title: Optimisation of radiological protocols for chest imaging using computed radiography and flat-panel X-ray detectors.
abstract: OBJECTIVE
  Digital radiography technology has replaced conventional screen-film systems in many hospitals. Despite the different characteristics of new detector materials, frequently, the same radiological protocols previously optimised for screen film are still used with digital equipment without any critical review. This study addressed optimisation of exposure settings for chest examinations with digital systems, considering both image quality and patient dose.
  
  
  METHODS
  Images acquired with direct digital radiography equipment and a computed radiography system were analysed with specially developed commercial software with a four-alternative forced-choice method: the most promising protocols were then scored by two senior radiologists.
  
  
  RESULTS
  Digital technology offers a wide dynamic range and the ability to postprocess images, allowing use of lower tube potentials in chest examinations. The computed radiography system showed both better image quality and lower dose at lower energies (85 kVp and 95 kVp) than those currently used (125 kVp). Direct digital radiography equipment confirmed both its superior image quality and lower dose requirements compared with the storage phosphor plate system.
  
  
  CONCLUSIONS
  Generally, lowering tube potentials in chest examinations seems to allow better image quality/effective dose ratio when using digital equipment.
authors.affiliation: UO Fisica Sanitaria, Policlinico S Orsola Malpighi, Azienda Ospedaliero Universitaria di Bologna, Via Massarenti 9, 40138 Bologna, Italy. gaetano.compagnone@aosp.bo.it
authors.forename: G
authors.initials: G
authors.lastname: Compagnone
authors.forename: M
authors.initials: M
authors.lastname: Casadio Baleni
authors.forename: E
authors.initials: E
authors.lastname: Di Nicola
authors.forename: M
authors.initials: M
authors.lastname: Valentino
authors.forename: M
authors.initials: M
authors.lastname: Benati
authors.forename: L F
authors.initials: LF
authors.lastname: Calzolaio
authors.forename: N
authors.initials: N
authors.lastname: Oberhofer
authors.forename: E
authors.initials: E
authors.lastname: Fabbri
authors.forename: S
authors.initials: S
authors.lastname: Domenichelli
authors.forename: L
authors.initials: L
authors.lastname: Barozzi
mesh_terms: D002985:Clinical Protocols / Q000592:standards*; D004867:Equipment Design; D006801:Humans; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement / Q000295:instrumentation / Q000592:standards*; D011857:Radiographic Image Interpretation, Computer-Assisted; D013902:Radiography, Thoracic / Q000295:instrumentation / Q000592:standards*; D015203:Reproducibility of Results; D012984:Software; D014057:Tomography, X-Ray Computed / Q000592:standards*; D014963:X-Ray Intensifying Screens