title: Evaluation of a new system for chest tomosynthesis: aspects of image quality of different protocols determined using an anthropomorphic phantom.
abstract: OBJECTIVE
  To compare the image quality obtained with the different protocols in a new chest digital tomosynthesis (DTS) system.
  
  
  METHODS
  A chest phantom was imaged with chest X-ray equipment with DTS. 10 protocols were used, and for each protocol, nine acquisitions were performed. Four observers visually rated the quality of the reconstructed section images according to pre-defined quality criteria in four different classes. The data were analysed with visual grading characteristics (VGC) analysis, using the vendor-recommended protocol [12-s acquisition time, source-to-image distance (SID) 180 cm] as reference, and the area under the VGC curve (AUCVGC) was determined for each protocol and class of criteria.
  
  
  RESULTS
  Protocols with a smaller swing angle resulted in a lower image quality for the classes of criteria "disturbance" and "homogeneity in nodule" but a higher image quality for the class "structure". The class "demarcation" showed little dependency on the swing angle. All protocols but one (6.3 s, SID 130 cm) obtained an AUCVGC significantly <0.5 (indicating lower quality than reference) for at least one class of criteria.
  
  
  CONCLUSIONS
  The study indicates that the DTS protocol with 6.3 s yields image quality similar to that obtained with the vendor-recommended protocol (12 s) but with the clinically important advantage for patients with respiratory impairment of a shorter acquisition time.
  
  
  CONCLUSIONS
  The study demonstrates that the image quality may be strongly affected by the choice of protocol and that the vendor-recommended protocol may not be optimal.
authors.affiliation: 1 Departments of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Jadidi
authors.affiliation: 2 Radiology Department, Uppsala University Hospital, Uppsala, Sweden.|3 Radiology, Oncology and Radiation Science, Uppsala University, Uppsala, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Sundin
authors.affiliation: 4 Departments of Clinical Science, Intervention and Technology, Karolinska University Hospital, Stockholm, Sweden.|5 Radiology Department, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Aspelin
authors.affiliation: 6 Department of Radiation Physics, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|7 Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Båth
authors.affiliation: 8 Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.|9 Radiology Department, Karolinska Institute, Stockholm, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Nyrén
mesh_terms: D006801:Humans; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods / Q000592:standards*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods / Q000592:standards*; D013902:Radiography, Thoracic / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D015203:Reproducibility of Results