A Convergence Study on Evaluation of Usefulness of Copper Additional Filter in the Digital Radiography System

디지털 방사선장치에서 구리 부가필터의 유용성 평가에 관한 융복합 연구

  • Kim, Sang-Hyun (Dept. of Radiology, Seoul National University Hospital, Dept. of Radiological Science, Eulji University)
  • 김상현 (서울대학교병원 영상의학과, 을지대학교 방사선학과)
  • Received : 2015.07.23
  • Accepted : 2015.09.20
  • Published : 2015.09.28


This convergence study analyzed the effectiveness of digital radiography system of copper(Cu) filter in the added filtration for the removal of lower energy radiation through dose and image evaluation. We were analyzed from April to June 2015 result of the examination. Cu filter was applied to each non, 0.1, 0.2, 0.3 mm according to change of kV and mAs and doses were evaluated. Image quality was evaluated by PSNR, MAE, MSE, CNR, SNR and qualitative analysis was performed by seven items for resolution and contrast from chest x-ray criteria of national cancer checkup. The absorbed doses with Cu were lowered by 16-88 % than non-filter but the gaps decreased as kV increased. PSNR were over 30 dB and all significant and CNR and SNR were superior with non-filter but in the qualitative analysis, there were different statistical significant according to each item. The score of 0.1 mm filter was high at pulmonary blood vessel observation and in the 0.3 mm Cu, there were no statistical signigicant except high density and full of air portion. Cu filter can improve image quality with lower radiation dose using better radiation quality and correction power at digital radiography system.


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