Improving Mammographic Density Estimation in the Breast Periphery

Mammographic density is a strong risk factor for breast cancer. Volumetric breast density can be estimated from a digital mammogram by modelling the imaging process; this provides a more accurate assessment than subjective and 2D area-based methods. However, reliable density estimation in the uncompressed peripheral breast region and determination of compression paddle tilt are still open and challenging problems that affect the accuracy of measurement. Here we present a complete system that is able to perform thickness correction for both the compressed and uncompressed breast regions. The system was evaluated on a dataset of 208 mammograms, and compared with results from commercial software Volpara (TM) (version 1.5). The proposed method yielded Pearson correlation coefficients (PCC) of volumetric breast density (VBD) between left and right breasts of 0.88 (CC view) and 0.91 (MLO view). The PCC between Volpara (TM) VBD and our method is 0.93.