X-ray phase contrast tomography; Proof of principle for post-mortem imaging

Objective: To demonstrate the feasibility of using X-ray phase-contrast tomography to assess internal organs in a post-mortem piglet model, as a possible non-invasive imaging autopsy technique. Methods: Tomographic images of a new-born piglet were obtained using a free-space propagation X-ray phasecontrast imaging setup at a synchrotron (European Synchrotron Radiation Facility, Grenoble, France). A monochromatic X-ray beam (52 keV) was used in combination with a detector pixel size of 46346mm2. A phase-retrieval algorithm was applied to all projections, which were then reconstructed into tomograms using the filtered-back projection algorithm. Images were assessed for diagnostic quality. Results: Images obtained with the free-space propagation setup presented high soft-tissue contrast and sufficient resolution for resolving organ structure. All of the main body organs (heart, lungs, kidneys, liver and intestines) were easily identified and adequately visualized. In addition, grey/white matter differentiation in the cerebellum while still contained within the skull was shown. Conclusion: The feasibility of using X-ray phase-contrast tomography as a post-mortem imaging technique in an animal model has been demonstrated. Future studies will focus on translating this experiment to a laboratorybased setup. Advances in knowledge: Appropriate image processing and analysis enable the simultaneous visualization of both soft-and hard-tissue structures in X-ray phase-contrast images of a complex, thick sample.