There are several complementary methods able to visualize the internal structures of eyes in clinics. Each clinical intravital imaging method is particularly suited in the diagnosis of pathologies affecting a specific zone of the eye.Despite the significant technological progress, the visualization of the entire eyeball at the micrometric resolution is yet an unsolved task both in clinical diagnostics and in laboratory research. With this respect, high resolutionimages of the eyeball would be extremely useful, even in preclinical research, in the study of different pathologies of the retina, the lens, the optical nerve etc. In this work we combined the state of the art of micro computed tomography technology with phase-contrast imaging , an innovative highly sensitive technique well adapted to investigate soft tissues without the use of contrast agents; we applied the technique in the post-mortem analysis of four Macaca fascicularis eyes and three New Zealand rabbit eyes . The imaging technique applied is the propagation-based imaging technique [4, 5]. The experiments have been carried out at ID17 Biomedical Beamline of the European Synchrotron Radiation Facility. Monochromatic beams of 35 keV for the enucleatedand 70 keV for theintracranial cases have been used. The detection system was composed by a PCO edge 5.5 coupled with a 2X optic and a YAG scintillator screen. This system allows a final isotropic pixel size of ~3.1 µm. A 3D visualization of the entire enucleated and intracranial (rabbit) globe has been obtained for the first time with unprecedented resolution. Rendering of the 3D volume have been obtained as well for both cases. These images show the potential of phase-contrast imaging applied to the vision organ. The success of this pilot study paves the way to ophthalmological microCT studies in-vivo.
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