Comparison of Two-dimensional Synthesized Mammograms versus Original Digital Mammograms Alone and in Combination with Tomosynthesis Images

Abstract

Purpose:To assess interpretation performance and radiation dose when two-dimensional synthesized mammography (SM) images versus standard full-field digital mammography (FFDM) images are used alone or in combination with digital breast tomosynthesis images. Materials and Methods:A fully crossed, mode-balanced multicase (n = 123), multireader (n = 8), retrospective observer performance study was performed by using deidentified images acquired between 2008 and 2011 with institutional review board approved, HIPAA-compliant protocols, during which each patient signed informed consent. The cohort included 36 cases of biopsy-proven cancer, 35 cases of biopsy-proven benign lesions, and 52 normal or benign cases (Breast Imaging Reporting and Data System [BI-RADS] score of 1 or 2) with negative 1-year follow-up results. Accuracy of sequentially reported probability of malignancy ratings and seven-category forced BI-RADS ratings was evaluated by using areas under the receiver operating characteristic curve (AUCs) in the random-reader analysis. Results:Probability of malignancy-based mean AUCs for SM and FFDM images alone was 0.894 and 0.889, respectively (difference, 20.005; 95% confidence interval [CI]: 20.062, 0.054; P = .85). Mean AUC for SM with tomosynthesis and FFDM with tomosynthesis was 0.916 and 0.939, respectively (difference, 0.023; 95% CI: 20.011, 0.057; P = .19). In terms of the reader-specific AUCs, five readers performed better with SM alone versus FFDM alone, and all eight readers performed better with combined FFDM and tomosynthesis (absolute differences from 0.003 to 0.052). Similar results were obtained by using a nonparametric analysis of forced BI-RADS ratings.

The TOMMY trial: a comparison of TOMosynthesis with digital MammographY in the UK NHS Breast Screening Programme – a multicentre retrospective reading study comparing the diagnostic performance of digital breast tomosynthesis and digital mammography with digital mammography alone

“…l For combined imaging with 2D + DBT to be implemented in screening, the use of synthetic 2D to minimise radiation exposure would be advantageous. The overall non-inferiority of synthetic 2D + DBT to 2D alone, shown in our study and in the publications of Skaane et al 78 and Zuley et al, 143 would justify use of this imaging combination in a RCT in a screening setting. However, before synthetic 2D + DBT could be recommended for screening, further comparative work with synthetic 2D and 2D alone should be undertaken; for example quantifying the effect on sensitivity and specificity for lesions with different radiological appearances, of different pathological types (e.g.…”

Is the false-positive rate in mammography in North America too high?

“…161 However, one study which assessed radiologist reporting of 2D mammograms synthesized from DBT data compared with digital mammograms acquired by conventional means found that the use of either mammogram resulted in similar rates of truepositive and FP reporting. 162 The comparable magnitudes of detection sensitivity and FP reporting among digital mammograms and DBT-synthesized mammograms thus show promise for the employment of DBT-synthesized mammograms as an alternative to the acquisition of a conventional digital mammogram. In this respect, radiation dose can be limited to the contribution by DBT image acquisition only, while diagnostic sensitivity and specificity may be maintained with the employment of the synthesized 2D mammogram as an adjunct to the volumetric set of cross-sectional DBT slices through the breast.…”

Digital Breast Tomosynthesis: State of the Art

“…This constitutes an approximate doubling of the MGD as detailed in a recent review on the radiation dose from DBT (90). One possible manner to limit the radiation dose to the breast is by using synthesized two-dimensional (2D) mammograms (SMs) from DBT (91,92), rather than acquiring an additional mammogram. DBT plus SM (hereafter, DBT-SM) can reduce the MGD by approximately 45% compared with DBT-FFDM (90).…”