Optimization of beam parameters and iodine quantification in Dual-Energy Contrast Enhanced Digital Breast Tomosynthesis

Dual-Energy Contrast Enhanced Digital Breast Tomosynthesis (DE CEDBT) is a promising technique for breast cancer detection, which combines the strengths of functional and 3D imaging. In the present study, we first focused on the optimization of the acquisition parameters for the low and high-energy projections, which leads to a trade-off between image quality in the recombined slices and the Average Glandular Dose (AGD) delivered to the patient. Optimized parameters were found and experimentally validated on phantom images. Then, we addressed the problem of iodine quantification in the recombined slices. In DE CEDBT, iodine quantification is limited by the z-resolution, due to the restricted angle acquisition inherent to tomosynthesis. We evaluated the lesion thickness above which determination of iodine volumetric concentration is possible. For lesions below this thickness, estimation of iodine concentration is possible if a priori information or a model on the shape of the lesion is available. Iodine quantification for lesions located near the breast boundary is also challenging, due to scatter border effects and variation of the breast thickness in this region. A scatter correction algorithm based on a deconvolution scheme and a thickness compensation algorithm were applied on the low and high-energy projections. Corrected images showed a more accurate quantification of iodine.