title: Digital slot-scan charge-coupled device radiography versus AMBER and Bucky screen-film radiography: comparison of image quality in a phantom study.
abstract: OBJECTIVE
  To evaluate the image quality and performance of a chest digital radiography system and to compare this with the image quality and performance of advanced multiple-beam equalization radiography (AMBER) and Bucky screen-film radiography systems.
  
  
  METHODS
  The chest digital radiography system is a digital charge-coupled device (CCD) chest imaging unit that uses slot-scan technology. A contrast-detail test object was used in combination with a phantom that simulates the primary and scatter transmission for the lungs and mediastinum. Twelve phantom images were obtained with each modality (ie, CCD digital radiography and AMBER and Bucky screen-film radiography) and were judged by six observers. CCD digital radiography soft-copy reading was compared with AMBER hard-copy reading. To measure image quality, contrast-detail curves were constructed from the observer data. The Wilcoxon signed rank test was used for statistical analysis.
  
  
  RESULTS
  For the lung configuration, contrast-detail curves showed lower threshold depth for hard-copy images obtained with CCD digital radiography than for those obtained with Bucky screen-film radiography. For hard-copy images, the difference between contrast-detail curves for CCD digital radiography and those for Bucky screen-film radiography was statistically significant (P < .006). No significant difference was found between CCD digital radiography and AMBER for hard-copy images obtained in either the lung or mediastinum configuration. For the lung configuration, a lower threshold depth was observed for CCD digital radiography soft-copy reading than for AMBER hard-copy reading, with significantly different contrast-detail curves for CCD digital radiography soft copy and AMBER hard copy (P < .006). No significant difference was found between either system for the mediastinum configuration.
  
  
  CONCLUSIONS
  Contrast-detail curves indicate that image quality for the CCD chest system provides a digital alternative to AMBER and Bucky screen-film radiography.
authors.affiliation: Department of Radiology, C2S, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands. w.j.h.veldkamp@lumc.nl
authors.forename: Wouter J H
authors.initials: WJ
authors.lastname: Veldkamp
authors.forename: Lucia J M
authors.initials: LJ
authors.lastname: Kroft
authors.forename: Bart J A
authors.initials: BJ
authors.lastname: Mertens
authors.forename: Jacob
authors.initials: J
authors.lastname: Geleijns
mesh_terms: D019047:Phantoms, Imaging; D013902:Radiography, Thoracic / Q000295:instrumentation* / Q000379:methods* / Q000592:standards; D014963:X-Ray Intensifying Screens