title: Radiation exposure of digital breast tomosynthesis using an antiscatter grid compared with full-field digital mammography.
abstract: OBJECTIVE
  Our study aim was to assess the radiation dose of digital breast tomosynthesis (DBT) in comparison to full-field digital mammography (FFDM) in a clinical setting.
  
  
  METHODS
  Two-hundred four patients were consecutively included, of which 236 complementary DBT and FFDM examinations were available. All acquisitions were performed on a single commercially available mammography system capable of FFDM and DBT acquisitions using an antiscatter grid. The average glandular dose (AGD) was calculated for each examination using the Dance method. For this, tube output and half-value layer were measured, and the required exposure parameters (target/filter material, tube voltage, tube load, compressed breast thickness) were retrieved from the DICOM metadata. The DBT and FFDM AGD values were pairwise tested, and a subanalysis with respect to breast thickness was performed.
  
  
  RESULTS
  The mean (SD) AGD values for a single-view DBT and FFDM were 1.49 (0.36) mGy and 1.62 (0.55) mGy, respectively, which are small but statistically significant differences. This difference may be partially attributed to the small difference in the mean breast thickness between FFDM and DBT (3 mm). In this patient population, the AGD was lower for DBT than for FFDM in 61% of the patients. When patients were categorized according to breast thickness, the AGD of DBT was only significantly smaller than the AGD of FFDM for breast thickness categories larger than 50 mm, indicating that the dose reduction for DBT compared with FFDM was more pronounced in thick breasts.
  
  
  CONCLUSIONS
  The radiation dose of patients undergoing a single-view DBT was comparable to a single-view FFDM. For patients with thicker breasts, the radiation dose of DBT was slightly lower than FFDM.
authors.affiliation: From the *Departments of Radiology and Nuclear Medicine, †GROW, School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht; and ‡Dutch Reference Center for Screening, Nijmegen, the Netherlands.
authors.forename: Leonie E
authors.initials: LE
authors.lastname: Paulis
authors.forename: Marc B I
authors.initials: MB
authors.lastname: Lobbes
authors.forename: Ulrich C
authors.initials: UC
authors.lastname: Lalji
authors.forename: Nicky
authors.initials: N
authors.lastname: Gelissen
authors.forename: Ramona W
authors.initials: RW
authors.lastname: Bouwman
authors.forename: Joachim E
authors.initials: JE
authors.lastname: Wildberger
authors.forename: Cécile R L P N
authors.initials: CR
authors.lastname: Jeukens
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008327:Mammography; D008875:Middle Aged; D011829:Radiation Dosage; D000069079:Radiation Exposure; D011856:Radiographic Image Enhancement; D014057:Tomography, X-Ray Computed