title: A new low-dose multi-phase trauma CT protocol and its impact on diagnostic assessment and radiation dose in multi-trauma patients.
abstract: OBJECTIVE
  Computed tomography (CT) examinations, often using high-radiation dosages, are increasingly used in the acute management of polytrauma patients. This study compares a low-dose polytrauma multi-phase whole-body CT (WBCT) protocol on a latest generation of 16-cm detector 258-slice multi-detector CT (MDCT) scanner with advanced dose reduction techniques to a single-phase polytrauma WBCT protocol on a 64-slice MDCT scanner.
  
  
  METHODS
  Between March and September 2015, 109 polytrauma patients (group A) underwent acute WBCT with a low-dose multi-phase WBCT protocol on a 258-slice MDCT whereas 110 polytrauma patients (group B) underwent single-phase trauma CT on a 64-slice MDCT. The diagnostic accuracy to trauma-related injuries, radiation dose, quantitative and semiquantitative image quality parameters, subjective image quality scorings, and workflow time parameters were compared.
  
  
  RESULTS
  In group A, statistically significantly more arterial injuries (p = 0.04) and arterial dissections (p = 0.002) were detected. In group A, the mean (±SD) dose length product value was 1681 ± 183 mGy*cm and markedly lower when compared to group B (p < 0.001). The SDs of the mean Houndsfield unit values of the brain, liver, and abdominal aorta were lower in group A (p < 0.001). Mean signal-to-noise ratios (SNRs) for the brain, liver, and abdominal aorta were significantly higher in group A (p < 0.001). Group A had significantly higher image quality scores for all analyzed anatomical locations (p < 0.02). However, the mean time from patient registration until completion of examination was significantly longer for group A (p < 0.001).
  
  
  CONCLUSIONS
  The low-dose multi-phase CT protocol improves diagnostic accuracy and image quality at markedly reduced radiation. However, due to technical complexities and surplus electronic data provided by the newer low-dose technique, examination time increases, which reduces workflow in acute emergency situations.
authors.affiliation: Functional Unit for Musculoskeletal Radiology, Function Imaging and Physiology, Karolinska University Hospital, Karolinska Vägen Solna, SE-17176, Stockholm, Sweden.
authors.forename: Zlatan
authors.initials: Z
authors.lastname: Alagic
authors.affiliation: Functional Unit for Musculoskeletal Radiology, Function Imaging and Physiology, Karolinska University Hospital, Karolinska Vägen Solna, SE-17176, Stockholm, Sweden.
authors.forename: Andreas
authors.initials: A
authors.lastname: Eriksson
authors.affiliation: General Electrics Healthcare Sverige AB, Danderyd, Sweden.
authors.forename: Erika
authors.initials: E
authors.lastname: Drageryd
authors.affiliation: Functional Unit for Musculoskeletal Radiology, Function Imaging and Physiology, Karolinska University Hospital, Karolinska Vägen Solna, SE-17176, Stockholm, Sweden.
authors.forename: Sara Rezaei
authors.initials: SR
authors.lastname: Motamed
authors.affiliation: Functional Unit for Musculoskeletal Radiology, Function Imaging and Physiology, Karolinska University Hospital, Karolinska Vägen Solna, SE-17176, Stockholm, Sweden. marius.wick@sll.se.|Diagnostic Radiology, Institute for Molecular Medicine and Surgery (MMK), Karolinska Institutet, Stockholm, Sweden. marius.wick@sll.se.
authors.forename: Marius C
authors.initials: MC
authors.lastname: Wick
mesh_terms: D000328:Adult; D003287:Contrast Media; D005260:Female; D006801:Humans; D007472:Iohexol; D008297:Male; D009104:Multiple Trauma / Q000000981:diagnostic imaging*; D011829:Radiation Dosage; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*; D051598:Whole Body Imaging / Q000295:instrumentation / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol
keywords: ASIR-V; CT protocol; Missed injuries; Radiation dose; Trauma CT; Whole-body CT angiography