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PubMed · 17082702

Computer-simulation technique for low dose computed tomographic screening.

Kouzou Hanai·Tetsuya Horiuchi·Junko Sekiguchi·Yoshihisa Muramatsu·Ryutaro Kakinuma·Noriyuki Moriyama·Ryosuke Tuchiiya·Noboru Niki
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Abstract

OBJECTIVES: The purpose of this study is to assess the relative influence of noise and artifact in detecting lung nodules on low dose computed tomographic (CT) screening. METHODS: We develop the computer-simulation technique that allows tube current simulation and virtual nodule insertion in any CT images. The tube current simulation uses a reduction model that adds random Gaussian noise distribution to existing projection data. The virtual nodules are generated using a dedicated CT simulation tool with same scanner geometry. RESULTS: The coefficient of the correlations between the contrast-to-noise ratio of the actual scan and simulated tube current images was 0.98. There was no difference in CT number between virtual nodules and actual nodules [t test results = 0.60, t50(0.01) = 2.70 at 10 mA] and the coefficient of the correlations of the image noise was 0.99. CONCLUSIONS: Our technique is useful for systematic evaluation of radiation dose reduction and structure visibility in low-dose CT screening.

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Computer SimulationPhantoms, ImagingRadiation DosageTomography, X-Ray ComputedJournal ArticleResearch Support, Non-U.S. Gov't

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Kouzou Hanai, Tetsuya Horiuchi, Junko Sekiguchi, Yoshihisa Muramatsu, Ryutaro Kakinuma, Noriyuki Moriyama, Ryosuke Tuchiiya, Noboru Niki. Computer-simulation technique for low dose computed tomographic screening.. https://doi.org/10.1097/01.rct.0000230011.16468.0e

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