Dual-energy mammography: a detector analysis

Dual-energy mammography acquisition scenarios employing single-shot techniques are examined using computer simulation. A figure of merit of the signal-to-noise ratio squared over the glandular dose was chosen for the optimization task due to its exposure independence. Doses were evaluated using Monte Carlo techniques. The effects of kilovoltage, prepatient filtration, front detector thickness, mid-detector filtration thickness and composition were studied. Of the six detector pairs studied (Y2O2S/Gd2O2S, SrFBr/BaFBr, Y2O2S/LaOBr, Y2O2S/CaWO4, Y2O2S/YTaO4, and Y2O2S/LuTaO4), Y2O2S/Gd2O2S and SrFBr/BaFBr were found to be the best combinations. The effects of scatter and signal quantization were also examined. An alternative display technique whereby the tissue-subtracted (i.e., calcium) image is colorized and overlaid onto the conventional mammogram is introduced.