Digital vs Standard Mammogram Density Estimates

Automated estimates of breast density made from synthetic digital mammograms is comparable to those from standard-dose mammograms, according to a study published in Radiology.

Researchers from the University of Pennsylvania in Philadelphia undertook a study to evaluate agreement between automated estimates of breast density made from standard-dose versus synthetic digital mammograms in a large cohort of women undergoing screening.

The study included 3,668 negative (Breast Imaging Reporting and Data System category 1 or 2) digital breast tomosynthesis (DBT) screening examinations consecutively performed over a four-month period. Both standard-dose and synthetic mammograms were available for analysis and were retrospectively analyzed.

The “For Presentation” standard-dose mammograms and synthetic images were analyzed by using a fully automated algorithm. Agreement between density estimates was assessed by using Pearson correlation, linear regression, and Bland-Altman analysis. Differences were evaluated by using the paired Student t test.

The results showed that breast percentage density (PD) estimates from synthetic and standard-dose mammograms were highly correlated (r = 0.92, P < .001), and the 95% Bland-Altman limits of agreement between PD estimates were −6.4% to 9.9%. The synthetic mammograms had PD estimates an average of 1.7% higher than standard-dose mammograms), with a larger disagreement by 1.56% in women with highly dense breast tissue.

The researchers concluded that fully automated estimates of breast density made from synthetic mammograms were generally comparable to those made from standard-dose mammograms. This finding could be important, they wrote. As clinicians strive to reduce radiation doses in screening mammograms, standard two-dimensional mammographic images are increasingly being replaced by synthetic mammograms in DBT screening.