A Constancy Study for Quality Control of Digital radiographic Images Jeung Seung-Hun1, Lim Cheong-Hwan2 1Dept. of Health Care, Hanseo University, 46. Hanseo 1-ro, Haemi-Myun, Seosan-Si, Chungcheognamdo 2Dept. of Radiological Science, Hanseo University, 46. Hanseo 1-ro, Haemi-Myun, Seosan-Si, Chungcheognam-do, 31962, Republic of Korea Online published on 14 May, 2018. Abstract The International Electro technical Commission (IEC) recommends quality control of images such as the Constancy Test and the detective quantum efficiency (DQE) for digital radiography quality control. However, this kind of image quality control has not been implemented in Korean digital radiography. In this study, constancy tests that are usually not conducted in Korea were performed and related items assessed. Based on the constancy tests measured values after three weeks and three months, the evaluation items were the signal-noise ratio(SNR), the contrast, the Modulation Transfer Function (MTF), the Noise-Power Spectrum (NPS), and the relative DQE. The reference values of the diagnostic radiation generation this study, were a contrast of 0.12 and a SNR of 4.02: Furthermore, the information transfer ability was 94% at 1.0lp/mm, 83% at 2.0lp/mm, and 73% at 3.0lp/mm. The MTF of 10% was 8.6lp/mm, the MTF of 50% was 4.6lp/mm, and the NPS 5.1 at 1.0lp/mm, 4.4 at 2.0lp/mm, and 3.5 at 3.0lp/mm. The relative DQE was 1.49 for 1.0lp/mm, 1.4 for 2.0lp/mm, and 1.3 for 3.0lp/mm. All measures decreased with time, based on Constancy Test. If currently implemented safety management items are reflected in the safety management evaluation radiation-generating devices change to digital versions, they will be of great help in the quality control of radiographic images. Top Keywords Digital Radiography, Computed Radiography, Modulation Transfer Function, Detective Quantum Efficiency, Signal to Noise Ratio, Density. Top |