Proceedings Article | 19 September 2019
Kaye Susannah Morgan, Regine Gradl, Martin Dierolf, Christoph Jud, Benedikt Günther, Freda Werdiger, Mark Gardner, Patricia Cmielewski, Alexandra McCarron, Nigel Farrow, Helena Haas, Melanie Kimm, Lin Yang, David Kutschke, Tobias Stoeger, Otmar Schmid, Klaus Achterhold, Franz Pfeiffer, David Parsons, Martin Donnelley
KEYWORDS: Synchrotrons, X-ray imaging, In vivo imaging, X-ray sources, X-rays, Synchrotron x-ray imaging, Lung, Light sources, Medical imaging, Spatial coherence
Bright synchrotron x-ray sources enable imaging with short exposure times, and hence in a high-speed image sequence. These x-ray movies can capture not only sample structure, but also how the sample changes with time, how it functions. The use of a synchrotron x-ray source also provides high spatial coherence, which facilitates the capture of not only a conventional attenuation-based x-ray image, but also phase-contrast and dark-field signals. These signals are strongest from air/tissue interfaces, which means that they are particularly useful for examining the respiratory system.
We have performed a range of x-ray imaging studies that look at lung function, airway surface function, inhaled and instilled treatment delivery, and treatment effect in live small animal models [Morgan, 2019]. These have utilized a range of optical set-ups and phase-contrast imaging methods in order to be sensitive to the relevant sample features, and be compatible with high-speed imaging. For example, we have used a grating interferometer to measure how the airsacs in the lung inflate during inhalation, via changes in the dark-field signal [Gradl, 2018], a single-exposure, single-grid set-up to capture changes in the liquid lining of the airways [Morgan, 2015] and propagation-based phase contrast to image clearance of inhaled debris [Donnelley, 2019]. Studies have also utilized a range of analysis methods to extract how the sample features change within a time-sequence of two-dimensional projections or three-dimensional volumes.
While these imaging studies began in large-scale synchrotron facilities, we have recently performed these kinds of studies at an inverse-Compton-based compact synchrotron, the Munich Compact Light Source (MuCLS) [Gradl, 2018b].
1. Morgan, Kaye, et al., “Methods for dynamic synchrotron X-ray imaging of live animals.”, under review 01/2019.
2. Gradl, R., et al. "Dynamic in vivo chest x-ray dark-field imaging in mice." IEEE Transactions on Medical Imaging (2018).
3. Morgan, Kaye S., et al. "In vivo X-ray imaging reveals improved airway surface hydration after a therapy designed for cystic fibrosis." American Journal of Respiratory and Critical Care Medicine 190.4 (2014): 469-472.
4. Donnelley, Martin, et al. "Live-pig-airway surface imaging and whole-pig CT at the Australian Synchrotron Imaging and Medical Beamline." Journal of Synchrotron Radiation 26.1 (2019).
5. Gradl, Regine, et al. "In vivo Dynamic Phase-Contrast X-ray Imaging using a Compact Light Source." Scientific Reports 8.1 (2018b): 6788.