Classification of the micromorphology of breast calcifications in x-ray dark-field mammography

The distant goal of this investigation is to reduce the number of invasive procedures associated with breast micro calcification biopsies, by improving and refining conventional BIRADS micro calcification assessments with x-ray dark-field mammography. The study was institutional review board (IRB) approved. A dedicated grating-based radiography setup (Mo-target, 40 keV, 70 mA) was used to investigate one breast mastectomy and 31 biopsies with dark-field mammography. Comparing the absorption and scattering properties of micro calcifications clusters enables accessing information on the interior morphology on the micron-scale retrieved in a non-invasive manner. Insights underlying the micro morphological nature of breast calcifications were verified by comprehensive high-resolution micro-CT measurements. It was found that Dark-field mammography allows a micro-structural classification of breast micro calcification as ultra-fine, fine, pleomorphic and coarse textured using conventional detectors. Dark-field mammography is thereby highly sensitive to minor structural deviations. Finally, the determined micro-texture of the investigated micro calcifications was correlated with findings obtained from histopathological work up. The presented results demonstrate that dark-field mammography yields the potential to enhance diagnostic validity of current micro calcification analysis - which is yet limited to the exterior appearance of micro calcification clusters - and thereby reduce the number of invasive procedures.