title: [The use of an asymmetric film-screen combination for the imaging of round pulmonary foci].
abstract: OBJECTIVE
  To examine the diagnostic advantages of an asymmetric film-screen system (a-FSS) compared to a conventional 200-speed FSS with and without anatomical lung filter.
  
  
  METHODS
  Standard radiographs were obtained from an anthropomorphic chest phantom with simulated pulmonary nodules. The existence or non-existence of nodules was assessed in 7344 individual observations. The results were evaluated using ROC analysis.
  
  
  RESULTS
  In an overall evaluation the a-FSS with an ROC area of 0.873 +/- 0.018 was not significantly superior (p > 0.05) to the lung filter but significantly superior (p < 0.05) to the 200-speed FSS. In the mediastinum the a-FSS and the lung filter were significantly superior (p < 0.05) to the 200-speed FSS. In the lung areas the 200-speed FSS and the a-FSS attained equivalent results (p > 0.05), whereas the lung filter was rated significantly lower (p < 0.05).
  
  
  CONCLUSIONS
  Asymmetric FSS improves chest diagnostics, because it yields significantly more diagnostic information in the mediastinum using equivalent x-ray exposure without reducing the image quality in the lung areas in respect of simulated pulmonary nodules.
authors.affiliation: Zentralinstitut für Röntgendiagnostik, Universitätsklinikum, GHS, Essen.
authors.forename: R D
authors.initials: RD
authors.lastname: Müller
authors.forename: S
authors.initials: S
authors.lastname: Wähling
authors.forename: H
authors.initials: H
authors.lastname: Hirche
authors.forename: M
authors.initials: M
authors.lastname: Voss
authors.forename: P
authors.initials: P
authors.lastname: Gocke
authors.forename: C
authors.initials: C
authors.lastname: Gocke
authors.forename: C
authors.initials: C
authors.lastname: Blendl
authors.forename: B
authors.initials: B
authors.lastname: Turowski
authors.forename: B
authors.initials: B
authors.lastname: Buddenbrock
authors.forename: V
authors.initials: V
authors.lastname: John
mesh_terms: D005069:Evaluation Studies as Topic; D005374:Filtration / Q000295:instrumentation; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging*; D008171:Lung Diseases / Q000000981:diagnostic imaging*; D015999:Multivariate Analysis; D015588:Observer Variation; D019047:Phantoms, Imaging / Q000706:statistics & numerical data; D012372:ROC Curve; D013902:Radiography, Thoracic / Q000295:instrumentation / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D014963:X-Ray Intensifying Screens / Q000706:statistics & numerical data
vernacular_title: Einsatz einer asymmetrischen Film-Folien-Kombination zur Abbildung pulmonaler Rundherde.