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http://dx.doi.org/10.7742/jksr.2021.15.2.125

Measurement of CT Numbers for Effective Atomic Number And Physical Density of Compound  

Kim, Jong Eon (Department of Radiological Science, Kaya University)
Publication Information
Journal of the Korean Society of Radiology / v.15, no.2, 2021 , pp. 125-130 More about this Journal
Abstract
In the AAPM CT performance phantom, there is little data on the CT number of the effective atomic number and physical density corresponding to each peg and water of the CT number calibration insert. Therefore, the necessity of documentation was raised.The purpose of this study is to calculate the effective atomic number for each peg and water of the CT number calibration insert in the AAPM CT performance phantom, and to measure the CT number for the calculated effective atomic number and physical density for comparative analysis.In order to obtain CT number data on the effective atomic number and physical density of each peg and water from the CT number calibration insert of the AAPM CT performance phantom, the effective atomic number for each peg and water was first calculated. Then, CT slices were obtained by scanning the CT number calibration with a CT scanner. CT numbers were measured for each peg and water in the central CT slice. As a result, the CT numbers for the effective atomic number showed a nonlinear pattern of repeating the increase and decrease as the effective atomic number increased. In addition, the CT numbers for physical density showed a nonlinear pattern of repeating the increase and decrease as the physical density increased.
Keywords
CT number; AAPM CT performance phantom; Effective atomic number; Physical density;
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