratively solving a non-linear inverse problem.<br/><br/>As a relatively new imaging technique, MIT encounters several challenges both in terms of the formulation of the …
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Optimizing Kilovoltage Cone-Beam Computed Tomography for Image-Guided Radiation Therapy
… (kV CBCT) has important applications in image guided radiation therapy (IGRT). In its current state, CBCT is suboptimal for these applications due to its considerable radiation dose, poor soft-tissue contrast and inaccurate Hounsfield Units as a result of in-patient scatter. The specific …
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Implementation of Iterative Reconstruction of Images from Multiple Bases Representations
Usually, image compression techniques that use only one transform exhibit some poor properties. For instance, the Discrete Cosine Transform (DCT) cannot efficiently represent high frequency components, resulting in blurred images. The Multiple Bases Representation (MBR) compression technique, which …
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Modeling and Development of Iterative Reconstruction Algorithms in Emerging X-ray Imaging Technologies
… radiation doses associated with use of analytic reconstruction methods in DPCT, we analyze the numerical and statistical properties of two classes of discrete imaging models that form the basis for iterative image reconstruction. Secondly, to improve image quality in grating-based phase-contrast …
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Dual energy image reconstruction and systems for application in proton therapy treatment planning
… makes use of CT spectra to create two sets of CT images simultaneously. DECT relies on the energy independence of relative electron density, and the energy and atomic number dependence of X-ray interaction atomic cross-sections. Post processing of the two reconstructed CT images results in two …
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Robust and efficient methods for proton computed tomography.
… have been significant improvements regarding the reconstruction of accurate RSP which makes pCT a reliable alternative to X-ray CT for planning proton therapy treatments. There are several conditions in pCT that can negatively affect the accuracy of pCT images. The goal of this dissertation is …