title: Dose reduction in digital breast tomosynthesis (DBT) screening using synthetically reconstructed projection images: an observer performance study.
abstract: OBJECTIVE
  The aim of this study was to retrospectively compare the interpretive performance of synthetically reconstructed two-dimensional images in combination with digital breast tomosynthesis (DBT) versus full-field digital mammography (FFDM) plus DBT.
  
  
  METHODS
  Ten radiologists trained in reading tomosynthesis examinations interpreted retrospectively, under two modes, 114 mammograms. One mode included the directly acquired full-field digital mammograms combined with DBT, and the other included synthetically reconstructed projection images combined with DBT. The reconstructed images do not require additional radiation exposure. The two modes were compared with respect to sensitivity, namely, recommendation to recall a breast with either a pathology-proven cancer (n = 48) or a high-risk lesion (n = 6), and specificity, namely, no recommendation to recall a breast not depicting an abnormality (n = 144) or depicting only benign abnormalities (n = 30).
  
  
  RESULTS
  The average sensitivity for FFDM with DBT was 0.826, compared to 0.772 for synthetic FFDM with DBT (difference, 0.054; P = .017 and P = .053 for fixed and random reader effects, respectively). The proportions of breasts with no or benign abnormalities recommended to be recalled were virtually the same: 0.298 and 0.297 for the two modalities, respectively (95% confidence intervals for the difference, -0.028 to 0.036 and -0.070 to 0.066 for fixed and random reader effects, respectively). Sixteen additional clusters of microcalcifications ("positive" breasts) were missed by all readers combined when interpreting the mode with synthesized images versus FFDM.
  
  
  CONCLUSIONS
  Lower sensitivity with comparable specificity was observed with the tested version of synthetically generated images compared to FFDM, both combined with DBT. Improved synthesized images with experimentally verified acceptable diagnostic quality will be needed to eliminate double exposure during DBT-based screening.
authors.affiliation: University of Pittsburgh, Department of Radiology, Radiology Imaging Research, Pittsburgh, PA 15213, USA. gurd@upmc.edu
authors.forename: David
authors.initials: D
authors.lastname: Gur
authors.forename: Margarita L
authors.initials: ML
authors.lastname: Zuley
authors.forename: Maria I
authors.initials: MI
authors.lastname: Anello
authors.forename: Grace Y
authors.initials: GY
authors.lastname: Rathfon
authors.forename: Denise M
authors.initials: DM
authors.lastname: Chough
authors.forename: Marie A
authors.initials: MA
authors.lastname: Ganott
authors.forename: Christiane M
authors.initials: CM
authors.lastname: Hakim
authors.forename: Luisa
authors.initials: L
authors.lastname: Wallace
authors.forename: Amy
authors.initials: A
authors.lastname: Lu
authors.forename: Andriy I
authors.initials: AI
authors.lastname: Bandos
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D016014:Linear Models; D008327:Mammography; D008875:Middle Aged; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement / Q000379:methods; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
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