Development of desiccated stromal lenticules and study of their integration in vivo

Abstract

AbstractPurposeSMILE (Small Incision Lenticule Extraction) surgery consists in removing a stromal lenticule of a known refractive power. Usually eliminated, it could be advantageously offered on demand for refractive or therapeutic purposes. The aim is to develop desiccation of SMILE lenticules as a long‐term preservation technique and evaluate their quality in vitro and in vivo.MethodsLenticules were collected after SMILE procedures in patients. Lenticules were desiccated under a specific protocol. Histological and electron microscopic analysis were performed. Six rabbit eyes were grafted with an inlay technique which consisted in inserting a desiccated lenticule inside a stromal pocket. Rabbits were sacrificed at different times between 6 and 24 weeks. Their corneas were analysed with optical coherence tomography (OCT), histology and immunofluorescence.ResultsUnder microscopic analyses of desiccated lenticules, we found a preserved stromal architecture after rehydration. We noticed a decellularization of the lenticules after desiccation (shown by both DAPI and haematoxylin eosin staining). All rabbits’ corneas remained clear after grafting. No rejection occurred without any immunosuppressive treatment. With OCT, we noted the lenticular implantation was regular with no decrease in lenticule thickness. On histological analysis, we found no inflammatory infiltration around lenticules. No nuclear material was visible in histology at week 12 inside lenticules. This absence of recolonization with host cells at week 12 was confirmed with DAPI. Analyses at 4 and 6 months are in progress.ConclusionsIn rabbit corneas, we observed a favourable integration of human desiccated SMILE lenticules at this time. We still must investigate the refractive issue of this lenticular implantation. If we obtain favourable results, we could set up a clinical trial with the use of desiccated SMILE lenticules to treat hyperopia or keratoconus.