Since no data is available outside the ROI, the reconstruction suffers severe artifacts often rendering the image useless.
To overcome this problem, the area outside the ROI may be blocked by using an x-ray opaque material like lead, reducing the integral dose considerably. But to achieve high resolution in the reconstruction, the dose required for imaging is very high. CT using an ROI filter provides a way to reconstruct an ROI with reduced integral dose and yet with minimal artifacts and improved spatial resolution.ĭevelopment of high-resolution detectors for Computed Tomography (CT) reconstruction has enabled reconstruction resolution on the order of tens of microns, thus enabling reconstruction of small structures like the cochlea in the inner ear, a stent deployed in a vessel 1, etc. We found that the intensity of the artifacts increases with the contrast of the object, its size, and its distance from the axis of rotation. The effect of the presence of a high contrast object outside the ROI was also studied. For an ROI of 10% FOV, artifacts remained minimal only for the 1/16 th dose case. For an ROI of 30% FOV, artifacts in the reconstructed ROI were minimal for both dose reduction levels. ROIs in the images were selected and the low-dose data outside the ROI were simulated by adding various levels of noise to the projection data corresponding to a dose of 1/16 and 1/256 of the original dose. High-resolution, high-dose full-field projections of a phantom were obtained. To obtain high-resolution 3D reconstruction of an ROI with minimal artifacts, we have developed a method involving a non-uniform ROI beam filter to reduce dose outside the ROI while acquiring the ROI at a higher dose.
#ARTIFACT MEANING FULL#
Send us feedback.High-resolution computed tomography (CT) reconstructions currently require either full field of view (FOV) exposure, resulting in high dose, or region of interest (ROI) exposure, resulting in artifacts. These example sentences are selected automatically from various online news sources to reflect current usage of the word 'artifact.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. 2022 Many of the images come from UA’s annual and sadly now-defunct Corolla yearbook, a wonderful artifact documenting the school’s rich history for decades.īen Flanagan | al, 10 Aug.
2022 It was known that Porsche-part of Volkswagen Group-needed to unload Bugatti, a costly artifact of chairman Ferdinand Piëch’s reign, which ended in 2015.ĭan Neil, WSJ, 26 Aug. 2022 Federal agents in Memphis have seized a potentially 3,000-year-old ancient Egyptian artifact that was shipped in from Europe.Īncient Egypt, Fox News, 27 Aug. 2022 On August 17, the United States Customs and Border Patrol seized a 3,000-year-old Egyptian artifact in Memphis.Įlla Feldman, Smithsonian Magazine, 31 Aug. 2022 In daylight, the band shell for which the venue is named seems like a mysterious artifact washed ashore from San Diego Bay.ĭirk Sutro, San Diego Union-Tribune, 11 Sep.
2022 If his theory was correct, and Freud had worked from a key Bacon reference, that would make the painting a remarkable artifact of the artists’ relationship. 2022 More than two years later, Eleven has returned to firing on all cylinders, but a pandemic artifact remains: the majority of employees embrace remote work.
Marisa Lascala, Good Housekeeping, 27 Sep. Recent Examples on the Web There, a young Max Mercer (Archie Yates from Jojo Rabbit) has to defend his home against a couple looking to retrieve a priceless artifact while his family is in Japan.
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