title: Quality assurance: using the exposure index and the deviation index to monitor radiation exposure for portable chest radiographs in neonates.
abstract: BACKGROUND
  Many methods are used to track patient exposure during acquisition of plain film radiographs. A uniform international standard would aid this process.
  
  
  OBJECTIVE
  To evaluate and describe a new, simple quality-assurance method for monitoring patient exposure. This method uses the "exposure index" and the "deviation index," recently developed by the International Electrotechnical Commission (IEC) and American Association of Physicists in Medicine (AAPM). The deviation index measures variation from an ideal target exposure index value. Our objective was to determine whether the exposure index and the deviation index can be used to monitor and control exposure drift over time.
  
  
  METHODS
  Our Agfa workstation automatically keeps a record of the exposure index for every patient. The exposure index and deviation index were calculated on 1,884 consecutive neonatal chest images. Exposure of a neonatal chest phantom was performed as a control.
  
  
  RESULTS
  Acquisition of the exposure index and calculation of the deviation index was easily achieved. The weekly mean exposure index of the phantom and the patients was stable and showed <10% change during the study, indicating no exposure drift during the study period.
  
  
  CONCLUSIONS
  The exposure index is an excellent tool to monitor the consistency of patient exposures. It does not indicate the exposure value used, but is an index to track compliance with a pre-determined target exposure.
authors.affiliation: Department of Radiology, Riley Children's Hospital, Indiana University School of Medicine, Indianapolis, IN, USA. mecohen@iupui.edu
authors.forename: Mervyn D
authors.initials: MD
authors.lastname: Cohen
authors.forename: Matt L
authors.initials: ML
authors.lastname: Cooper
authors.forename: Kelly
authors.initials: K
authors.lastname: Piersall
authors.forename: Bruce K
authors.initials: BK
authors.lastname: Apgar
mesh_terms: D001822:Body Burden; D006801:Humans; D007231:Infant, Newborn; D019047:Phantoms, Imaging; D011785:Quality Assurance, Health Care; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement; D013902:Radiography, Thoracic; D011874:Radiometry / Q000592:standards*; D012042:Registries; D018709:Statistics, Nonparametric