title: Investigating the use of an antiscatter grid in chest radiography for average adults with a computed radiography imaging system.
abstract: OBJECTIVE
  The aim of this study was to investigate via simulation a proposed change to clinical practice for chest radiography. The validity of using a scatter rejection grid across the diagnostic energy range (60-125 kVp), in conjunction with appropriate tube current-time product (mAs) for imaging with a computed radiography (CR) system was investigated.
  
  
  METHODS
  A digitally reconstructed radiograph algorithm was used, which was capable of simulating CR chest radiographs with various tube voltages, receptor doses and scatter rejection methods. Four experienced image evaluators graded images with a grid (n = 80) at tube voltages across the diagnostic energy range and varying detector air kermas. These were scored against corresponding images reconstructed without a grid, as per current clinical protocol.
  
  
  RESULTS
  For all patients, diagnostic image quality improved with the use of a grid, without the need to increase tube mAs (and therefore patient dose), irrespective of the tube voltage used. Increasing tube mAs by an amount determined by the Bucky factor made little difference to image quality.
  
  
  CONCLUSIONS
  A virtual clinical trial has been performed with simulated chest CR images. RESULTS indicate that the use of a grid improves diagnostic image quality for average adults, without the need to increase tube mAs, even at low tube voltages.
  
  
  CONCLUSIONS
  Validated with images containing realistic anatomical noise, it is possible to improve image quality by utilizing grids for chest radiography with CR systems without increasing patient exposure. Increasing tube mAs by an amount determined by the Bucky factor is not justified.
authors.affiliation: 1 Radiation Physics Department, Queen's Centre for Oncology and Haematology, Castle Hill Hospital, Hull and East Yorkshire Hospitals NHS Trust, Hull, UK.
authors.forename: C S
authors.initials: CS
authors.lastname: Moore
authors.forename: T J
authors.initials: TJ
authors.lastname: Wood
authors.forename: G
authors.initials: G
authors.lastname: Avery
authors.forename: S
authors.initials: S
authors.lastname: Balcam
authors.forename: L
authors.initials: L
authors.lastname: Needler
authors.forename: A
authors.initials: A
authors.lastname: Smith
authors.forename: J R
authors.initials: JR
authors.lastname: Saunderson
authors.forename: A W
authors.initials: AW
authors.lastname: Beavis
mesh_terms: D000328:Adult; D000465:Algorithms; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D013902:Radiography, Thoracic / Q000379:methods*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*; D014584:User-Computer Interface