Digital breast tomosynthesis (DBT) is a three-dimensional X-ray imaging modality that has the potential to decrease the
superimposition effect of breast structural noise, thereby increasing lesion conspicuity. To further improve breast cancer
detection, our work has been devoted to develop a prototype for contrast-enhanced dual-energy tomosynthesis
(CEDET). CEDET involves the injection of an iodinated contrast agent and measures the relative increase in uptake of
contrast in the suspected breast cancer lesion. Either temporal or dual-energy subtraction techniques may be used to
implement CEDET. Both 2D contrast-enhanced dual-energy mammography and 3D tomosynthesis can be applied.
Here we present the design of a prototype CEDET system based on the Siemens MAMMOMAT Inspiration and
employing two additional high-energy filters in addition to the standard Rh filter, the latter being used for the low-energy
acquisitions. A quality factor of squared
signal-difference-to-noise-ratio of iodine per pixel area and average glandular
dose as a function of breast thickness is used to optimize the filter material, the filter thickness, and the tube voltage. The
average glandular dose can be calculated from the entrance surface air kerma using computed conversion coefficients
DgN for the used X-ray spectra. We also present the results of DQE measurements of the amorphous selenium detector
involved. Finally, results of phantom tests for tomosynthesis acquisition and first clinical data in the 2D mode will be
shown.
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