Results 11 to 20 of about 78,948 (263)
Remote Sensing, 2023 For triple-frequency radar, the attenuation attributed to atmospheric gases and stratiform clouds is diverse due to different snowfall microphysical properties, particularly in regions far from the radar.
Yue Chang +6 more
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An artefact of PET attenuation correction caused by iron overload of the liver in clinical PET-MRI
European Journal of Hybrid Imaging, 2017 Background Attenuation correction is one of the most important steps in producing quantitative PET image data. In hybrid PET-MRI systems, this correction is far from trivial, as MRI data are not correlated to PET attenuation properties of the scanned ...
Florian Büther +4 more
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Diagnostics, 2023 (1) Background: The CT-based attenuation correction of SPECT images is essential for obtaining accurate quantitative images in cardiovascular imaging.
Mariana Andrea Prieto Canalejo +5 more
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Attenuation correction in SPECT without attenuation map [PDF]
2011 IEEE Nuclear Science Symposium Conference Record, 2011 A method of attenuation correction in Single Photon Emission Computed Tomography (SPECT), based on emission data only is presented. The algorithm uses the well known Helgason-Ludwig consistency conditions. However, it does not attempt to find the attenuation map, but rather the correction factors for the projection data, which makes the problem simpler
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Multiview Attenuation Estimation and Correction [PDF]
Journal of Mathematical Imaging and Vision, 2019 Measuring attenuation coefficients is a fundamental problem that can be solved with diverse techniques such as X-ray or optical tomography and lidar. We propose a novel approach based on the observation of a sample from a few different angles. This principle can be used in existing devices such as lidar or various types of fluorescence microscopes.
Debarnot, Valentin +2 more
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Comparison of non-attenuation corrected and attenuation corrected myocardial perfusion SPECT
The Egyptian Journal of Radiology and Nuclear Medicine, 2016 AbstractPurposeTo assess the significance of attenuation correction on sensitivity, specificity and diagnostic accuracy of myocardial perfusion SPECT.Methods102 patients referred for myocardial perfusion imaging (MPI) were divided into two groups: 42 patients (mean age: 54.6±12.6) were enrolled in the group A, who had undergone coronary artery ...
Hasan Raza +7 more
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Regional Attenuation Correction of Weather Radar Using a Distributed Microwave-Links Network
Advances in Meteorology, 2017 The complex temporal-spatial variation of raindrop size distribution will affect the precision of precipitation quantitative estimates (QPE) produced from radar data, making it difficult to correct echo attenuation.
Yang Xue +4 more
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Magnetic Resonace–Based Attenuation Correction for Micro–Single-Photon Emission Computed Tomography
Molecular Imaging, 2012 Attenuation correction is necessary for quantification in micro–single-photon emission computed tomography (micro-SPECT). In general, this is done based on micro–computed tomographic (micro-CT) images.
Vincent Keereman +4 more
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Applied Sciences, 2022 We studied whether TOF reduces error propagation from attenuation correction to PET image reconstruction in PET/MR neuroimaging, by using imperfect attenuation maps in a clinical PET/MR system with 525 ps timing resolution. Ten subjects who had undergone
Jani Lindén +3 more
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Geomatics, Natural Hazards & Risk, 2016 Rainfall-induced attenuation is a major source of underestimation for radar-based precipitation estimation at C-band. Unconstrained gate-by-gate correction procedures are known to be inherently unstable and thus not suited for unsupervised attenuation ...
Stephan Jacobi, Maik Heistermann
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