The purpose of this study was to investigate the use of a Gallium Arsenide (GaAs) photon-counting spectral mammography system to differentiate between Type I and Type II calcifications. Type I calcifications, consisting of calcium oxalate dihydrate (CO) or weddellite compounds are more often associated with benign lesions, and Type II calcifications containing hydroxyapatite (HA) are associated with benign or malignant lesions.
The study was carried out on a custom-built laboratory bench-top system using the SANTIS 0804 GaAs detector prototype system from DECTRIS Ltd. Measurements were performed on CIRS (Norfolk, VA) swirl and uniform phantoms mimicking a 50% adipose, 50% fibroglandular breast tissue composition with inserted clusters of synthetic microcalcifications. First, an inverse problem-based approach was used to estimate the full energy x-ray transmission fraction factor using known basis transmission factors of varying thicknesses of Aluminum and PMMA at each pixel. Secon
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