It has been proposed that the sensitivity of breast lesion detection can be improved with phase-contrast mammographic
imaging. The recently introduced clinical system by Konica-Minolta, for example, reportedly yields enhanced lesion
detectability. We hypothesize that the use of an optimized x-ray spectrum will result in even better performance. To test
this hypothesis, we have performed a study of several clinical spectra from Mo and W sources over a broad spectral
range. In the study, we have incorporated established dose measurements from a simple breast phantom used in the
digital mammography literature, which has been updated to incorporate breast density properties in addition to
conventional attenuation information. Established phase-contrast imaging simulation techniques, which employed a
Fresnel propagator, were used to generate edge-enhanced radiographs for analysis. In addition, detector sensitivity and
tube loading parameters were incorporated into the analysis. The resulting mammography images were analyzed via
measurement of object edge-enhanced contrast.
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