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http://dx.doi.org/10.7742/jksr.2022.16.6.771

Noise Measurement by Percentage of Effective Linear Attenuation Coefficient of Water in CT Image of AAPM CT Performance Phantom  

Jong-Eon, Kim (Department of Radiological Science, Kaya University)
Sang-Hun, Lee (Department of Radiological Science, Kaya University)
Publication Information
Journal of the Korean Society of Radiology / v.16, no.6, 2022 , pp. 771-778 More about this Journal
Abstract
The purpose of this study is to present a method of measuring noise by the percentage of effective line attenuation coefficient of water that can be used for quality control of CT image noise using AAPM CT performance phantom in clinical practice. In the CT images obtained by scanning the AAPM CT performance phantom with a 120 kVp CT X-ray beam, the mean CT number was measured for each pin and water in the CT number linearity insert part. The effective energy was determined as the photon energy with the largest correlation coefficient from the correlation coefficients of the linear regression analysis of the measured mean CT number for each pin and water and the linear attenuation coefficient for each photon energy. And for water and acrylic, the contrast scale was calculated as 0.000188 cm-1 · HU-1 from the measured mean CT number and effective line attenuation coefficient. Using the calculated contrast scale, the effective line attenuation coefficient of water, and the standard deviation measured in the water of the alignment pin part of the AAPM CT performance phantom, The noise measurement value by the percentage of effective line attenuation coefficient of water obtained 0.31 ~ 0.52% in the range of 100 ~ 300 mAs.
Keywords
Noise; CT number; Linear attenuation coefficient; Correlation coefficient; Linearity;
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Times Cited By KSCI : 3  (Citation Analysis)
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