title: The use of model-based iterative reconstruction to decrease ED radiation exposure.
abstract: BACKGROUND
  The radiation risk posed by diagnostic computed tomography (CT) is a growing concern. The use of model-based iterative reconstruction (MBIR) technology reduces radiation exposure but requires additional processing time. The goal of this study was to compare MBIR and a standard CT reconstructive protocols in terms of emergency department (ED) visit duration and reduction in radiation exposure.
  
  
  METHODS
  A retrospective, matched, case-control design was used to compare patients who received MBIR and standard protocol abdomen and pelvis CTs. ED length of stay (LOS) and radiation exposure were the 2 primary outcome variables.
  
  
  RESULTS
  During the study period, 121 patients met inclusion criteria and were matched to controls for a total of 242 subjects. Although the low-dose group LOS was slightly longer, there was no significant difference in LOS. Mean differences were 18 minutes overall (520 vs 502 minutes; P = .497), 11 minutes for admitted patients (587 vs 576 minutes; P = .839), and 22 minutes for discharged patients (490 vs 468 minutes; P = .482). The mean volume CT dose index for the standard-dose CT was 11.6 ± 8.3 and 7.7 ± 4.6 mGy for the reduced-dose CT, a 34% decrease (P < .001).
  
  
  CONCLUSIONS
  Use of MBIR in the ED may provide decreased radiation exposure while minimally impacting ED LOS.
authors: Division of Emergency Medicine, University of Washington School of Medicine, Seattle, WA, USA.
authors: Medley O
authors: MO
authors: Gatewood
authors: Department of Emergency Medicine, Madigan Army Medical Center Emergency Medicine Residency, Tacoma, WA, USA.
authors: Lindsay
authors: L
authors: Grubish
authors: Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA.
authors: Janet M
authors: JM
authors: Busey
authors: Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA.
authors: William P
authors: WP
authors: Shuman
authors: Division of Emergency Medicine, University of Washington School of Medicine, Seattle, WA, USA. Electronic address: strote@uw.edu.
authors: Jared
authors: J
authors: Strote
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D011835:Radiation Protection / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011860:Radiography, Abdominal; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*