Corneal lenticule allotransplant

1 April 2017 | Magdalena Popiela | EYE - Cornea, EYE - General

This animal study looked at corneal lenticule allograft transplantation in rabbits. Seven rabbits underwent small incision lenticule extraction (SMILE) procedures, where their stromal lenticules were extracted and transplanted fresh into pre-prepared corneal stromal pockets of seven recipient eyes. Animals were observed for six months and underwent slit-lamp examination, pachymetry, in vivo optical coherence tomography (OCT) and in vivo confocal microscopy at each study time point. Histology was performed at six months. Initially corneal oedema was observed at the site of transplanted lenticules. This settled completely by month one leaving clear cornea without visible graft boundaries. Central corneal thickness increased by 59 microns at six months on average. OCT confirmed complete integration of the lenticules within the recipient stromas, with very faint hyper-reflective border visible at month six postoperatively. Confocal microscopy showed nerve fibres regeneration by month one and inactivation of keratocytes by month six. Histology at six months showed disorganised collagen fibres within the transplanted lenticules. There were no postoperative complications or rejection episodes. This study shows promising results for fresh corneal lenticule allograft transplantation, which could be utilised to treat both refractive and structural corneal abnormalities. Further studies are needed to assess optical quality and effect of disorganised lenticule collagen fibres on visual function.