Grating-based X-ray dark-field imaging: a new paradigm in radiography

Grating-based X-ray dark-field contrast is an emerging new imaging modality that is demonstrating particularly high potential for radiography. The signal in dark-field X-ray imaging is determined by small-angle X-ray scattering at structures typically below the spatial resolution of the imaging setup. Thus, this technique not only yields complementary information but also visualizes information that lies under the resolution limit for conventional, absorption-based radiography. Grating-based X-ray dark-field imaging has been shown to be feasible with both synchrotron radiation and conventional X-ray tubes. Lung, breast, and bone imaging have been identified as the applications promising the main impact, but other applications are on the horizon. Specifically, dark-field radiography has been used to detect pulmonary emphysema and assesses its regional distribution in mice and holds promise to improve the visualization of micro-calcifications in mammography and yields information about bone microstructure. Further technical developments are required to make the technique suitable for clinical use.