title: The effect of trauma backboards on computed tomography radiation dose.
abstract: OBJECTIVE
  To assess the effect of trauma backboards on the radiation dose at computed tomography (CT) when using automatic tube current modulation (ATCM).
  
  
  METHODS
  An anthropomorphic phantom was scanned with two commercially available CT systems (GE LightSpeed16 Pro and Siemens Definition AS+) without and with backboards. Tube current-time product (mAs), and CTDIvol (mGy) were recorded for each examination. Thermoluminescent dosimeters were used to measure skin entrance dose in the pelvis and breast. Statistical significance was determined using a two-sample t-test. In addition, an institutional review board-approved retrospective image review was performed to quantify the frequency of backboard use during CT in the emergency department.
  
  
  RESULTS
  There was a statistically significant increase in maximum tube current-time product (p<0.05) and CTDIvol (p<0.05) with the presence of a backboard; tube current-time product increased up to 31% and CTDIvol increased up to 27%. There was a significant increase in skin entrance dose in the anterior and posterior pelvis (p<0.05) with the presence of a backboard; skin entrance dose increased up to 25% in the anterior pelvis. Skin entrance dose to the breast increased with a backboard, although this was not statistically significant. The frequency of backboard use during CT markedly decreased (from 77% to 3%) after instituting a multidisciplinary policy to promptly remove patients from backboards upon arrival to the emergency department after a primary clinical survey.
  
  
  CONCLUSIONS
  Using backboards during CT with ATCM can significantly increase the radiation dose. Although the decision to maintain patients on backboards is multifactorial, attempts should be made to minimise backboard use during CT when possible.
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, 1600 Divisadero Street, San Francisco, CA 94115, USA.
authors.forename: A Y
authors.initials: AY
authors.lastname: Lee
authors.affiliation: Department of Radiology, University of New Mexico, MSC 10-5530, Albuquerque, NM 87131, USA.
authors.forename: S
authors.initials: S
authors.lastname: Elojeimy
authors.affiliation: Department of Radiology, University of Washington, Box 359728, 325 9th Avenue, Seattle, WA 98104, USA.
authors.forename: K M
authors.initials: KM
authors.lastname: Kanal
authors.affiliation: Department of Radiology, University of Washington, Box 359728, 325 9th Avenue, Seattle, WA 98104, USA.
authors.forename: K F
authors.initials: KF
authors.lastname: Linnau
authors.affiliation: Department of Radiology, University of Washington, Box 359728, 325 9th Avenue, Seattle, WA 98104, USA. Electronic address: marting@uw.edu.
authors.forename: M L
authors.initials: ML
authors.lastname: Gunn
mesh_terms: D006801:Humans; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D012149:Restraint, Physical / Q000295:instrumentation*; D014057:Tomography, X-Ray Computed