Artifacts in CT: Recognition and Avoidance

Abstract

Artifacts can seriously degrade the quality of computed tomographic (CT) images, sometimes to the point of making them diagnostically unusable. To optimize image quality, it is necessary to understand why artifacts occur and how they can be prevented or suppressed. CT artifacts originate from a range of sources. Physics-based artifacts result from the physical processes involved in the acquisition of CT data. Patient-based artifacts are caused by such factors as patient movement or the presence of metallic materials in or on the patient. Scanner-based artifacts result from imperfections in scanner function. Helical and multisection technique artifacts are produced by the image reconstruction process. Design features incorporated into modern CT scanners minimize some types of artifacts, and some can be partially corrected by the scanner software. However, in many instances, careful patient positioning and optimum selection of scanning parameters are the most important factors in avoiding CT artifacts.

A comparative study on interpolation methods for controlled cardiac CT

“…The ring artifact was apparent in images reconstructed using parallel-beam/t-FDK reconstruction algorithm after nearest neighbor interpolation was used. Ring artifact is explained in (Barret and Keat, 2004).…”

A comparison of multi-scale 3D X-ray tomographic inspection techniques for assessing carbon fibre composite impact damage

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