We applied quantitative dynamic full-field OCT (qDFFOCT) to imaging of human induced pluripotent stem cell retinal organoids which are a platform for investigating retinal development, pathophysiology, and cellular therapies. In contrast to histological analysis and immunofluorescence staining in which multiple specimens fixed at different times are used to reconstruct developmental processes, qDFFOCT imaging can provide repeated images and analysis of the same living organoids with a contrast created by intracellular organelle motion and linked to metabolism. In order to quantify the dynamic signal, we computed each image in Hue-Saturation-Value color-space and benefitted from the latest advances in GPU computing to accelerate the process. We performed time-lapse acquisitions in a locked plane, highlighting cell differentiation, division and mitosis with a sub-micrometer resolution. By moving deeper into the samples, we were also able to acquire series of planes in depth to reconstruct the organoid 3D organization. We also applied qDFFOCT on a damaged macaque cornea and used cutting edge algorithms to track cell motion and successfully reconstruct a migration map of epithelial wound healing. This could help understand the healing mechanism and have great interest in cell therapy. Besides showing our latest results we will explain the signal processing chain we developed to compute quantitative dynamic images where the colors code continuously for dynamic frequencies. Our overall aim is to use the dynamic signal as a non-invasive marker to predict cell type and cell cycle phases, making qDFFOCT a new label-free imaging method.
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