Imaging Science in Dentistry

Korean Academy of Oral and Maxillofacial Radiology (대한영상치의학회)
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The effects of digital image processing for noise reduction on observer performance

노이즈 감소 필터 사용이 판독능에 미치는 효과

  • Jung, Young-Chul (School of Dentistry, Seoul National University) ;
  • Choi, Bo-Ram (Department of Oral and Maxillofacial Radiology and Dental Research Institute, School of Dentistry, Seoul National University) ;
  • Huh, Kyung-Hoi (Department of Oral and Maxillofacial Radiology and Dental Research Institute, School of Dentistry, Seoul National University) ;
  • Yi, Yon-Jin (Department of Oral and Maxillofacial Radiology, Dental Research Institute, and BK21 Craniomaxillofacial Life Science, School of Dentistry, Seoul National University) ;
  • Heo, Min-Suk (Department of Oral and Maxillofacial Radiology and Dental Research Institute, School of Dentistry, Seoul National University) ;
  • Lee, Sam-Sun (Department of Oral and Maxillofacial Radiology, Dental Research Institute, and BK21 Craniomaxillofacial Life Science, School of Dentistry, Seoul National University) ;
  • Choi, Soon-Chul (Department of Oral and Maxillofacial Radiology and Dental Research Institute, School of Dentistry, Seoul National University)
  • 정영철 (서울대학교 치의학대학원) ;
  • 최보람 (서울대학교 치의학대학원 구강악안면방사선학교실) ;
  • 허경회 (서울대학교 치의학대학원 구강악안면방사선학교실) ;
  • 이원진 (서울대학교 치의학대학원 구강악안면방사선학교실, 치학연구소 및 BK21 치의학생명과학사업단) ;
  • 허민석 (서울대학교 치의학대학원 구강악안면방사선학교실) ;
  • 이삼선 (서울대학교 치의학대학원 구강악안면방사선학교실, 치학연구소 및 BK21 치의학생명과학사업단) ;
  • 최순철 (서울대학교 치의학대학원 구강악안면방사선학교실)
  • Received : 2010.04.21
  • Accepted : 2010.06.07
  • Published : 2010.09.30
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Abstract

Purpose : This study was performed to examine the effects of image filter on observer performance by counting the number of holes at each wedge step on a radiographic image. Materials and Methods : An aluminum step wedge with 11 steps ranged in thickness from 1.5 mm to 16.5 mm in 1.5 mm increments was fabricated for this study. Each step had 10 notched holes with 1.0 mm diameter on the bottom of the step wedge which were ranged in depths from 0.1 mm to 1.0 mm in 0.1 mm increments. Digital radiographic raw images of the aluminum step wedge were acquired by using CCD intraoral sensor. The images were processed using several types of noise reduction filters and kernel sizes. Three observers counted the number of holes which could be discriminated on each step. The data were analyzed by ANOVA. Results : The number of holes at each step was decreased as the thickness of step was increased. The number of holes at each step on the raw images was significantly higher than that on the processed images. The number of holes was different according to the types and kernel sizes of the image filters. Conclusions : The types and kernel sizes of image filters on observer performance were important, therefore, they should be standardized for commercial digital imaging systems.

Keywords

References

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